Measurement of Radon concentration in water, soil and air...
Transcript of Measurement of Radon concentration in water, soil and air...
i
Measurement of Radon concentration in water,
soil and air in and around earthquake hit areas
in N.W.F.P
By
Fayaz Khan
CIIT/SP04-PPH-002/ISB
Ph.D Thesis
Department of Physics
COMSATS Institute of Information Technology
Islamabad- Pakistan
Spring, 2011
ii
COMSATS Institute of Information Technology
Measurement of Radon concentration in water,
soil and air in and around earthquake hit areas
in N.W.F.P
A Thesis Presented to
COMSATS Institute of Information Technology, Islamabad
In partial fulfillment
of the requirement for the degree of
Ph.D
Physics
By
Fayaz Khan
CIIT/SP04-PPH-002/ISB
Spring, 2011
iii
Measurement of Radon concentration in water,
soil and air in and around earthquake hit areas
in N.W.F.P
Thesis submitted to the Department of Physics in partial fulfillment of the
requirements for the award of Degree of Ph.D.
Name Registration Number
Fayaz Khan CIIT/SP04-PPH-002/ISB
Supervisor
Prof. Dr. Ehsan Ullah Khan, TI
Department of Physics,
Spring, 2011
iv
Final Approval
This thesis titled
Measurement of Radon concentration in water,
soil and air in and around earthquake hit areas
in N.W.F.P
By
Fayaz Khan
CIIT/SP04-PPH-002/ISB has been approved
For the COMSATS Institute of Information Technology, Islamabad
External Examiner: 1.----------------------------------------------------------------------------
Dr. Gul Feroz Tariq (KRL), H.No.496-F, Ibne-Sina Road, G-9/3, Islamabad
External Examiner: 2.-----------------------------------------------------------------------------
Dr. Nasir Majeed Mirza, Chief Scientist PIEAS, Nilore, Islamabad
Supervisor: -----------------------------------------------------------------------------------------
Prof. Dr. Ehsan Ullah Khan, Department of Physics
HOD: -----------------------------------------------------------------------------------------------
Prof. Dr. Mahnaz Qadir Haseeb, Department of Physics CIIT, Islamabad
Dean, Faculty of Science ------------------------------------------------------------------------
Prof. Dr. Arshad Saleem Bhatti
v
Declaration
I Fayaz Khan (CIIT/SP04-PPH-002/ISB) hereby declare that I have under taken the
research work presented in this thesis, during the scheduled period of study. I also
declare that I have not copied any material from any source except referred to
wherever due. If any violation of Higher Education Commission (HEC) rules in my
research is found, I shall be legally responsible for punishment under the plagiarism
rules of the HEC.
Date: _________________ Signature of the student:
____________________
(Fayaz Khan)
(CIIT/SP04-PPH-002/ISB)
vi
Certificate
It is certified that Mr. Fayaz Khan (CIIT/SP04-PPH-002/ISB) PhD student in
Experimental Radiation Physics at the Department of Physics, COMSATS Institute of
Information Technology (CIIT), Islamabad has carried out all the research related to
his thesis under my supervision. He has completed his experimental work in the
Radiation Physics Laboratory, Department of Physics, COMSATS Institute of
Information Technology (CIIT), Islamabad.
Supervisor:
Prof. Dr. Ehsan Ullah Khan, TI,
Department of Physics
Submitted through:
Prof. Dr. Mahnaz Qadir Haseeb
Head, Department of Physics
CIIT, Islamabad
vii
DEDICATED
To my parents, wife, daughters (Gull, Mah, Arsh and
Hayya) and son (Ahmad)
viii
ACKNOWLEDGEMENTS First of all I thank the Almighty ALLAH, the most Merciful, and the most Beneficent,
Who blessed me with sound health and chance to complete this research work
successfully.
I pay my thanks to my Supervisors Prof. Dr. Ehsan Ullah Khan (TI),
Department of Physics and Prof. Dr. Iftihar Ahmed Raja, Department of
Environmental Sciences, COMSATS Institute of Information Technology (CIIT),
Abbottabad, for their kind direction, leadership and assistance during this research
work. I whole-heartedly express my admiration to Prof. Dr. Nimatullah Khattak,
National Center of Excellence in Geology, University of Peshawar Without his
careful consideration and encouragement, this project could have never been
completed. I am also highly obliged to Dr. Nawab Ali, Senior Scientific Officer,
PINSTECH, Islamabad, whose help in this research work is more significant than
anyone else. I also commend the cooperation and support extended to me by Prof. Dr.
Arshad Saleem Bhatti, Dean faculty of science and Prof. Dr. Sajid Qamar, Chairman
Physics Department, CIIT. I am grateful to Prof. Dr. Mahnaz Qadir Haseeb, Head of
the Department of Physics, for creating a lively scientific environment. I am really
thankful to Dr. Hameed Ahmed Khan, (SI) and Dr. Abdul Waheed (PoP), Advisors,
Radiation Physics Laboratory who always guided me with kind advice and extended
his full support in completion of my work. I am really thankful for the valuable co-
operation of Dr. Ishaq Ahmad. I desire to record my gratitude to Dr. S. M. Junaid
Zaidi(SI), Rector of COMSATS Institute of Information Technology (CIIT) and Prof.
Dr. Raheel Qamar (TI) Dean Research and Innovation COMSATS Institute of
Information Technology (CIIT) for their facilitation of a very high-quality research
atmosphere and facilities in the newly recognized institute; and deliver my
thankfulness to all the faculty members of the Department of Physics, for creating a
dynamic scientific environment.
Astounding credit to the HEC, Government of Pakistan, for bestowing upon
me the scholarship under Indigenous 5000 Scheme.
I am thankful from the core of my heart to all my colleagues in the
Department of Physics, CIIT, Islamabad, for their moral and physical help throughout
this research work. I would cordially pay special thanks to Dr. Zafar Wazir for
assisting me in order to complete the research work. I cannot ignore the help of
ix
Mukhtar Ahmed Rana and other members of the PINSTECH and pay special thanks
to all these beacons.
I would also like to pay honor to all my teachers for their continuous
encouragement and support during my education career. I am also thankful to my
parent institution (Pakistan International Public School & College) and I really admire
the full support and kind cooperation of the institute, Managing Director Brig(R) Ejaz
Akbar, Principal Brig(R) Muhammad Ehsan and Vice Principal Kanwer Tayyab Ali.
Last but not the least; I am extremely grateful to my loving parents,
respectable brothers, sisters and other family members who always pray for my
success in every walk of life. I am deeply thankful to my caring wife and lovely
children for their love and support throughout my Ph.D term.
Fayaz Khan
(CIIT/SP04-PPH-002/ISB)
x
ABSTRACT
In this work measurements of radon concentration in water, soil and air in and around
earthquake hit areas in N.W.F.P, Pakistan( new name is now Khyber Pakhtun-Khwa
Province) were carried out keeping in view that there may be more radon
concentrations because the area was hit by an earthquake of ML= 7.6 on October 8,
2005. High radon levels in soil and water may have contributed to the indoor radon
concentration, subsequently a threat to the health of the people.
The centre of the October 8, 2005 devastating earthquake was the northwest-
striking Balakot–Bagh (B–B) fault, which had been mapped by the Geological Survey
of Pakistan prior to the earthquake but had not been recognized as an active fault
except for a 16 km section near Muzaffarabad.
The area had not been surveyed previously for radon concentrations. The area
has geological importance as well; because some of it lies on the active Balakot-Bagh
fault line while other is located in its surroundings. This survey was conducted in
three different media; water (from drinking sources), soil (sub-surface radon gas) and
air (in the dwellings).
The survey was carried out in the five districts of Hazara Division in general
and in Balakot area in particular, being located at or around the Balakot-Bagh active
fault, using two techniques: (i) the passive technique is based on tracks formation in
39CR (trade name of diethylene glycol bis allyl carbonate) alpha track recorder
used in the NRPB dosimeter with a known calibration and (ii) the active technique is
based on the α activity measurements through spectral analysis in the instant air
samples collected through the 7RAD instrument of Durridge company. This technique
is useful for getting average radon concentrations from the data integrated over certain
time period. Doses were calculated from the indoor air and groundwater radon
concentrations and the results obtained were then interpreted.
The water samples were from drinking sources of the area near the fault line of
Balakot especially and in the surroundings generally. The drinking sources include
surface, spring and bore-hole water. Near the fault line at Balakot, the drinking source
is the spring water so the spring water results of this area were compared with the
spring water of the other parts of the study area. However, the sources of drinking
water such as surface and bore-hole water in the Balakot area were also surveyed.
xi
Radon concentration in the spring water near the B-B fault line were compared with
the radon concentrations in the spring water in other part of study area away from the
fault zone.
Soil gas radon concentration in an area can be used not only to know about the
radon related health hazards but also can be used as a useful tracer for locating active
geological faults and for predicting any forthcoming earthquake within an area. The
soil gas radon concentrations near the B-B fault line and other parts of study areas
were measured. The results of B-B fault line were analyzed and compared with the
other parts of the study area.
Indoor radon survey was carried out in dwellings during four seasons of the
year for one year and also on year basis to study the seasonal variation and to
calculate the seasonal correction factor, respectively. The indoor radon concentrations
were measured in the houses near the fault line and the surroundings. The results for
the two regions were then compared. Indoor radon concentration levels of different
seasons were compared with each other and with those taken on yearly basis.
Comparison of radon levels in the indoor air of the houses made up of different
materials and among the radon levels of the same houses on different stories were
made.
The groundwater radon concentration is higher in some part of the area than
the US EPA recommended maximum contamination limit ( MCL ) of 11.0 3mkBq
nevertheless within the range of limit adopted by European countries.
Soil gas radon concentrations were found higher near the B-B fault line with
an average value of 11.9 3mkBq as compared to other sites of the study area. The
mean value of soil gas radon concentrations in the whole study area was found as 7.6
3mkBq .
The indoor radon concentrations were found to be higher than the world
average of 48 3mBq but most of the values are below the Environmental Protection
Agency’s US EPA recommended value of 148 3mBq and the annual doses which
the people of the area receive are within the safe limits of 3-10 mSv set by
International Council of Radiological Protection 65ICRP .
The indoor, soil gas and ground water radon concentrations were found to be
higher near the fault line as compared to the areas away from the fault zone.
xii
TABLE OF CONTENTS
List of figures…………………………………………………………………xvi
List of tables………………………………………………………………...xviii
List of abbreviations………………………………………………………......xx
List of publications…………………………………………………………..xxii
Chapter one Introduction 1
1.1 Introduction.…………………………………………………………….1
1.2 Objective………………………………………………………………...2
1.3 Thesis organization……………………………………………………...3
Chapter two Background and literatures review 4
2.1 Radon daughters…………………...……………………………………4
2.2 Radon and risk….……………………………………………………….5
2.2.1 The life cancer estimate……………………...…………………..6
2.2.2 Excess of Lung Cancer Risk……………………………………..7
2.2.3 Radon in water…………………………………………………...8
2.2.4 Health risks due to waterborne radon...……………………….....9
2.3 Soil gas radon………………………………………………………….10
2.4 Indoor radon sources………………………………………………......11
2.5 Literature review……………………………………………………….12
2.5.1 Radon concentration in water………..…………………………12
2.5.2 Soil gas radon concentrations………………………..…………14
2.5.3 Indoor radon concentrations……………………..……………..16
Chapter Three Geology and demography of the study area 21
3.1 Landform of Hazara division…………………………………………..22
3.2 Abbottabad……………………………………………………………..23
3.2.1 Physical feature and topography……………………………...23
3.2.2 Geology……………………………………………………….23
xiii
3.2.3 Climate………………………………………………………..24
3.2.4 Population…………………………………………………….24
3.2.5 Construction materials of the houses…………………………24
3.3 Mansehra………………………………………………………………25
3.3.1 Physical feature and topography……………………………...25
3.3.2 Geology……………………………………………………….25
3.3.3 Climate………………………………………………………..28
3.3.4 Population. ……………………………………………………28
3.3.5 Construction materials of the houses. ………………………...28
3.4 Haripur. ……………………………………………………………......29
3.4.1 Physical feature and topography. …………………………….29
3.4.2 Geology. ……………………………………………………...29
3.4.3 Climate. ………………………………………………………30
3.4.4 Population. ……………………………………………………30
3.4.5 Construction materials of the houses. ………………………...30
3.5 Battgram. ……………………………………………………………...31
3.5.1 Physical feature and topography. …………………………….31
3.5.2 Geology. ……………………………………………………...32
3.5.3 Climate. ………………………………………………………32
3.5.4 Population. ……………………………………………………32
3.5.5 Construction materials of the houses. ………………………...32
3.6 Kohistan. ……………………………………………………………....33
3.6.1 Physical feature and topography. …………………………….33
3.6.2 Geology. ……………………………………………………...33
3.6.3 Climate. ………………………………………………………34
3.6.4 Population. ……………………………………………………34
3.6.5 Construction materials of the houses. ………………………...34
Chapter Four Measurement techniques 36
4.1 Passive techniques. ……………………………………………………37
4.1.1 Charcoal canister technique. …………………………………...38
4.1.2 Electrics. ……………………………………………………….38
xiv
4.1.3 Thermoluminiscent technique. ………………………………...38
4.1.4 Etched tracks detectors. ………………………………………..39
4.1.4.1 Membrane permeation samplers. …………………...39
4.1.4.2 Plastic bag permeation samplers. …………………...39
4.1.4.3 NRPB radon dosimeter. …………………………….40
4.2 Active techniques. …………………………………………………….40
4.2.1 Lucas cell (scintillation method). ……………………………...41
4.2.2 Ionization chamber. ……………………………………………41
4.2.3 Surface barrier detector (SBD). ………………………………..41
4.2.4 Two filter method. ……………………………………………..41
4.2.5 Working level method. ………………………………………...42
Chapter five Experimental 46
5.1 Radon level in water. ………………………………………………….46
5.1.1 Sampling. ………………………………………………………46
5.2 Soil gas radon………………………………………………………….52
5.2.1 Sampling………………………………………………………..52
5.3 Indoor radon concentrations…………………………………………...53
5.3.1 Sampling………………………………………………………..54
Chapter six Results and discussions 57
6.1 Radon concentration in water sources. ………………………………..57
6.1.1 Dose calculation from radon concentrations in water………….68
6.2 Soil gas radon concentrations………………………………………….70
6.3 Results of the indoor radon concentrations……………………………71
6.3.1 Seasonal correction factor……………………………………...73
6.3.2 Comparative study of yearly measured indoor radon and seasonal
averaged indoor radon………………………………………...73
6.3.3 Variation of indoor radon concentrations in different stories and
construction materials…………………………………………74
6.3.4 Dose estimation from indoor radon concentration……………75
xv
6.3.5 The excess of lung cancer in the study area………………….75
Chapter seven Conclusions and future recommendations 91
7.1 Conclusions. …………………………………………………………..91
7.2 Future recommendations………………………………………………94
7.3 References. ……………………………………………………………95
xvi
LIST OF FIGURES
Figure 1.1: Diagram showing the Radon decay chain ………………………………...2
Figure 2.1: Excess lung cancer risk as a function of indoor radon level…………..8
Figure 3.1: Map of N.W.F.P with black shaded portion of Hazara Division (study area)…………………………………………………………………..21
Figure 3.2: Map of the study area………………………………………………...22
Figure 3.3: The Balakot–Bagh (B-B) fault in the Hazara–Kashmir Syntaxis……27
Figure 3.4: Mapping of the study area near Balakot-Bagh fault line……………..26
Figure 4.1: The charcoal canister………………………………………………….43
Figure 4.2: Radon monitoring devices based on etched track detectors (a) filter
permeation sampler (b) plastic bag permeation sampler (c) NRPB
radon dosimeter………………………………………………………44
Figure 4.3: Diagram illustration of the key procedure involved in radon recognition
and assessment by means of an etched trail radon dosimeter………...44
Figure 4.4: Schematic of 7RAD ………………………………………………….45
Figure 4.5: A true picture of 7RAD ……………………………………………...45
Figure 6.1: Frequency allocation of radon concentration in the spring water in
Balakot………………………………………………………….…….80
Figure 6.2: Frequency allocation of radon concentration in the spring water (except
Mansehra) in the study area…………………………………………..81
Figure 6.3: Frequency allocation of radon concentration in the surface water in the
study area……………………………………………………………..81
Figure 6.4: Frequency allocation of radon concentration in the bore water in the
study area……………………………………………………………..82
Figure 6.5: Frequency allocation of radon concentration in all sources of water in
the study area…………………………………………………………82
Figure 6.6: Mean radon concentration ( 3mkBq ) in all sources of drinking water
(except the spring water from Mansehra) in the study area………......83
Figure 6.7: Variation of radon concentration in spring water, along Balakot-Bagh
(B-B) fault line in the Balakot-section………………………………..83
Figure 6.8: Mean annual dose estimated from all sources of drinking water (except
spring water from Mansehra) in the study area………………………84
Figure 6.9: Frequency allocation of soil gas radon in the study area………….....84
xvii
Figure 6.10: Frequency allocation of soil gas radon in Balakot…………………...85
Figure 6.11: Mean soil gas radon concentration ( 3mkBq ) in the study area……..85
Figure 6.12: Variation of soil gas radon concentration, along Balakot-Bagh (B-B)
fault line, in the Balakot-section……………………………………...86
Figure 6.13: Frequency allocation of indoor radon concentration in Balakot…......86
Figure 6.14: Frequency allocation of annual indoor radon concentration in the study
area……………………………………………………………………87
Figure 6.15: Annual mean indoor radon concentrations in the study area………...87
Figure 6.16: Mean indoor radon concentration( 3mBq ) in different seasons of the
year…………………………………………………………………...88
Figure 6.17: Mean indoor radon concentration ( 3mBq ) at ground and first floors in
three district of the study area………………………………………...88
Figure 6.18: Mean indoor radon concentration ( 3mBq ) in different types of
material made houses in the study area………………………………89
Figure 6.19: Seasonal correction factors for the study area………………………..89
Figure 6.20: Comparison of yearly averaged measured indoor radon levels and
seasonal average indoor radon levels in the study area………………90
Figure 6.21: Annual mean dose from indoor radon concentration in the study
area……………………………………………………………………90
xviii
LIST OF TABLES
Table 2.1: Radon concentration in water in different parts of the world………...14
Table 3.1: Construction materials used in the outer walls (%) of the Abbottabad
district………………………………………………………………...25
Table 3.2: Construction materials used in roofs (%) of the Abbottabad district...25
Table 3.3: Construction materials used in the outer walls (%) of the Mansehra
district………………………………………………………………...29
Table 3.4: Construction materials used in roofs (%) of the Mansehra district…..29
Table 3.5: Construction materials used in the outer walls (%) of the Haripur
district………………………………………………………………...31
Table 3.6: Construction materials used in roofs (%) of the Haripur district…….31
Table 3.7: Construction materials used in the outer walls (%) of the Battgram
district. ……………………………………………………………….33
Table 3.8: Construction materials used in roofs (%) of the Battgram district…...33
Table 3.9: Construction materials used in the outer walls (%) of the Kohistan
district. ……………………………………………………………….35
Table 3.10: Construction materials used in roofs (%) of the Kohistan district…...35
Table 3.11: Estimated statistics of Hazara division in 2010………………………35
Table 6.1: Statistical analysis of spring water sampling data from the selected springs in
whole study area. ……………………………………………………...61
Table 6.2: Statistical analysis of surface water sampling data from the selected surface
water in whole study area. ……………………………………………...62
Table 6.3: Statistical analysis of bore-hole water sampling data from the selected wells
in whole study area……………………………………………………..63
Table 6.4: Statistical analysis of all types of drinking sources sampling data from the
selected springs, surface and wells in whole study area…………………...64
Table 6.5: Radon concentrations in the spring water in ( 3mkBq )……………...66
Table 6.6: The radon concentration ( 3mkBq ) in surface and borehole water in
three districts, Abbottabad, Mansehra, and Haripur………………...66
Table 6.7: The radon concentration ( 3mkBq ) in surface and borehole water in
two districts, Battgram and Kohistan and Balakot…………………...67
xix
Table 6.8: The comparison of radon concentration ( 3mkBq ) in deep well water
with previous measurements from different countries……………….68
Table 6.9: Arithmetic mean (A.M), maximum and minimum radon concentration
and annual mean dose estimation from radon in all three sources of
drinking water in the study area………………………………………69
Table 6.10: Radon concentration ( 3mkBq ) in soil gas in Balakot (near fault line)
and other part of the study area……………………………………….71
Table 6.11: Weighted Indoor Radon concentrations ( 3mBq ) in the study area in
the spring season……………………………………………………...76
Table 6.12: Weighted Indoor Radon concentrations ( 3mBq ) in the study area in
the summer season……………………………………………………76
Table 6.13: Weighted Indoor Radon concentrations ( 3mBq ) in the study area in
the autumn season…………………………………………………….77
Table 6.14: Weighted Indoor Radon concentrations ( 3mBq ) in the study area in
the winter season……………………………………………………...77
Table 6.15: Statistics for weighted seasonal indoor radon concentrations ( 3mBq )
in the study area………………………………………………………78
Table 6.16: Weighted yearly indoor radon concentrations ( 3mBq ) in the study
area……………………………………………………………………78
Table 6.17: Arithmetic mean, maximum and minimum weighted indoor radon
concentration for different floors for three districts of the study area
weighted indoor radon………………………………………………..79
Table 6.18: Indoor radon concentration ( 3mBq ) in different types of material
houses………………………………………………………………...79
Table 6.19: Mean annual dose ( mSv ) from the weighted indoor radon
concentration in the study area……………………………………….79
Table 6.20 Excess of lung cancer per million per year (MPY) from the indoor
radon level according to various agencies, in the study area…………80
xx
LIST OF ABBREVIATIONS
N.W.F.P.(KPK) North West Frontier Province (Khyber Pakhtun Khwa)
UNSCEAR United Nations Scientific Committee on the Effects of Atomic
Radiation
EPA Environmental Protection Agency
NCRP National Council for Radiological Protection
WLM Working Level Month
MPY Million Per Year
MCL Maximum Contamination Level
USA United State of America
SSNTD Solid State Nuclear Track Detector
ASPF Alpha Sensitive Plastic Film
CR Columbia Resin
KDC Karlsruhe Diffusion Chamber
FATA Federally Administered Tribal Areas
FJWU Fatima Jinnah Women University
UK United Kingdom
TLD Thermo Luminiscent Detector
NRPB National Radiological Protection Board
HPA Health Protection Agency
PMT Photomultiplier Tube
SBD Surface Barrier Detector
GS Gamma Spectroscopy
LC Lucas Cell
LS Liquid Scintillation
RCC Reinforce Cement Concrete
RCB Reinforce Cement Bricks
B.B Balakot-Bagh
MMT Main Mantle Thrust
WARn Weighted average Radon
DCF Dose Conversion Factor
CPM Counts Per Minute
xxi
DPM Decay Per Minute
AM Arithmetic Mean
SD Standard Deviation
H.No House number
xxii
LIST OF PUBLICATIONS
1. F. Khan, N. Ali, E.U. Khan, N.U. Khattak, K. Khan. Radon Monitoring in water
sources of Balakot and Mansehra cities lying on a Geological Fault line. Radiation
Protection Dosimetry 138 (2), 174-179 (2010).
2. N. Ali, E.U. Khan, F. Khan, P. Akhter, A. Waheed. Determination of aerosol mean
residence time using 210Pb and 7Be radionuclides in the atmosphere of Islamabad.
The Nucleus 47 (1), 25-29 (2010).
3. N. Ali, E.U. Khan, A. Waheed, S. Karim, F. Khan, A. Majeed. Varying track etch
rates along the fission fragments’ trajectories in CR-39 detectors. Chinese Physics
Letters 27 (5), 052903 (2010).
4. N. Ali, E.U. Khan, P. Akhter, F. Khan, A. Waheed. Estimation of mean annual
effective dose through radon concentration in the water and indoor air of
Islamabad and Murree. Radiation Protection Dosimetry 141 (2), 183-191 (2010).
5. F. Khan, N. Ali, E. U. Khan, N. U. Khattak, I. A. Raja, M. U. Rajput, M. A
Baloch. Study of indoor radon concentrations and associated health risks in the
five districts of Hazara division, Pakistan. J. Environ. Monit., 14, 3015-3023
(2012).
6. N. Ali, E.U. Khan, P. Akhter, N.U. Khattak, F. Khan, M. A. Rana. The effect of
air mass origin on the ambient concentrations of 7Be and 210Pb in Islamabad,
Pakistan. Journal of Environmental Radioactivity 102, 35-42 (2011).
Doi:10.1016/j.jenvrad.2010.08.010.
7. F. Khan, I. A. Raja, E. U. Khan, N. Ali. Variation of indoor radon concentrations
at different stories in three districts of Hazara division- Pakistan. Accepted for
presentation at 5th International Conference “Environmentally Sustainable
Development”, ESDev-2013, to be held on August 25-27-2013, at Abbottabad
(submission No: BE-05).
8. F. Khan, E. U. Khan, N. Ali, N. U. Khattak ,I. A. Raja. Radon monitoring in soil
gas along active Balakot-Bagh fault line in Balakot-section. Presented at 2nd
International Conference “Environmentally Sustainable Development”, ESDev-
2011, held on August 24-26-2011, at Abbottabad (submission No: BE-02).
xxiii
9. F. Khan, E.U. Khan, N. Ali. Seasonally Variation in indoor Radon in Abbottabad
Pakistan. Presented at IOHA 2010 (Oral, Poster). Scientific program of 8th
International Scientific Conference HEALTH, WORK AND SOCIAL
RESPONSIBILITY.
10. F. Khan, E. U. Khan, N. Ali, H.A. Khan, I. A. Raja. Estimation of annual mean
dose from indoor radon concentrations in Abbottabad, Pakistan. Presented at 2nd
International Conference “Environmentally Sustainable Development”, ESDev-
2011, held on August 24-26-2011, at Abbottabad (submission No: BE-01).
11. F. Khan, E. U. Khan, N. Ali, N. U. Khattak , I. A. Raja. Radon monitoring in soil
gas along active Balakot-Bagh fault line in Balakot-section. Presented at 2nd
International Conference “Environmentally Sustainable Development”, ESDev-
2011, held on August 24-26-2011, at Abbottabad (submission No: BE-02).
12. F. Khan, I. A. Raja, E. U. Khan, N. Ali. Comparative study of indoor radon
concentrations for different types of material. Accepted for presentation at 5th
International Conference “Environmentally Sustainable Development”, ESDev-
2013, to be held on August 25-27-2013, at Abbottabad (submission No: BE-01).
1
CHAPTER 1
INTRODUCTION
Radon is one of significant source of natural radiation amongst the decay series
products. The contribution in the natural background radiation from Rn222 alone is
expected to 50-55% of the mean annual dose [1]. Radon was discovered in 1900 and
was used in many effects of human use from toothpaste to hair cream till the
association among lung cancer and radon was revealed in 1950s in uranium miners,
bare to elevated concentrations of radon gas for the period of their labor [2].
U238 is present in abundance inside the earth core. The ultimate source of
radon is the uranium in the soil. The decay series of uranium is shown in Fig. 1.1.
Rn222 emanates through earth crust, depending upon porosity of the structure.
However the geological faults in the various tectonic plates provide an easy path
to Rn222 for the migration to the surface in the area.
Radon gas enters into people's houses from underlying soil and building
materials, build up to high levels and may cause the occupants to die from lung cancer
after many years [3]. Water radon concentrations also contribute to indoor radon in
the ratio of 1: 104. The study of radon is also important as it is an excellent tool of
research in variety of fields such as deeply buried uranium traced by it [2, 4]. To
estimate the health risk posed by indoor radon and to use it as a helping tool, a
systematic approach has to be adapted. Besides monitoring indoor radon
concentration levels, its entry sources have to be identified. In addition to this,
understanding and modeling of radon transport is also crucial.
The northern part of Pakistan is situated at the cross roads of various tectonic
plates, and has different well defined faults; the probability of excessive Rn222 in the
area is very high. Radon has no direct or immediate health effects, but it decays into
short-lived daughter products that are in solid form. These daughter products are the
main health risk [5].
In the present work, the measurement of radon concentration in the water
sources, soil gas and indoor air were carried out in some of the earthquake hit areas in
Hazara Division, N.W.F.P (Khyber Pakhtun Khwa). It is most probable that there may
a considerable increase in the radon concentration in all these three media (indoor air,
2
water and soil). No study of radon concentrations in the area was conducted before
2005 earthquake. This study is therefore; equally important for the health protection
of the people of the area as the annual received doses were estimated from the
measure of radon levels. The current survey is also important as it provides the base
line data for future researchers in the field.
238U
234Th 234Pa 234U
230Th Alpha decay
226Ra
Beta decay
218Po
214Pb 214Bi 214Po
210Pb 210Bi 210Po
206Pb
Fig. 1.1: Diagram showing the Radon decay chain [6].
1.2 Objective
The work is aimed to determine radon concentrations in water reservoirs, soil and in
indoor air of the study area, situated in Hazara Division N.W.F.P (Khyber Pakhtun
Khwa) which was hit by a devastating earthquake in October, 2005. The rocks below
the soil are fractured due to earth quake and resultantly radon movement is affected
by diffusion as well as convection flow. Radon may also move with ground water in
dissolved state. In order to escape the rock and soil the radon must migrate relatively
quickly before it decays and progeny combines chemically with surrounding
elements. In area where soil has high porosity and permeability or is in proximity to
fractured rocks and fault lines, greater quantities of radon may reach the earth surface.
Likewise, radon formed in close proximity to ground water may dissolve in the water
and travel with it.
222Rn
3
Rn222 , α-emitting gas, is present in the environment especially in the region
where U238 is in abundance. We inhale it through our respiration system and emitted α-
particles can decay right in our lungs which may become a source for the lung cancer.
In all the radioactive nuclei, 45% contribution to the lung cancer is because of radon.
Though the excessive Rn222 in environment may be reduced due to precautionary
measures in the dwellings, there is still a possibility that Rn222 is dissolved in natural
water reservoirs. Hence it is significant to measure the Rn222 level in the water
reservoirs. Although many surveys have been carried out to measure Rn222 gas in
dwellings in settled areas of Pakistan, however no radon survey in water has been
conducted so far in any part of the country.
1.3 Thesis organization
This thesis comprises of seven chapters. The first chapter briefly introduced the work
done and the objectives of this study. The second chapter thoroughly reviews the
experimental efforts carried out throughout the world in this field. Chapter Three
describes the topographical and geological features, houses structure, climatic
condition and population of the area. Chapter Four describes the techniques used in
this field for the radon measurement. It also describes the relative advantage and
disadvantage. Chapter Five describes the experimental arrangements, while the
chapter Six describes the results and discussions and these results concluded in the
same chapter. Chapter Seven includes the future recommendations for the future
researcher in the field, on the basis of the current work.
4
CHAPTER 2
BACKGROUND AND LITERATURE REVIEW
The possibilities of Rn222 within the earth, its waters, and atmosphere make it a
valuable tracer for noteworthy range of geophysical, geochemical, hydrological, and
atmospheric purposes. These applications include searching of possessions for
instance uranium and organic deposits, studying gas course and mixing in the
atmosphere, to identify fluid transportation inside earth, in endeavor to forecast
seismic and volcanic proceedings resultantly premonitory variation in radon levels
within the earth. Alternatively, the presence of extra radon has special significances
due to its health threat as Rn222 is the second foremost reason of lung cancer following
cigarette.
2.1 Radon daughters
Radon decays into its daughters known as radon progenies starts from
polonium Po218 and become stable at its eighth daughter which is lead Pb206 . Radon
itself is considered to have no immediate effects but its progenies are responsible for
main health risk. The decay chain which originating from U238 is given below
PoRnRaThUPaThU 218222226230234234234238
StablePbPoBiPbPoBiPb 206210210210214214214
Due to longer half life (3.82days) of radon than breathing time, most of the
radon that is inhaled is exhaled without decaying [7] Negligible amount of radon gas
decay inside the lungs which can be ignored. The decaying progenies of
radon PoandBiPbPo 214214214218 ,,( ), being more chemically reactive, may attach to
particle surface (attached fraction), characteristically aerosols, which can be inhaled
and deposited in the nose or the pharynx (3% chance of adhering to the lungs lining);
the free fraction (ions) have chance (50%) of settle on the surface of bronchi[8].
Paradoxically, in dust free areas for the same radon levels; the risk from elevated
radon is lower than in dusty areas. While the top of the four, Pb214 , has a half life of
not as much of 27 minutes, the full series of decays is being concluded prior to the
5
usual clearance procedures of the lung can eliminate them away. Consequently the
susceptible surface of the bronchi are irradiated by these decays the mainly energetic
stern of which are the greatly ionizing short-range α particles from polonium
isotopes Po214 and Po218 while the third α emitter of Po210 contributes relatively little
because its decays needs the earlier decay of Pb210 having 22-years half-life [9].
2.2 Radon and Risk
Lung cancer is the principal health hazard of radon as it comes to the body through
breathing. The correlation among radon and lung cancer in miners has increased
apprehension that radon inside homes may be the source of lung cancer to the
common public, even though the radon levels in most of homes are much lower than
in mines. Serious epidemiological investigations have been realized on the health risk
but study related to the general public is fairly odd. The general public is exposing to
lesser levels of radon progeny than the workers in the uranium mines. Beside the
radon progeny levels, the miners exposed to the cigarette smoke which can also
contributes in the lung cancer. Supplementary differences relate to work state are
inhalation rate, nature of aerosol distribution, people characteristics such as gender,
age and relative lung working. Subsequently link of the results for the uranium miners
and general public is very complex and highly unsure. There are three common
models used for analytical connection between the dose of a cancer-causing
substances and the outcome (growth of cancer); (i) The linear model assumes that as
the dose increases there is a linear increase in the effect (cancer), (ii) The threshold
model assumes that there is no effect at all with a very low dosage but as the dosage
increases to a certain value (threshold) at which the effect (cancer)is seen and (iii) The
quadratic model assumes that at lower dose the effect decreases more rapidly than
dose. According to all these three models there is no health risk at zero dose and
some health risk at high dose as they all are based on the obtainable data such as the
underground miners studies. The dose- effect connection for high dose is practically
well recognized. The difficulties come up from making link between these data and
lower dose levels as the largest part of the people are exposed to, much lower
concentration than miners [10].
The acknowledged risk model of lung cancer by NCRP is based on data in
high exposure of underground miners. The projection to low- level exposure is
6
supported by epidemiological studies of lung cancer in non- smokers. Following
assumptions were made to develop these models:
No lung cancer occurs prior to the age of 40 years.
There is an inactive age of 5 to 10 years between the exposure and the
happening of cancer.
It is understood that after the age of 85 years there is no input to lung
cancer.
The chance of lung cancer decreases with the increase in age for a
particular exposure.
The level rate for lung for a single exposure is foremost when age at
exposure is highest.
The nucleus age linked with indication of lung cancer is around 60
years for non-smokers and 50 plus for smokers.
2.2.1 The life cancer estimate
The life cancer is calculated in the following manner [10]
First the annual danger is determined, following to an annual exposure of 1WLM at t0.
000, ttetCNttA (2.1)
Where 0, ttA = the chance of cancer generation at time t (t =40) due to a single
yearly exposure at t0
C is the risk coefficient per year per WLM
0tN is the number of WLMs of exposure at age t0
λ is the constant accounted for decrease in rate of risk of due to revamp, cell loss
or indeterminate means (λ= ln2/20yr-1)
Now the lifetime risk, R at the age of tm for manifold exposures is obtained by
summing the annual risk as follow;
mt
t tttAR
0
0
85),( (2.2)
Where t = 40 to 85 for t0 < 35, and t = (t0+5) to 85 for t0 >35
7
2.2.2 Excess of Lung Cancer Risk
The excess of lung cancer risk is defined as the incident of excess deaths per million
people per (MPY) due to the lung cancer as a consequence of revelation to radon and
its progenies. The risk coefficient, defined as the quantity of lung cancer cases per
MPY per working level month (WLM) is calculated using the epidemiological
records of the occupationally exposed mine workers. A statistics is obtainable for lung
cancer cases owing to the inside radon exposure as can be seen in references [11-15].
According to this information, the risks emerge to be regular by the previous
approximate that are based on the records of mine workers. So whenever the lung
cancer risk is measured because to the indoor radon exposure, the data of mine
workers is frequently deemed. There are numerals models for calculations of the lung
cancer risk owing to the indoor radon exposure have been given in the text [16-19].
The excess of lung cancer per MPYas a function of the indoor radon
concentration level is given away for the risk coefficient of the scheduled agencies in
Fig. 2.1 It can be seen that there is a large disparity among the probable values of the
excess lung cancer risk. The excess lung cancer risk calculated using the
UNSCEAR upper limit of the risk coefficient is the uppermost conversely; the lower
limit of the risk coefficient recommended byUS EPA capitulate the lowest excess
lung cancer risk value. This is because that unlike assumed parameters were used in
the models planned by the above- stated organization whose reliability is not sure for
the reason, that of the non-availability of the requisite information concerning the
deaths owing to the lung cancer arise by indoor exposure to radon and its progenies.
Using these models a probable calculate approximately of the lung cancer risk is
possible.
It is appealing that the approximation of lung cancer risk per WLM published
by theUNSCEAR andUS EPA are based on the Western populations. The numerical
models derived from epidemiological data must be taken for suitable risk
measurement by considering the statistical error in mind. The lung cancer risk due to
tobacco usage and due to radon cause per WLM fluctuates in different inhabitants
[11].
A complete calculation of risk for people of a specific area would entail
information of the age–specific lung cancer rates and on the whole death rates in the
populations. If such information is not available then it is suitable to use the risk
8
coefficient reported by EPAUSandUNSCEAR . The excess lung cancer risk is
measured by means of the following relation [20],
RiskCancerExcess = WLMfactorrisk 8.05.0 (2.3)
Where 5.0 is the factormequilibriu and 8.0 is the residence part (the part of moment
used up indoor).
Fig. 2.1: Excess lung cancer risk as a function of indoor radon level
2.2.3 Radon in Water
Radon is produced from the radioactive decay of uranium and radium deposits.
Almost in all soils and rocks uranium and radium can be found, in draw amounts. As
radon is gas, so it can get away from mineral outside and dissolve in ground water,
which can transmit radon from the position of derivation to any other point. Radon
concentration is not found, considerably in surface water, owing to its quick diffusion
into the environment.
Usually groundwater sources have mean concentration between 200 and
600 1lpCi more or less 10percent of community drinking water provisions have
concentrations greater than 1000 1lpCi and approximately1percent exceeds
0 20 40 60 80 100 120 140 160 1800
20
40
60
80
100
120
140
160
180
200
220
240
260
0
20
40
60
80
100
120
140
160
180
200
220
240
2600 20 40 60 80 100 120 140 160 180
UNSCEAR (uuper limit)EPA (upper limit)
BEIR IV
UNSCEAR (lower limit)
NCRP 1984
EPA (lower limit)
Exc
ess
Lung
Can
cer
Mill
ion
Pe
r Y
ear
(MP
Y)
Radon concentration (Bq m-3)
9
10,000 1lpCi . Slighter water systems come out to be disproportionally influenced by
elevated radon [21].
J.J. Thomson was the first one to discover radon in water stores, break a new
ground in the discipline of radioactivity, in the start of nineteen century [22]. In the
beginning, scientists and doctors thought radioactivity to have kind, still remedial,
outcomes on the person cadaver. Untimely study connected elevated radon levels to
innate warm spring's wide attention to have marvelous powers. However later,
knowledge proved the threats of radiation revelation, following a numeral of solemn
mishaps and victims [23].
2.2.4 Health risks due to waterborne radon
In the 1950s the radon decay yields in air appeared as the possible reason of soaring
occurrences of lung cancer amongst underground mine workers. Further works
exposed usually elevated groundwater radon levels in the surrounding area of
Raymond, Maine. In the 1960s, scientists started to study the result of ingested and
breathe in radon gas, monitored the radon taken by digestive organs and its dispersion
throughout the bloodstream [24]. Till 1970, radon was generally acknowledged as
most important part of our natural radiation exposure. By the overdue 1970s, Maine
had started a plan to endeavor to diminish community exposure to radon from water,
having revealed cases in which groundwater concentration greater than
1610 lpCi [22].
Federal action in USA, on the crisis of the radon in drinking water focused in
the 1980s with a countrywide plan to study consumption water stores for radioactivity
and estimate the danger to community health. The Environmental Protection Agency
)(EPA had been directed by Congress, to take notice of radioactivity in drinking
water, in this regard, in 1991 the EPAUS formally projected a Maximum Contaminant
Level(MCL) for radon in community drinking water of 300 1lpCi (11.1 3mkBq ).
This )(MCL could one day turn into bind on community water supplies [25].
Radon due to water go ahead to health danger by two ways: first the radon and
its progenies inhalation, subsequent the discharge of radon gas from water into family
unit air, second the straight intake of radon in drinking water.
10
The hazard of lung cancer owing to inhaled radon progenies has been well
recognized during the survey of undergrounds mine workers. The cancer risk due to
intake, mainly includes, abdomen and digestive organs cancer. This has been
projected from survey of the movement of radon through the gastrointestinal zone and
bloodstream. So far cancer is the only health hazard associated with radon than any
other disease. The cancer risk from the inhalation pathway is more than from the
ingestion pathway [24].
In the majority of houses, radon from water is less important source of inside
radon, than by soil gas flow. It is a known belief, although not an unusual one, that
radon from water is the main provider to high radon in air [26].
2.3 Soil gas radon
A radon level in outdoor air is due to the exhalation rate of radon gas from the upper
soil. It is so reduced that its concentration is insignificant at knee-height is of the level
(8-14 3mBq ), exceptions are present. Special metrological circumstances could favor
the keep on the radon gas in situ in the open air. The radon gas spreads only by
dispersal of its atoms. The radon gas stays in the air above the point of exhalation,
giving radon concentrations of the order of 100 3mBq due to inversion condition.
The occurrence of the radon progenies in the air is extremely unpredictable due to
dilution of radon gas.
The concentration radon in the soil depends on soil depth. It rises with depth,
and could achieve a limit at a depth of about 2 m in the soil. Generally there is a
rupture in the increase of the radon concentration at a depth of 2 m. The upward move
of the radon gas is because of diffusion and forced transfer, which elucidate a long
distance transport of radon [27, 28]. One likelihood is a mover gas, like bubbles
stirring upwards through water-filled snaps. One more is a force upshot by
compression and decompression in the ground, probably in link with seismic
activities. The radon concentration zC at depth z in the soil can be illustrated in
theory by the expression:
zC = kzeC 10 (2.4)
Where 0C is constant and
11
k =
DD
v
D
v 22
2
42 (2.5)
With as the porosity of the ground medium, v as the flow velocity D as the diffusion
coefficient, is the radioactive decay constant.
The complication of the radon carrying shows that its level increases with
depth in the sand [27]. Usually, the depth dependence of the radon concentration is
dissimilar in diverse kinds of the soil. The porosity is a significant factor since it
fluctuates from one type of soil to another [29]. A second key factor is the diffusion
coefficient [30]. The radon concentration with respect to moisture in the soil shows
that the radon level for the most moisture is less as compare to the low moisture soil
for the same thickness and same nature of the soil [31].
The uranium content of the soil is imperative for the nearby formed radon gas.
The uranium content is one more main parameter along with the porosity and
diffusion coefficient [32]. A growing range of the uranium content shows a higher soil
radon level which is based on a biogeochemical mapping technique. (1-25 ppm) [33].
To get a better impending, the contribution of soil in the radon concentration
the study has been carried out in the Hazara division in all three media indoor air, in
sources of drinking water and in the soil, especially in the earth-quake hit area as it is
expected that the radon concentration may be increased after the earth-quake and a
high radon concentration is observed with soils lying over extremely cracked rocks
such as geological faults and active volcanoes [34-37].
2.4 Indoor radon sources
The soil adjoining to the construction, drinkable water supply and construction
materials are the main sources of radon and its progenies [38]. Radon in outdoor may
also enter in the building as the air exchanged. Yet this is usually balanced by the loss
of radon to the outside as the indoor radon concentrations are typically higher than
those outside the structure. A natural gas usage can also contribute very small in the
indoor radon concentration as contrast to the other sources. Categorization of the
indoor sources of radon requires consideration of the rate at which radon is generated
in the source materials and its form of transport through different materials which will
be discussed later.
12
Radon can move in to houses through cracks or holes in the groundwork from
the soil gas near buildings. This also provides a fractional justification for the
observed higher radon levels in the basements and on ground stories as compared to
upper stories. The key factor may be the typical air exchange pattern.
In general buildings materials contribute very little except when the radium
contents in it is above the usual values. Many of the building materials such as
concrete or wallboard and the bricks are adequately permeable and allow radon to
enter into the indoor air. Materials which are not derived from the earth's crust, such
as wood, tend to have very low radium concentration [39]. As a result radon
concentrations in dwellings to a certain extent depend on construction practices and
materials used.
All of the radon produced from the radium in the soil and building materials
cannot migrate and enter into home. Some of the radon atoms are ensnared within the
grains of soil and are not able to escape to pore spaces [40]. The un-trapped radon
somewhat absorbed in ground water and some diffuses through the soil. The radon
concentrations in soil gases and dwellings primarily depend on the emanation and
exhalation rate of radon respectively, besides some other parameters.
2.5 Literature review
2.5.1 Radon concentration in water
Radon level in the ground water and its variableness with time and space has been
calculated often in modern time. The outcomes of the investigation are extremely
significant for radon movement processes in the lithosphere and the job of
groundwater as radon transporter fluid. It is too imperative to identify the function of
geological formation and rocks kind as a cause of radon dissolved in groundwater
[41-63]. For that reason, it is doable to decide regions where one could suppose
groundwater steady flows with high radon concentrations. Moreover, it is probable to
employ such outcome for applying radon as a natural radioactive tracer of various
developments occurring in hydrosphere (in groundwater and surface waters,
predominantly in the zones of their mixing--- for instance, Karst areas) and
lithosphere [64-74].
The levels of radon vary in different types of water (spring, bore and surface
water). By and large very low radon concentrations are found in surface water, the
13
levels in the range of a small number of 3mkBq [75]. At the same time as the highest
concentrations of dissolved radon are found in ground water flowing through granite
or granitic sand and gravel arrangements, ranging from 1-50 3mkBq in aquifer and
sedimentary rocks, 10-300 3mkBq in very deep wells and 100-50000 3mkBq in
crystalline rocks [76, 77]. The data of radon concentration from 300 samples
composed from 41 states of USA showed that the average value of radon
concentration ranging from 1.24 3mkBq in Tennessee to 65.6 3mkBq in Rhode Island
[40].
The radon concentrations in hot spring water hotels in Guangdong, China ranging
from 53.4–292.5 3mkBq [78]. These values obtained for faucet water in Baoji, China
were 12 3mkBq and 41 3mkBq for different water sources [79]. The radon levels in
drinking groundwater and in surface water in Tehran, Iran were 50.1140.46 and
20.150.2 1lBq correspondingly. The average radon level in faucet water was
94.070.3 1lBq [80].The radon concentrations were measured in the faucet water,
spring water and in the river water in the area of Tokat city in Turkey. These values
are ranging from 22.048.0 to 27.03.1 1lBq from 17.013.0 29.020.1
1lBq and from 12.009.0 to 17.083.0 1lBq in faucet water, spring water and
Yesilirmak river water correspondingly [81]. The radon concentrations in
groundwater were measured at diverse points located in Tassili (Algeria). It varied
from 0.50 to 19.3 1lBq [82]. Radon concentrations in the ground water of
Uttarkashi, India over and around the landslide were in the range of 0.51 to
86 3mkBq [83]. The radon levels in the hot spring water in the Venezuela are varying
from 1 to 560 3mkBq [84]. The radon concentration values in groundwater of the
Polish part of the Sudety Mountains (SW Poland) are ranging from 0.2 to
1645 3mkBq , with the mean value of 240.0 3mkBq [85]. The survey carried out for
the radon level in natural water in the Transylvania region in Romania. The study
revealed that the radon levels are within the range of 0.5-129.3 3mkBq with average
value of 15.4 3mkBq for all types of water covered in the survey [86]. The radon level
in ground water is usually to a large extent, higher than it is in surface water [87].
Typical values of radon in surface water are around 40 3mBq , while in ground water
14
it ranges from 4 to 40 3mkBq table (2.1) shows the radon concentration in various
part of the world [19].
Quantity of radon in natural water provides valuable information regarding the
uranium deposits and in addition to this it helps in searching hidden fault. While to
protect from the radiation hazards and to differentiate between ground and surface
water, over and above, to look for seismic linked variation in the radon contents of
water, constant check of radioactivity in drinking water, mineral water and thermal
water is required [52, 88].
There are many technique and instrument through which radon concentration
in water can be measured. The most appropriate method for the study of partition
patterns in the groundwater or surface water sources is the active method through
which in-situ measurements are obtained [89].
Table 2.1: Radon in water in different parts of the world.
Country/location Average radon concentration ( 3mkBq ) Austria Saizburg
1.5
Finland Helsinki and Vantaa Other areas
1200 280
Italy 80 Sweden 19 United states Aroostock, Maine Cumberland, Maine Hancock, Maine Lincoin, Maine Penobscut, Maine Waldo, Maine York, Maine
48 1000 1400 560 540 1100 670
2.5.2 Soil gas radon concentrations
The soil radon level is related with the occurrence of Ra226 and its final source
uranium in the earth crust. Though these elements come about in all kinds of rocks
and soils, yet their level fluctuates with particular locations and geological substances.
The half life of the Rn222 is 3.82 days, and being an inert gas it can travel great
distances all the way throughout rocks and soils. Therefore radon is, equally, a danger
as well as helpful [7]. As radon transports through waters within earth and atmosphere
this ability of radon formulate it a valuable tracer for a noteworthy range of
15
geophysical, geochemical, hydrological, and atmospheric uses[90]. These uses
include searching of possessions such as uranium and hydrocarbon deposits, studying
gas flow and integration in the atmosphere, recognizing fluid transport inside the
earth, attempting to forecast seismic and volcanic actions through premonitory
variation in radon concentrations in earth [77, 91]. These uses of radon make it useful
even than its health hazards. A constant exposure of individual to elevated levels of
radon yields possibly will create lung cancer, hence radon measurement play a vital
position in examine individual health and protection, together in homes and mines.
Radon concentration measurements in the soil is important for many reasons
first, is to sort out houses with high indoor radon levels. The further cause is particular
building regulations. The radon must be prevented from entering the house from the
soil and the constructor of fresh house must consider that. In large-scale of soil radon,
many geological and other records are required; but there is no hesitation that regions
with elevated uranium content in the bed rock or in the soil are danger area as the
indoor radon concentrations values are correlated with predominantly soil radon gas
[92].
The time-dependent changes in the soil radon levels are generally of two
kinds: Long-time variations and short-time variations. The long- time variations are
provisioned by parameters of seasonal nature. Such parameters are ground-water
levels and temperature. The radon concentration is higher in one part of the year than
in the other part of the year [93]. One possible factor disturbing the calculated radon
concentration is the ground water level, which could be soaring in the autumn or in
the winter. An additional likelihood is the result of lower temperature.
For porous soils the ground water levels has less weight; as compare to clay
[94]. Soil radon measurement has to be done at certain depth that is not affected by
temperature.
It is obvious from above discussion so as to soil radon level depends on, a
number of parameters. A few of these parameters and their outcomes have been
discussed above. Numerous of the parameters have a geological or a metrological
origin. Occasionally one parameter controls the radon concentration in soil greatly at
one position of measurement, but only a few meters away this influence could be
insignificant [27]. This information makes it difficult to identify or estimate the soil
concentration, particularly if one or two central parameters are unidentified. It is then
16
easy in a given measurement to incorrectly indict the soil radon detector for giving the
incorrect reply.
Building materials, adjacent soil and faucet water if it is supplied from the
groundwater in radium behavior aquifers, are the major sources of indoor radon
levels. The contribution from the tap water and building materials is not significant it
make only a small fraction of all radon sources. Therefore the most important source
is the underlying soil [95].
The soil-gas radon level was in the range of 3 to 219 3mkBq and it was found
high in active landslide area of Uttarkashi, India [83].
2.5.3 Indoor radon concentrations
A very detailed study has been carried out for indoor radon levels and radon in
workplaces throughout the world in the last 30 to 35 years. Regardless of the large
research work which had been done on radon there is still a room for further
investigates from the radiation safety point of view.
One of the most primitive works associated to radon measurement in Pakistan
was reported elsewhere [96], where CA80-15, LR-115 and cellulose nitrate detectors
were used. They had calculated the annealing properties of the latent damage tracks
created by the particles emitted from radon and thoron.
Radon may be utilized to foretell the coming of volcanic and seismic
activities, to locate the uranium and oil deposits [28, 97, 98]. In this regard, radon
signals were used to guess the coming of an earthquake, to trace geothermal energy
sources, oil and uranium deposits [99, 100]. The radon variations were being
monitoring frequently to develop an earthquake caution signal method. For the first
time radon was used, in measuring radioactivity in the area of Kirana hills, Punjab
Pakistan and to look for the uranium ore deposit in the area [101]. The radium and
uranium in various ore samples can be measured from radon exhalation rate for the
collected samples from different parts of Pakistan [102]. Alpha Sensitive Plastic Film
)(ASPF method can also be used for the earthquake forecast and for the site of re-
mobilized uranium ore bodies in sand stones [103-105].
Largely CN-85, CR-39, LR-115, etc were used for the radon measurement in
order to evaluate the radiological risks to the job-related workers in the underground
mines; the radon measurement study has been carried out in some of Baluchistan coal
mines. In this survey passive technique was utilized in which 85CN track detectors
17
in box type dosimeter were used [106]. The utility of an alpha sensitive plastic
SSNTDs for radon measurements were quantified in the experimental work [107]. The indoor radon concentration level besides others factor depends on the
porosity in the building materials and diffusion length of radon. In this regard, the
diffusion length, porosity of soil and sand has determined by means of
39CR detector [108]. Track dosimeter in combination with mica nuclear filters was
used in some fundamental experiments to measure the radon track densities in a
diverse atmosphere of radon and thoron have been reported [109].
Radon study has been carried out in the Makarwal coal mines of Pakistan by
both passive and active techniques [110]. In this study passive technique CR-39
detectors were used at different positions in the mines and in the active technique an
air pump was used for drawing the air through a filter paper. The radon decay
products were then trapped by the filter from which the alpha activity counted using
Thomson and Kusnetz techniques. The equilibrium factor dependence on the
shape/effective volume of the chamber has studied in using the SSNTDs and surface
barrier detectors in Karlsruhe Diffusion Chamber (KDC) [111]. The majority of the
works, on the subject of radon concentration level measurement have been done in the
residential area of the Pakistan. Few survey have also been carried out to find out the
work-related radon danger. Indoor radon has measured in other study by means of
CR-39 and CN-85 detectors [112].
In one of the study, carried out in the mines of Chakwal and Makarwal regions
of Pakistan high radon concentration level was observed in poor ventilated mines. In
this survey closed-can technique was used to measure radon exhalation rate from
shale and coal samples which were accumulated from different mines [113]. Radon
concentrations were measured from the samples composed from different coal mines
in the Punjab and Baluchistan regions of Pakistan using hybrid technique and CR-39
trail detector [114].
The largest part of the houses in Pakistan is mostly made from soil, sand,
bricks and marble, etc. Hence, study of radon exhalation rate from the aforesaid
construction supplies is very important. For the reason the soil samples were
composed from the seven cities of Bahawalpur Division and four metropolis of
N.W.F.P (Khyber Pakhtun Khwa) in which radon exhalation rate have calculated
[115]. In an another study, radon exhalation rate have measured in soil, sand and
18
bricks samples, composed from the North West Frontier Province (N.W.F.P) and
Federally Administered Tribal Areas (FATA), Pakistan [116].
As it is stated previously that in Pakistan a large amount of the radon
measurement related available figures is about indoor radon measurements. The
radon/thoron concentrations were measured in Lahore and Kasur cities by using
85CN (SSNTD) pipes from which radon flux; concentration and annual dose have
been calculated [117]. In Skardu city, northern Pakistan indoor radon concentrations
were measured [118]. A related survey has been reported in residences of the Jhelum
valley, Azad Jammu and Kashmir [119]. In one more survey, the indoor radon level
has calculated in the city of Muzaffarabad and in the Rawalakot areas of Azad Jammu
Azad Kashmir [120, 121].
CR-39 and CN-85 detectors have been utilized in measuring indoor radon and
its progenies in Islamabad, in bed rooms, kitchen and drawing rooms of the houses
[122]. A similar sort of study have done in Islamabad, Lahore and Rawalpindi cities,
using CN-85 trail detectors in container kind dosimeter [123]. In one of the survey
internal, external doses were estimated from radon concentration measurement, and
gamma ray activities in residences of the Dera Ismail Khan [124].
Indoor radon concentration levels have measured in seven major cities of
Bahawalpur Division, using CR-39 detectors in polythene bag [20]. Radon level has
been measured for the Islamabad and Rawalpindi cities by means of SSNTDs and
from these data the lung cancer risk have been determined [104]. Similarly radon
concentrations have been measured in the new and old buildings of the Fatima Jinnah
Women University )(FJWU campus, Rawalpindi, Pakistan [125]. CR-39 based
NRPB dosimeter have used for the indoor radon concentration in numerous districts
of the North West Frontier Province ( PFWN ... ) and federally administered tribal
areas )(FATA Pakistan [116]. In one more survey, seasonal variation have measured
in the indoor radon concentration levels in the same region taking four set of
measurements round the year [126]. Indoor radon concentrations calculated in the six
districts of Punjab from which seasonal correction factors have obtained for the region
[127].
A lot of literature is available on seasonal deviation of indoor radon
concentrations. The concentration of radon and its progenies confirm large time and
local variations in the indoor atmosphere due to the variations of temperature,
19
pressure, nature of construction supplies, ventilation circumstances and breeze rate
[128].
In general winter season shows elevated radon concentration than in summer
means that better ventilation is adopted, in principle, by the dwellers in summer. For
example, In the U.K, correction factors have been anticipated for seasonally
normalizing radon values [129]. Yet, this rule, whereas recounting an average
behavior could not be valid in individual's case and can lead to incorrect
approximation of the annual average. Even this rule does not hold for the residences
located on the slope [130, 131]. In this regard, a survey has carried out in Poland in
which a large number of buildings investigated, show negative long term correlation
between radon and temperature; however, some showed the opposite behavior [132].
In another survey which was carried out on monthly basis, indoor radon levels
were measured in three houses over a period of 2 years and on different floors. A
sturdy seasonality was for ground and first floor, with high radon concentrations in
winter, and negative link with outside temperature have confirmed [133]. The study
which was carried out in several houses of Greece for indoor radon levels confirm that
the radon level is changing with the floor level. This study further reveals that in
winter season the radon concentrations are highest and varies with the floor level
[134].
A recent study carried out for indoor radon concentrations subjected to
seasonal changeability at different floors of buildings southern part of Italy. It reveals
that the atmospheric pressure does not show to be a noteworthy control, changeable
for indoor radon in any case on an annual basis. From this study higher radon
concentrations were observed in rainy season and lower in dry season. For the
uniform condition of the soil, geology and uniform climatic condition the trend shows
that a high indoor radon concentration on the first floor and lower on the second
[135].
According to EPAUS , long-term test for determination of indoor radon level
must be more than 90 days and that short-term must be less than 90 days [136]. As
different studies have also revealed a considerable variability in indoor radon levels,
both on an each day and seasonal basis, however it is not always easy to explain the
exact reasons [137-140].
20
The construction materials in the houses play a significant task in the indoor
radon concentrations for the same condition (metrological, geological and soil nature)
the mud made houses have high indoor radon concentrations than bricks made and
concrete made houses [141]. A similar behavior was observed by others [142]. The
adobe walls and floors have the highest indoor radon concentrations [92].
Most of the work in Pakistan was carried out for indoor radon levels using
passive technique; however a very little work has been carried out for soil gas radon.
There exists hardly any work studying radon concentration in water before the present
work.
21
CHAPTER 3
GEOLOGY AND DEMOGRAPHY OF THE
STUDY AREA
As the radon, natural radioactivity, their hazard, and the measurement techniques are
discussed in the previous two chapters now it would be useful to discuss the salient
features of the selected area. The selected area is the Hazara Division in the N.W.F.P (
or now Khyber Pakhtun Khwa) - Pakistan (Fig.3.1), hit by the earthquake in October,
2005. It includes five districts namely Abbottabad, Mansehra, Haripur, Battgram and
Kohistan which are shown by the shaded areas in Fig. 3.2. Khyber Pakhtun Khwa is
the province of Pakistan which is 12% of the hole populace of Pakistan from 1998
census details. The selected area corresponds to 20% of the total inhabitants of the
N.W.F.P (Khyber Pakhtun Khwa) and approximately 3% of the total population of
Pakistan. A short narrative of Hazara Division and apiece district is discussed below.
Fig.3.1: Map of N.W.F.P with black shaded portion of Hazara Division (study area)
22
Fig.3.2: Map of the study area
3.1 Lanform of Hazara Division
In Hazara Division the landform between Hassan Abdal and Thakot mainly consists
of reworked loess and alluvial deposits [143]. These deposits occur in the form of
terraces and overflow plain deposits beside the vale slopes and banks of the major
streams in the region. These alluvial plains are well developed in the low lands of
Haripur, Abbottabad, Hassan Abdal and Battgram regions, but inadequately
developed in the highlands connecting Mansehra and Shinkiari. The loess is partially
consolidated and interlayered with sandy gravel. Small alluvial pieces are there beside
the highway, which are poised of gravel and boulder deposits. The Batal alluvial
deposits of are composed of to some amount, customized and weathered material
resulting in Mansehra granite.
The Thakot-Gilgit part of the thoroughfare consists of sharp inclines and
cavernous ravine. The geography of this region is irregular and rough. A large range
of igneous and metamorphic rocks is revealed in the vicinity that has undergone
widespread deformation owing to the soaring degree of tectonic movement
exceptionality of the area. One or more times this area has been glaciated. Glacial
sediments comprise interbedded glaciofluvial and morainic deposits with less
common happening of glaciolacustrine material. Surficial materials occur to a large
23
quantity in glacially deposited terraces in the river valleys, as alluvial fans at the
convergence of the Indus River and its streams, and as newly deposited alluvial stuff
in and along the riverbed.
3.2 Abbottabad
The Abbottabad district lies between 34.150 º N latitude and 72.58 º to 73.51 º E
longitude 1998. In north-east it touches the Punjab province through Murree hills and
Muzaffar Abad of Azad Kashmir. In south-west Haripur district, and in the north the
Mansehra district. The district covered an area of 1976 square kilometer. The district
includes two tehsil namely, Abbottabad and Havilian.
3.2.1 Physical features and topography
Abbottabad is the main city of Abbottabad district in the Khyber Pakhtun Khwa. It is
situated 205 km from Peshawar and 150 km north of Islamabad, at height of 1236 m
above sea level. The adjoining areas are Mansehra, Muzaffarabad, Haripur,
Rawalpindi, to the north, east, west and south respectively. The city is a part of the
Orash Valley, enjoy the pleasant weather. The city has educational institutes of high
values and military establishments. The people come in summer from all parts of the
country and even from abroad to Abbottabad.
3.2.2 Geology
The Abbottabad region is underlain by Pre-Cambrian to Cretaceous partly
metamorphosed sedimentary rocks [144]. The Cambrian rocks are pushed
southeastward above the Pre-Cambrian rocks of Hazara and Tanawal Formations
beside the Panjal Thrust, and are unconformably overlain by Jurassic to Cretaceous
Formations [145]. The Cambrian rocks in the survey region are separated into two:
below and above, the Abbottabad Formation and Hazara Formation respectively. The
Hazara Formation is overlain unconformably by the Samana SukLimestone of
Jurassic era. The Phosphorite mineralization is found at two horizons; the upper and
lower surrounded by Abbottabad pattern. Close to Abbottabad there is a component of
cohesive soils (clays) underlying a previous marshland and the water table in this
component is within 1-2 m of the ground surface [146].
24
Abbottabad’s rocky ground is rich in minerals, containing deposits of biotite,
granite, limestone, phyllite, schist, slate, soapstone and quartz. These mineral soils
occur as residual deposits in the hills and alluvial deposits on valley floors. Most of
the soil is grey in color (under moist forests) and coarse in texture. The soil is formed
by snow deposits as well as water and sedimentary rock and is mostly dry-farmed for
subsistence cropping. Farm soil may be classified into four categories:
a). loam and clay, mainly non-calcareous;
b). loam, steep and shallow soils (humid mountainous region);
c). loam and clay, partly non-calcareous with loess traces; and
d). loam with stones, and shallow (sub-humid mountain region).
3.2.3 Climate
The weather of the Abbottabad district is very pleasant in the summer and very
freezing in the winter. The winter starts from the month of October continues till mid
April. The summer starts in June continues till end August with average temperature
of 38 ºC. In the month of December, January and in even February the temperature
reaches below the freezing point because of snow fall most on top of the hills of the
areas and least on the city of Abbottabad. The remaining months of the year are very
pleasant due to frequent rainfall and wind blowing. The average annual rain fall in the
district is more than 1000mm in which the hilly area receives more than urban.
3.2.4 Population
The official population of Abbottabad district stands 0.928 millions according to 1998
census.
3.2.5 Construction Materials
Baked bricks, cemented blocks and shapes stones are the main construction stuffs
used in the structure of the outer walls in entire urban and rural area. Table 3.1
provides the detailed data on the construction materials used walls. However in most
of the rural areas the homes are made of wood and the mud combination. About 40%
of the housing units used reinforce cement concrete or bricks (RCC/RCB) other
details are revealed in Table 3.2.
25
Table 3.1 Construction materials used in the outer walls (%) of the Abbottabad district.
Walls materials All area Rural Urban Baked bricks/Blocks/Stones 84.4 73.6 95.2 Un-baked/bricks/Earth Bounded 12.3 20.7 3.9 Wood/Bamboo 2.9 5.1 0.7 Others 0.4 0.6 0.2
Table 3.2 Construction materials used in roofs (%) of the Abbottabad district.
Roof materials All area Rural Urban RCC/RCB 46.6 14.3 78.9 Cement/Iron sheet 9.2 3.7 14.7 Wood/Bamboo 9.2 3.7 5.7 Others 1.3 1.9 0.7
3.3 Mansehra
The district lies between 73.19º to 73.68º east longitudes and 34.56º to 35.12º north
latitudes. It is situated in Khyber Pakhtun Khwa province with an area of about of
4600 square kilometers. Abbottabad, Battgram and Kashmir lie to the South, North
and West of the Mansehra respectively. Mansehra district is divided into three
administrative areas; Tehsil Mansehra, Tehsil Oghi, Tehsil Balakot and one tribal
administrative area Kaladaka (recently got a position of district with name, Turr
Ghar).
3.3.1 Physical features and topography
Topography is rugged in the hills and foothills: however, in the plains it is regularly
uniform. The valleys and foothills have been greatly dissected in to depths and ridges
because of water erosion over the time. The track is composed of mountains to its
north and northwest with mark variation in altitudes. The highest peaks are"Musa-ka-
Mussala" (4075m) on the northeastern boarder with Kaghan Valley and "Churku"
(4285m) over looking Allyee Valley.
3.3.2 Geology
The western portion dominantly consists of upper Cretaceous to Eocene Mansehra
Granites and Ordovician Tanawal Formation. The eastern and northeastern portion
has many different rocks and geological structure. The most important of these
structures is the Hazara Kashmir Syntaxis. The syntaxis contains Murree Formation of
26
Miocene age in its core and Salkhala, Abbottabad, Kingriali, Panjal and Samana Suk
formations of Precambrian to Jurassic rocks on its limbs. On the rim of syntaxis
Salkhala slates of Precambrian age are exposed. The Salkhala Formation is thrusted
over Tanawal Formation of Ordovician age. The different units of the syntaxis are in
faulted contact with one another along Murree fault and Panjal fault [147-149].
The northeastern part of Mansehra district contains dominantly Salkhala Slates
with subordinate Kingriali and Panjal formations. Near the contact with Kohistan
district Jijal/Sapat ultramafics, Jijal/Sapat granulites and Kamila amphibolites
outcrops. The Jijal/Sapat ultramafics, Jijal/Sapat granulites and Kamila amphibolites
are thrusted southward over Salkhala, Kingriali and Panjal formations along Main
Mantle Thrust. Besides these large scale structures there are a number of mesoscopic
scale faults and folds in the Mansehra district [148].
The soils of Mansehra region are poised of metamorphic rocks and silts of
mica granite, like in the north-western parts of Abbottabad [150]. Usually, the valley
soils are productive and alluvial, and are; consequently, able to maintain fruitful
agriculture and the hilly soils are thin, steep and barren, except transformed to terraces
and irrigated.
Balakot area of district Mansehra, severely damaged from October, 2005
earthquake. Most of the area of Balakot lies on the Balakot-Bagh fault line known as
B-B fault line. The northwest-striking B-B fault was the cause of the 8 October 2005
earthquake of 7.6M. This fault line had been mapped by the Geological Survey of
Pakistan before the earthquake but had not been identified as active, apart from, 16
km piece near Muzaffarabad [151].
The Fig. 3.3 show the B-B fault line in the Hazara-Kashmir Syntaxis [152]
and Fig.3.4 shows the mapping of the sampling sites near the B-B fault line.
27
Fig. 3.3 : The Balakot–Bagh(B-B) fault in the Hazara–Kashmir Syntaxis.
28
11
Fig.3.4: Mapping of the sampling sites near Balakot-Bagh fault line
3.3.3 Climate
Mansehra remains warm in summer and cold in winter. While the northern part like
Naran, Kaghan etc remain even cold in summer due the snow covered mountains in
the area and very cold in winter. The total annual rainfall of the district is about 8640
mm. Temperature varies from 2 ºC to 36 ºC in the district.
3.3.4 Population
According to the available sensor data of the year 1998 the population of the district
was 1.152 million; the current growth rate is 2.4 per cent. The population density is
252 persons per square kilometer.
3.2.5 Construction materials
Baked bricks, cemented blocks and shaped stones are the main construction stuffs
utilized in the structure of the outer walls in largely in the town area and smallest
29
amount in the rural area. In the rural area the mud made walls and houses are also
found abundantly. The details of construction materials used in the housing units in
the outer walls and roofs are revealed in Table 3.3 & 3.4 respectively.
Table 3.3 Construction materials used in the outer walls (%) of the Mansehra district.
Walls materials All area Rural Urban Baked bricks/Blocks/Stones 84.4 73.6 95.2 Un-baked/bricks/Earth bounded 12.3 20.7 3.9 Wood/Bamboo 2.9 5.1 0.7 Others 0.4 0.6 0.2
Table 3.4: Construction materials used in roofs (%) of the Mansehra district.
Roof materials All area Rural Urban RCC/RCB 46.6 14.3 78.9 Cement/Iron sheet 9.2 3.7 14.7 Wood/Bamboo 9.2 3.7 5.7 Others 1.3 1.9 0.7
3.4 Haripur
District Haripur is located in the Hazara Division in Khyber Pakhtun khwa. It is
situated at latitude 33º 44' to 34º 22' and longitude 72º 35' to 73º 15'. Haripur district
comprises of Haripur and Ghazi tehsils. The district is bounded on the north-east by
Abbottabad district, north-west Mansehra district, and west Swabi district and on the
south Punjab province, district Attock. The most of the part of the district is the plain;
however the hilly areas also exist in North West and east parts of the district. The total
area of the district is approximately 2000 square kilometer.
3.4.1 Physical features and topography
Haripur is the main city of Haripur district in the N.W.F.P (Khyber Pakhtun Kkhwa)
Province. It is situated 115 km north of Islamabad and 170 km from Peshawar, at an
altitude of 432 m. Hazara Division which is known for its pleasant weather and for
the tourism as a gate for the northern part of the Pakistan starts from Haripur. The soil
types district are Rohi (finest natural soil),Doshani or Missi (fine clay soil),
Maria,Tibba,Kallar (sour or barren clay) and Bela (raverine soil).
3.4.2 Geology
Geographically, Haripur is a gateway between both the Hazara and the Khyber
Pakhtun Kkhwa, and the capital Islamabad. The Haripur plain covers about 350
30
square kilometers. The Haripur plain is bordered by mountain ranges from three sides.
The southern portion of the Haripur plain merges with the Potohar plateau. The plain
is covered with alluvial deposits [153]. Alluvium mainly contains gravels and
boulders beside the left bank of River Doar. The area lying at the base hill of
Gandgher Range consists of piedmont deposits, which are mainly clay with small
beds of sand and gravels. Consolidated rocks exposed around Haripur ranges from
Precambrian to recent deposits. Hazara slates, Tanawal Formation and Abbottabad
Formation are predominant among them.
3.4.3 Climate
Climate of the district is very hot in summer and cold in winter. June and July are the
hottest months, while in December and January the weather is cold. Moreover other
natural possessions, nature has talented the region by vast water resources in the form
of rivers, streams, lakes, springs, and underground water. These possessions of water
are adequate for meeting necessities of irrigation and drinking. For the irrigation
purposes a number of canals have been constructed from these water resources in the
district.
3.4.4 Population
Haripur has a population of 0.692 according to the 1998 census report in which only
12 percent people lives in town areas, while, the rest of the population lives in the
rural areas.
3.4.5 Construction materials
Baked bricks, cemented blocks and shaped stones are the main construction
substances exploited in the structure of the boundary walls, in most in the urban area
and least in the rural area. In the rural area the mud made walls and houses are also
found in large quantities. Table 3.5 illustrates the information of the structure matter
utilized in the outer wall of the housing units and the Table 3.6 illustrates the
information of the structure matter utilized in the roofs of the housing units.
31
Table 3.5: Construction materials used in the outer walls (%) of the Haripur district.
Walls materials All area Rural Urban Baked bricks/Blocks/Stones 79.2 68.3 90.2 Un-baked/bricks/Earth bounded 18.4 27.7 9.1 Wood/Bamboo 1.6 3.1 0.4 Others 0.8 0.9 0.3
Table 3.6: Construction materials used in roofs (%) of the Haripur district.
Roof materials All area Rural Urban RCC/RCB 48.2 18.3 78.1 Cement/Iron sheet 11.2 6.4 16.0 Wood/Bamboo 38.7 73.5 4.1 Others 2.1 1.8 0.8
3.5 Battgram
The district Battgram lies between 72.15º to 73.35º east longitudes and 34.20º to 34.60º
north latitudes with height 600 m above the sea level. This district has two tehsils
Battgram itself and Allyee tehsil. The district is surrounded by Kohistan district in the
north, Shangla district in the west north, Mansehra district in south east. Total area of
the district is 1301 square kilometer. The large part of the people speaks Pushto
language (98%). However other languages such as Kohistani, Gojjri and Balti are also
spoken in the some part of the area.
Large part of the area earn their living hoods from the agriculture but
significant number of people also having government job as well as working in the
other part of the country and outside the country. The area has lower literacy rate and
lacks basic facilities such as health and social awareness. The October 2005 earth
quake severely affected this area and most of the infrastructures destroyed along with
the lost of valuable lives of people.
3.5.1 Physical features and topography
Battgram is the major city of Battgram district in the Khyber Pakhtun Khwa. It is sited
205 km north of Islamabad and 260 km from Peshawar. The city is situated in the
north part of the Hazara Division which is known for its pleasant weather and for the
tourism. It serves as a gate for Kohistan the northern part of the Pakistan.
32
3.5.2 Geology
The bulk of district Battgram consists of Mansehra Granite and Tanawal Formation of
Ordovician to Devonian age. In the northeastern part of the district, Tanawal
Formation, has been thrusted over Salkhala Formation along Balakot Fault. In the
northern part Kingriali and Panjal formations has been thrusted over Tanawal
Formation along Banna Fault. Further northward the Kingriali and Panjal formations
are thrusted over by Kamila amphibolites and Jijal/Sapat granulites along Main
Mantle Thrust (MMT). The MMT is marked by Kishora Melange zone rocks bounded
in the north by Kohistan Fault and in the south by Kishora Fault. In the northwestern
part of district Battgram the Kishora Melange zone rocks are thrusted over lower
Proterozoic Kotla and Reshian granites, and Besham Granites of lower Paleozoic age
[147-149]. Gravel and associated sand occurs in the bed of the Allyee River and its
tributaries near Allyee and Banan.
3.5.3 Climate
The summer season is hot which usually starts from May and ended in September. In
the month of June the temperature reach up to 41.5 ºC. The temperature drops rapidly
from October onward. December and January are the coldest months in which
temperature fall below freezing point in the hilly areas. Owing to thorough cultivation
and artificial irrigation, the area is humid. July, August, December and January are the
rainy months for the area. A little rain falls in the remaining months of the year. The
comparative dampness is fairly high all over the year, yet the month of December has
the maximum humidity of 63.35%.
3.5.4 Population
The people of the district according to 1998 survey details was 0.5 million. The
literacy rate in the area is very low and has lack of basic facilities such as health and
social awareness. The October 2005 earth quake severely affected this area and most
of the infrastructures destroyed along with the lost of valuable lives of people.
3.5.5 Construction materials
As the district consists most of the area rural where the mud made walls and houses
are common. Beside the mud made houses and walls, the wood, baked bricks,
33
cemented blocks and shaped stones made houses and wall are also common in the
area. However it found little in the rural and most in the urban area. The details of the
construction material used in the housing units are given in Table 3.7 & 3.8.
Table 3.7: Construction materials used in the outer walls (%) of the Battgram district.
Walls materials All area Rural Urban Baked bricks/Blocks/Stones 58.3 32.5 84.1 Un-baked/bricks/Earth bounded 24.6 34.4 14.8 Wood/Bamboo 14.2 27.6 0.8 Others 2.9 5.5 0.3
Table 3.8: Construction materials used in roofs (%) of the Battgram district.
Roof materials All area Rural Urban RCC/RCB 41.5 14.1 68.9 Cement/Iron sheet 10.8 4.2 17.4 Wood/Bamboo 44.6 76.3 12.9 Others 3.1 5.4 0.8
3.6 Kohistan
Kohistan lies between 74.0º to 74.9º E longitude and 34.5º to 35.1º N latitude. Kohistan
district is an administrative district of N.W.F.P (Khyber Pakhtunkhwa), an area of
7,492 square kilometer. District Kohistan borders district Swat in the west, district
Shangla southwest and district Batagram in south, district Mansehra in northeast,
district Diamir in northwest, district Astore in the north, district Skardu in the
northeast and Azad Kashmir in the east. Kohistan district is divided into three sub
divisions that are Palas, Pattan and Dassu. The capital of Kohistan district is Dassu.
3.6.1 Physical features and topography
Kohistan is the gate way to Northern part, Gilgit-Baltistan, Pakistan. Kohistan is place
where three mountain system meet these are Hindukush, Karakuram and Himalaya
and serve as a natural frontier for environmental areas in the shackles of the
Himalayas, Karakoram and Hindu Kush mountains.
3.6.2 Geology
Kohistan means the land of mountains. One can hardly found plain area in Kohistan.
It could be properly explained as all mountains with no land. The Indus River flows
through the centre of Kohistan from begin to end and separate it into two parts -
34
Hazara Kohistan and Swat Kohistan. This then combined in 1976 to form Kohistan
district.
The Kotla and Reshian granites of lower Proterozoic age and Besham Granites
of lower Paleozoic age outcrop in the southwestern part of district Kohistan. These
rocks have a faulted contact with Kishora Melange Zone rocks and Jijal/Sapat
ultramafic rocks in the south western part of the district Kohistan along Kohistan and
Kishora faults. Main Mantle Thrust passes in the southern part of district Kohistan.
The dominant rocks in southern Kohistan are the Kamila Amphibolites with
subordinate Jijal ultramafics and Jijal/Sapat granulites. The northern and northwestern
parts of district Kohistan contain Chilas gabbronorites and Kohistan batholith rocks
[147, 148].
3.6.3 Climate
The climate of the district has a tendency to be moderately soft. The district receive
rain and snow fall in winter, so the winter is cold and the summer somewhat hot.
Kohistan has mountains and the agricultural regions are found on the hills. Those
areas in Kohistan lie at altitude below 900m have very hot summer and very cold
winter. Pleasant weather is found in summer in the higher areas. Owing to the
concentrated snowfall, subsequently the people of the area restricted inside to their
homes in winter.
3.6.4 Population
From 1998 census report the population of Kohistan district was 0.473 millions.
3.6.5 Construction materials
As the district consists most of the area rural where the mud made walls and houses
are common beside the mud made houses major portion of the houses are also wood
however baked bricks, cemented blocks and shaped stones are the main construction
materials used in the construction of the outer walls in most in the town region and
least in the rural region. The information of the structure matter utilized the housing
units in the outer walls and roofs are shown in Table 3.9 & 3.10 respectively.
35
Table 3.9: Construction materials used in the outer walls (%) of the Kohistan district.
Walls materials All area Rural Urban Baked bricks/Blocks/Stones 58.3 32.5 84.1 Un-baked/bricks/Earth bounded 24.6 34.4 14.8 Wood/Bamboo 14.2 27.6 0.8 Others 2.9 5.5 0.3
Table 3.10: Construction materials used in roofs (%) of the Kohistan district.
Roof materials All area Rural Urban RCC/RCB 41.5 14.1 68.9 Cement/Iron sheet 10.8 4.2 17.4 Wood/Bamboo 44.6 76.3 12.9 Others 3.1 5.4 0.8
The estimated population of the Hazara in 2010 is around 5 million. The
estimated statistics is revealed in Table 3.11.
Table 3.11: Estimated statistics of Hazara Division in 2010*.
District Area (km2) Population (Millions) Abbottabad 1802 1.15 Mansehra 5957 1.6 Haripur 1763 0.82 Battgram 1310 0.6 Kohistan 7581 0.71
*Since there is no official (state) census survey after 1998 till June, 2011.
36
CHAPTER 4
MEASUREMENT TECHNIQUES
The radon measurement technique is selected on the basis of whether to measure
radon itself or its daughter products. In both cases, α and γ radio activities are
measurables, that can be measured separately or at the same time. However few of the
daughters, β radioactivity can also be measured. One of the following techniques can
be used for detection and thereby for measurement.
Nuclear emulsion
Adsorption
Solid scintillation
Gamma spectroscopy
Beta monitoring
Solid state nuclear track detector
Electrometer or electroscope
Ionization chamber
Surface barrier detectors
Thermo luminiscent phosphors
Electrets
The measurement of radon can be done either in the laboratory or in the field.
Nearly all the methods that are exercised in the field measurement can be used in the
laboratory, yet some techniques are such that are not common in the field
measurement rather they are used in the laboratory.
In the laboratory one relies essentially on common techniques for the
determination of radioactivity and counting. The major distinction is the adaptation of
these techniques to the gaseous nature of radon.
Scintillation counting in the gaseous stage has been mostly used for the
reason(gaseous nature of radon). Lucas was perhaps the earliest one to publish
something concerning it. It is one of the oldest and most dependable method [154]. In
this method the apparatus is a glass vessel coated inside with scintillation substance
such as ZnS or barium cynide called phosphor. Once the alpha particle hits the
37
phosphor it produces tiny light flashes which are further amplified by photomultiplier.
Some time it is replaced by micro channel plates.
Sensitivity depends primarily on the duration of the counting period. It gets better
somewhat by raising the capacity of the container. A sensitivity of a few 3mBq can
be attained. It can be extra amplified by electrically collecting 218Po atoms straight on
the detector [155]. A more advanced edition of the Lucas cell is the multiple
scintillation chamber apparatus which offers, as a function of time, an superior quality
respond [156].
Scintillation counting can also be performed for radon level estimation in the
liquid phase, once it has been pulled out. One fine example of radon removal by
solvent is the case of radon measurement in the ground water. Radon can be extracted
from water by mixing it with toluene. The quantity of radon enclosed in the toluene is
measured via liquid scintillation, whichever using the toluene itself as the scintillating
liquid or by adding known amounts of liquid scintillator such as PPO and POPOP
[157, 158].
Ionization chambers [159] and proportional counters [160] are the main
extensively applied radiation measurement methods functional to radon determination
by means of sampling it from the environment. Spectroscopy can, in general, be used
for indirect radon determination. In all these cases, radon progenies are the emitting
material, in which α spectroscopy is very common.
Radon measurement in situ requires detector to be put in place and left for
ample duration of time. A measurement can be nonstop (continuous) or distinct. It can
be passive or active depending upon the sampling whether these are taken in the
natural way or forced to enter in the detection instrument. So keeping this in view the
detector can be mainly classified in to two types (i) passive (ii) active . Some major
passive and active techniques are discussed as below:
4.1 Passive Techniques
To get results which comprise the seasonal, climate and ecological conditions on the
radon concentrations in the dwellings, it is imperative to take measurements over a
lengthy phase of time. It is the long term average in dwellings that determines the
damage to human's health. For this purpose the integrated devices are used. Hence
38
these techniques are also used beside the active technique in the present work in order
to find out the annual mean radon concentration at a fix point.
4.1.1 Charcoal canister technique
This technique is utilized in the survey where quick radon measurement is needed.
The radon is adsorbed and retained through activated charcoal. A canister contains
activated charcoal uncovered to the air for few days, so that radon enters in the
canister (see Fig.4.1). The quantity of radioactive substance collected in the activated
charcoal is calculated by gamma spectroscopy or by liquid scintillation counting. The
first problem with this technique is that it needs a classy electronics for analysis and
secondly the results cannot be reproduced even in the same site for the similar
experimental situation.
4.1.2 Electrets
These detectors, containing an electro-statically charged Teflon disk, are extensively
used for long-term measurements. Decay products strike the Teflon desk which
causes the decrease in its surface voltage. The decrease in the voltage gives the
measurement of the radon concentration.
4.1.3 Thermo luminiscent technique
Thermo luminiscent is the property of the substance whereby it can proficient of
energy that can be released in the form of light when it is heated. These materials are
called Thermo Luminescent Detector (TLD) chips. TLDs are sensitive to alpha, beta
and gamma radiation for this a method is adapted to determine the alpha contribution
only. Two TLDs are mounted in an inverted cup and placed in the ground. One of the
TLDs is wrapped in the foil that will keep out all of the alpha particles that it must be
made radon tight, but the beta and gamma radiations are not excluded. After a certain
time the TLDs are retrieved and analyzed by heating up to 300 ºC in the suitable read
out equipment. When a chip is heated, a light is emitted, which is comparative to the
amount of radiation present. The part from alpha radiation can be determined by
subtracting the intensity of the energy in first TLD (exposed to only beta radiation)
from second TLD (exposed to Alpha, Beta and Gamma radiation) and hence the radon
activity is measured [161].
39
4.1.4 Etched Track Detectors
All the above stated passive techniques require extensive electronics and sophisticated
laboratory amenities. This makes it inappropriate for use in the far-flung and rugged
areas. Besides this, the instruments used, in all the above passive techniques are
expensive and not easily available [5]. The most extensively used method for long
monitoring period is based on materials known as Solid State Nuclear Track Detector
( SSNTDs ) or etched-track detectors. The technique is simple to use and
comparatively economical. In this regard several materials have been developed; the
most suitable for indoor radon measurements appears to be 39CR since of its good
sensitivity, steadiness against environment factors and high level of visual clearness
[162]. So in present study the SSNTDs -based method was used for the indoor radon
measurement while one of the active techniques was used for the measurement of
radon in water and soil gas. Their detail study will be discussed in the later chapter.
To detect the radon gas alone in a given environment, the instrument should
have mechanism to detach the radon gas from its particulate daughter products and to
permit just radon to enter into the sensitive volume of the detector. For this, several
configurations have been developed which used etched track detectors to measure
indoor radon. Few of them are discussed below.
4.1.4.1 Membrane Permeation Samplers
The dosimeter schematically is shown in Fig. 4.2a. Here the permeable filter closes
the open end of the cup [2]. The enclosure eliminates the emitters, and the filter
area and thickness are planned to excluded unnecessary Rn219 ( 2/1 = 3.96s) and
Rn220 ( 2/1 = 55.6s) without particularly diminishing Rn222 ( 2/1 = 3.82d), beside with
the daughters that are formed following the 222Rn goes into the detection space. The
filter is made of a permeable material for instance fiber glass, micro porous paper or a
plastic such as polyethylene (10µm thick).
4.1.4.2 Plastic bag permeation samplers
The infiltration sampler is shown in Fig. 4.2b. This infiltration samplers made from a
heat-sealed plastic bag (filter) prepared of polyethylene. There are two
39CR detector foils and aluminized polycarbonate degraders face the detector foils
to optimize the detector responses and to make their surface conductive. The
40
polyethylene bag protects the detector from humidity, dust, thoron and radon
daughters [6]7. The advantages of such type of dosimeter are: (i) easy heat sealing
and therefore small expenditure,(ii) undersized dimension and quick sampling
time,(iii) high radon permeability and (iv) removal of water vapors. Besides, the
majority of the radon dosimeters have a rejoinder which depends on the atmospheric
pressure, as sensitive volume depends on the range of particles, which varies with
pressure. On the contrary, the plastic bag sampler with polycarbonate degraders has
little reliance on the atmospheric pressure, since the degrader is not the air but the
plastic foil.
4.1.4.3 NRPB radon dosimeter
The NRPB radon dosimeter, designed by the National Radiological Protection Board
of UK with current name Radiation Protection Division )(HPA is shown in Fig. 4.2c.
It has two polypropylene parts: a circular base with an alcove to keep the detection
element in place and a vaulted circular upper section with an inner circular base-
retaining swagger. The detector component uses a section of 39CR plastic that
registers the alpha particle tracks from the decays of radon and its progenies products
in an enclosed volume. The overall size of the assembled dosimeter are; a diameter of
about 6 cm and an utmost depth of 2 cm the two parts fit fairly tight in order to
eliminate dampness and radon progenies. Radon enters through a petite opening
between the two halves. It is a passive radon detector to measure the time
incorporated radon gas concentration in the mediate environment of the detector
[163].
The same detector and dosimeter was used for indoor radon levels in the present
survey.
4.2 Active techniques
Active techniques are those in which electronic detectors are used to take the data on-
line. Such techniques are used for a short term measurements. The active techniques
are based upon methods in which grab sample of the air (in case of indoor radon) is
collected at a moment of time, followed by measurement of radon concentration
through its α-particle activity. Following are the some active techniques:
41
4.2.1 Lucas cell (scintillation method)
One of the oldest techniques is the Lucas Cell; it consists of glass pot coated inside
with scintillating material such as ZnS, apart from the bottom end surface, which is
transparent and attached to a photomultiplier tube PMT . It is typically of cylindrical
form but can be of any shape depending on the type of PMT in use to count the
scintillation produced. Since α can travels only short distances in air before stopping,
the volumetric capacity of the Lucas cell is up to a few hundred cubic centimeters. A
sample of air is exhausted into the cell, and the α- particles produced from radon
decay cause scintillations in ZnS, detected by the photomultiplier tube and generate
the electric pulse.[refence]
4.2.2 Ionization Chamber
The ionization chamber is filled with filtered radon. The α-particle emitted in the
decay of radon and its progenies ionizes the air in the chamber. The electrons and ions
are drifted towards the electrodes in the presence of the voltage applied. The resulting
current is a measure of the quantity of decayed radon atoms. Counting is made after
the equilibrium recognized between the radon and its progenies and the radon
concentration can be taken from the number of the pulses. [refence]
4.2.3 Surface Barrier Detector (SBD)
It is the p-n junction diode operated under the reversed biased setting. The α-particles
from radon decay enters the depletion region and creates electron hole pairs, both
move in the opposite directions and total number of electrons collected can form an
electronic pulse whose amplitude is comparative to the energy of the radiation.
4.2.4 Two filter method
This technique measures both radon and its progenies. Through first filter air is passed
so that radon progenies are detached, and allow the air to pass through a long decay
chamber so that the progenies are produced again and collected on the second filter.
The filters are counted independently; from the first filter the radon progenies
concentration and from the second filter the radon concentration are determined.
42
4.2.5 Working level method
Air is pumped through a filter for a particular time. Alpha particles emitted from
radon progenies deposited on the filter are counted using surface barrier (SB).
Mensura Working Level Meter is the modern gadget used for this purpose. This
operates by sampling air from the environment at a continuous rate. It is operated by
portable battery.
The active measurement techniques are not so useful for accurately
measurement the radon levels because of temporal variation in radon level due to the
temperature and pressure gradients. But active techniques become more important for
the large sampling and to cover more area in short period of time. To make this
method more advantageous over passive techniques, a regularly monitoring is
required of the radon concentration in water or in air or even in the soil. Usually radon
measurements, especially in inaccessible zones, are done through SSNTDs , but these
can give only integrated results and they need a frequent substitution to read the
tracks. We preferred an active device (RAD7) for sampling of soil gas into the
detecting instrument. The option of an active detection allowed radon monitoring for
short time periods and both short and long term analysis [164].
Both active and passive techniques are used in the present survey. For radon in
water and soil gas, active technique was used while for radon concentrations in
dwelling passive technique ( SSNTDs ) which consists of 39CR , was used. Radon in
water were measured by number of ways through active techniques, using Gamma
Spectroscopy (GS ), Lucas Cell ( LC ) and Liquid Scintillation ( LS ).
Gamma spectroscopy measures the gamma rays emitted from radon's decay
progenies from the closed container of containing radon water. In this method it is
possible to measure low value radioactivity which is still considered to be significant.
The Lucas Cell method has been in use for decades for laboratory study
of Rn222 and Ra226 (by means of radon emanation). This method tends to some extent
effort concentrated, using an intricate structure of glassware and a vacuum drive to
empty a Lucas Cell, and refilling it from the radon in water sample. The cell then
counted by standard technique. An expert technician can produce correct, repeatable
measurements at fairly low concentrations using this method.
The Liquid Scintillation technique has been used since 1970. A liquid
scintillation cocktail is mixed to the sample in a 25mL glass LS vial which extracts the
43
radon from water, consequently that decays α particle and scintillate the cocktail. The
technique uses normal LS counters, which are extremely mechanized and can count
more than a few hundred samples in series with no disturbance. The EPA has accepted
that the LS technique is as correct and sensitive as the LC technique, although less
effort demanding, and inexpensive.
In contrast with the stated techniques, the 7RAD offers a technique as correct
as LS however quicker to the first reading, moveable, still less labor demanding and
less costly. It also abolishes the requirement for harmful chemicals. The large part of
the present study was carried out using the 7RAD besides using the passive technique
such as 39CR . For indoor radon concentrations passive technique was used while
for soil radon gas concentrations and for water radon concentrations active technique
of 7RAD was used. Fig. 4.4 and 4.5 show the schematic and true picture
of 7RAD respectively. The working of the 7RAD for radon levels in the water, soil
and air will be discussed in the coming chapters in detail.
Fig.4.1: The charcoal canister
44
Fig.4.2: Radon monitoring devices based on etched track detectors (a) filter permeation sampler (b) plastic bag permeation sampler (c) NRBP radon dosimeter
RADON CONCENTRATION
Fig.4.3: Diagram illustration of the key procedure involved in radon recognition and assessment by means of an etched trail radon dosimeter [7]
Exposure Latent track Visualization Visible Evaluation Track
45
Fig.4.4: Schematic of 7RAD
Fig. 4.5: 7RAD
46
CHAPTER 5
EXPERIMENTAL
5.1 Radon Level in Water
Radon gas is formed when Uranium decays to Radium and which then decays to
radon. Uranium is found in minute quantity in most rocks, soil and groundwater.
Measurement of radon in natural water such as lake, spring, well and groundwater
provides useful information about the Uranium deposits and also helps in exploring
hidden geological faults. To protect public from harmful radiation hazards of radon
and to determine seismic related changes in the radon content of water, constant
supervision of radioactivity in drinking, mineral and thermal waters is necessary [55,
88].
The distressed earthquake of October 8, 2005 in Pakistan resulted in vast loss
of valuable lives and belongings. It is usually believed that the level of radon
concentration in an area increases considerably[refence] before a predictable earth-
quake to happen. It is therefore, necessary to monitor and asses the concentration
levels of radon in the earth-quake hit areas of North West Frontier Province
{N.W.F.P.(Khyber Pakhtunkhwa)} Pakistan in the post earth-quake scenario.
5.1.1 Sampling
A total 279 water samples were collected from various sites of the districts Haripur,
Abbottabad, Mansehra, Battgram, Kohistan and from their surrounding, and from
Balakot as a special case as it lies on the fault line. These sites are located not very
far-flung from each other and lying in a radius of about 10 to 20 kilometers the
sources of drinking water to the community of these localities are definitely different.
Numbers of samples from surface, borehole and spring water were 114, 93 and 72,
respectively.
A total 54 water samples were collected from Abbottabad district, which
incorporate 20, 19 and 15 of surface, borehole and spring water respectively. All the
surface water samples were collected from nallah Harno at different points (S.No. 1 to
20) in Table 6.6. Out of 19 borehole water samples, 3 from Mandian (S.No. 4 ,5 &6 in
Table 6.6), six from city (No. 1,2,3,7,8 & 20) in Table 6.6, four from Nawan sher
47
(S.No. 10,12,13 & 18) in Table 6.6, 2 from Jhangi Khoja (S.No. 14 &15) in Table 6.6
and the remaining four from Qalander Abad (S.No. 11,16, 17, 19) in Table 6.6
regions, were collected. These samples were taken at different site from these areas.
Four spring water samples out of 15 from Tandyani (S.No. 1, 2,3 & 4) in Table 6.5 ,
five from Tandachoha (S.No. 8, 9, 11,12 &14) in Table 6.5, three each from Ilyasi
(S.No. 10, 13 &15) in Table 6.5 and Kakul (S.No. 5, 6 &7) in Table 6.5 regions, were
collected, from different points.
From Mansehra total 47 samples were obtained including, 24 and 23 of
surface and borehole water respectively. Out of 24 surface water samples 14 from the
river Siren (S.No. 1, 3, 5, 6, 7, 8, 10, 19, 20, 21, 23, 22, 24 &25) in Table 6.6 and the
remaining 10 from the Chata Bata nullah (S.No. 2, 4, 11, 12, 13, 14, 15, 16, 17 & 18)
in Table 6.6 regions, were collected, from different points. In the 23 borehole water
samples, 3 each from Dab#1(1, 2, & 3) in Table 6.6, Dab#2 (S.No. 4, 5,&6) in Table
6.6, and Jabri (S.No. 7, 8 & 9) in Table 6.6, 4 from Lari Ada (S.No. 10, 11, 12 &13)
in Table 6.6, 5 from city (14, 15, 16, 17 &18) in Table 6.6, 2 from Attar shesha (S.No.
20 & 22) in Table 6.6 and 3 from Batrasi (S.No. 23, 24 &25) in Table 6.6 regions,
were collected, from different sites.
From Haripur, 59 samples were collected which comprise of 14, 30 and 15 of
surface, borehole and spring water respectively. Out of 14 surface water samples, 6
samples from Sari saleh (S.No. 1, 3, 5, 6, 9 & 12) in Table 6.6 and 8 from Khan pur
(S.No. 13, 16, 17, 18, 22, 23, 26 & 28) in Table 6.6 regions, were collected, from
different sites. In 30 borehole water samples, 3 each from sari Saleh (S.No. 1, 2 &3)
in Table 6.6, Ali Khan (S.No. 4, 5 & 6) in Table 6.6, and Shah Maqsuad (S.No. 7, 8 &
9) in Table 6.6, 6 from city (S.No. 10, 11, 12, 13, 14 &15) in Table 6.6, 4 from
Malikyar (S.No. 16, 17, 18 & 19) in Table 6.6, 5 from Kot Najeeb ullah (S.No.20, 21,
22, 23 & 24) in Table 6.6, 4 from Hattar (S.No. 25, 26, 27 & 28) in Table 6.6 and 2
from Sari Kot (S.No. 29 & 30) in Table 6.6 regions, were collected, from different
points. Out of 15 spring water samples, 2 from Chupra (S.No. 1& 2) in Table 6.5, 2
Chajian (S.No.3 & 4) in Table 6.5, 3 from Jabba (S.No. 5, 6 &7) in Table 6.5, 2 from
Kunara (S.No. 8 & 9) in Table 6.5, 3 from Kuhala (S.No. 10, 11 & 12) in Table 6.5, 2
from Najaf Pur (S.No. 13 & 14) in Table 6.5 and 1 from Bagra (S.No. 15) in Table 6.5
regions, were collected, from different points.
From Battgram, 45 samples were collected which comprise of 11, 19 and 15
of surface, borehole and spring water respectively. The surface water samples were
48
collected from the Allaie Khwar from different points in Allayee region (S.No. 1, 5, 8,
9, 11, 14, 15, 19, 22, 25 & 27) in Table 6.7. Out of 19 borehole water samples, 5 each
from city (S.No. 1, 2, 3, 4 &5) in Table 6.7 and surrounding to city (S.No. 6, 8, 9, 10,
& 12) in Table 6.7, 5 from Thakot (S.No. 14, 17, 18, 20, & 23) in Table 6.7 and 4
from Allyee (S.No. 15, 24, 25 & 28) in Table 6.7 regions, were collected, from
different points. In the15 spring water samples, 8 from Ajmera (S.No. 1, 2, 3, 4, 5, 6,
7 & 8) in Table 6.5, 7 from Allyee (S.No. 9, 10, 11, 12,13, 14 &15) in Table 6.5
regions, were collected, from different points.
From Kohistan district, a total 39 samples were collected which consist of 13,
11 and 15 of surface, borehole and spring water respectively. Surface water samples
were collected from the river Indus, flows across the Kohistan area. These samples
were collected from at different points, of course the source was the same. Out of 11
borehole water samples, 5 from Patan (S.No. 1, 5, 9, 26 &29) in the Table 6.7, 6 from
Dassu (S.No. 12, 15, 16, 19, 21 & 24) in the Table 6.7 regions, were collected, from
different points. These points were within the radius of 10 to 20 Km. In the 15 spring
water samples, 5 each from Dassu (S.No. 1, 2, 3, 4 &5) in the Table 6.5, Palas (S.No.
6, 7, 8, 9 & 10) in the Table 6.5 and Patan (S.No. 11, 12, 13, 14 & 15) in the Table 6.5
regions, were collected, from different points within the radius of 20 km.
From Balakot, 35 samples were collected which include 11, 12 and 12 samples
of surface, borehole and spring water respectively. Surface water samples were
collected from the river Kunihar at different points such as at Balakot (S.No. 1, 3, 5 &
6) in Table 6.7, Bisian upper (S.No. 9 & 11) in Table 6.7, Bisian Lower (S.No. 13 &
14) in Table 6.7 and from Gari Habib ullah (S.No. 16, 19 & 23) in Table 6.7. In the 12
borehole water samples four each from city (S.No. 1, 3, 5 & 8) as given in Table 6.7,
Met office and its surrounding (S.No. 10, 11, 14 & 18) in Table 6.7 and Garlat (S.No.
21, 24, 25 & 28) in Table 6.7 regions, were collected, from different points.
Twelve spring water samples were collected from Balakot from near the fault
line at different longitude (S.No. 1, 3-9, 11, 13, 14 &15) in Table 6.5. These points
were lying in the dimension of 16 km × 10 km (160 km2 area).
Most of this area (Abbottabad, Mansehra and Battgram) was severally affected
in October 2005 earthquake. The bore/well water samples were obtained with the help
of a tube, attached to the faucet in a controlled flow rate, while the surface and spring
water samples were directly collected in the 500 ml glass bottles, filled and caped
inside the respective sources so that to stop the entrance of outside air into the bottles.
49
A number of duplicates samples were also taken from random sites for checking the
stability and robustness of the method. Acidification of all water samples was carried
out by adding concentrated 3HNO ( 1lml of sample water) for the preservation and
were then transferred to the laboratory for the measurement and investigation. These
samples were collected for a period of one year from August (2009) to July (2010),
during which temperature remained in the range of 15 to 30 ºC.
As radon concentration in water can be either measured by active or passive
technique. The passive techniques include many, in which solid state nuclear track
detector (SSNTD) is widely used due to its advantages over others mentioned earlier.
Similarly there are many active techniques for radon concentration measurement in
water. Although SSNTD has some advantages but installation, collecting, etching and
analyzing its sample take long time, which makes this type of detector unsuitable for
the large number of samples and quick measurements. The present studies were
carried out using active techniques with the help of two types of devices available in
the laboratory, they are, (a) The Pylon WG-1001 Radon System (b) 7RAD Electronic
radon Detector; the measurement technique of each is explained as follows;
For accurate measurement of radon concentration, using the Lucas cell, by
counting particles emitted from radon and its progenies ( BiandPbPo 214214218 , ), a
time wait of 4 hours is essential so that the radioactive equilibrium between radon and
its progenies achieved. The Lucas cell was placed for 4 h before particles were
counted by the a-scintillation counter (Pylon counter). Therefore the total time for one
sample from preparing to count of a particle was approximately 5 hrs. The time of
counting ( CT ) was noted. The radon concentration is measured, by means of the
following equation [165] :
VSDF
BCA
66.6
100)( (5.1)
where A is Rn222 activity in pico-Curie per liter( 1lpCi ), C is the gross count rate
in ,CPM B is the background count rate in ,CPM F is the cell counting efficiency
(0.745 DPMCPM / ), 6.66 is the product of the number of α-emitters (3) and the
conversion factor for DPM DPM to 1lpCi (2.22), D is the degassing efficiency for
300A cells (0.9), S is the correction for the decay of radon from sampling time ST to
50
counting time CT (0.97026)s and V is the sample volume (190 ml). The radon
concentration thus obtained in 1lpCi was converted to 3mBq (1 1lpCi =
37 3mBq ).The background radiation was measured in a scintillation cell (Lucas cell)
for three 5-min intervals and the average was taken in CPM . Before taking each new
sample, flushing of the degassing unit’ and the Lucas cell was done. A sample of
water of 190 ml was taken in the sample graduated tube of the Degassing unit. The air
was sucked through the bubbler inlet, water trap, Drierite tube and exhaust tube to the
Lucas cell by the air pump to a pressure of 68.58 cm of Mercury. The process took 5–
6 min in preparing a sample in the Lucas cell. The time of sampling ( ST ) was noted.
For counting, the cell was placed in a radiation monitor 4 hours after sampling so that
the radon activity in the cell reaches equilibrium with its progenies. After the decay of
fluorescence, the cell was counted for three 5-min time intervals in a Pylon counter. In
this way the analyzing time for one was approximately 5hrs.
7RAD Electronic Radon Detector (Durridge Co.) is a solid state α detector as
shown in Fig. 3.4. A solid state detector is a semiconductor material (usually Silicon)
that converts alpha radiation directly to an electrical signal. The internal sample cell
of 7RAD is a 0.7 litre hemisphere, layered on the inside with an electrical conductor.
A solid state, ion entrenched, planar Silicon alpha detector is at the centre of the
hemisphere. The high voltage power circuit charges the inside conductor to a potential
of 2000-2500 volts relative to the detector, creating an electric field throughout the
volume of the cell. The electric field pushes the positive charges onto the detector.
The 7RAD detector calculates the concentration in water sample by
multiplying the air loop concentration by a preset conversion coefficient. This
conversion coefficient has been resulted from the volume of the air loop, the volume
of the sample and the equilibrium radon distribution coefficient at room temperature.
For 250 ml volume of water sample, the conversion coefficient is about 4.
In some cases where in-situ measurements of water samples were not possible,
and the measurements were made after 10 hours of the collection of samples, the
measurements were corrected for the decay time by employing a decay correction
factor ( DCF ) in the measured values, using the equation[165]:
( )132.4
T
DCF e (5.2)
Where T is the decay time in hours and 132.4 is the mean life of Rn222 .
51
A Rn222 nucleus that decays within the cell leaves its transformed
nucleus, Po218 as a positively charged. The electric field within the cell drives this
positively charged ion to the detector to which it sticks. When Po218 decays upon the
active surface of the detector, its alpha particle has a 50% probability of entering the
detector and producing an electrical signal proportional in strength of the energy of
alpha particle. Following decays of the same nucleus produce beta particles which are
not detected here or alpha particles of different energies (other than 6MeV, 7.69MeV)
. Different isotopes of polonium have different alpha energies and produce different
strength signals in the detector which are then displayed in different windows. After
about 30 minutes, the average radon content is determined from the activity of Po218
without bringing the radon in the samples to equilibrium with its daughters. This
technique enables one to take more samples analyzed in less time and thus covering
vast area for the survey purpose in a specified time. The sensitivity of the instrument
is 0.508 and 0.247 1( lpCiCPM ) in normal and sniff modes respectively. The
dynamic range of the instrument is 0.1-10,000 1lpCi .
7RAD is designed to detect alpha particles only, so focus will be on the alpha
particles in this type of detector. When a radon nucleus decays, it releases an alpha
particle with 5.49 Mev of energy, and the nucleus transforms to 218Po . Polonium
atoms are metals and tend to stick to surfaces they come in contact with, e.g., a dust
particle in the air, or a wall, or the inside of lung. Like radon, 218Po emits an alpha
particle when it decay, but with an energy of 6.00 Mev rather than 5.49 Mev with a
half life of 3.05 minutes. After a few decays the polonium-218 becomes polonium-
214 and it emits alpha energy of 7.69 Mev with a half life of 0.000164 seconds. Due
to long half life of 210Pb it is ignored in the radon measurement, though it affects the
background of some instruments but not of 7RAD . Also the alpha from 210Po creates
unwanted background for the other type of instruments but not for the 7RAD .
Similarly radon-222, every radon -220 (thoron) nucleus decays to 208Pb through a
sequence of 5 transformations. 7RAD uses a solid state alpha detector. It is a
semiconductor material (usually silicon) that converts alpha radiation directly to an
electrical signal. The energy of the alpha particles are determine electronically which
tells, which isotope of polonium produced the radiation so that it can be distinguish
between old and new radon , radon from thoron and signal from noise.
52
Measurements of both active devices (a) Pylon counter (b) 7RAD α detector
were within the deviation of the measurement. However 7RAD measurement has
advantage over Pylon counter as the first one can perform the in situ measurements
(which were essential in the present case) and the time taken for radon measurement
from a sample was less than, a second. Therefore the measurements given in the
present work were made on 7RAD .
5.2 Soil gas radon
For soil gas radon concentrations, study was carried out in the Hazara Division. The
soil gas samples were collected in all five districts of the Division. In case of
Mansehra district, the samples were taken from Balakot beside the Balakot-Bagh (B-
B) fault line.
5.2.1 Sampling
A total 67 soil gas samples were composed from different sites of the study area for
one year of period from August (2009) to July (2010), during which temperature
remained above 10 ºC and in the range of 15 ºC to 30 ºC.
From Abbottabad a total of 14 soil gas samples were taken. Out of these 14
soil gas samples, 3 samples from Mandian (S.No. 1, 2 & 3) in Table 6.11, 4 from city
(S.No. 4, 5,6 & 7) in Table 6.6, 5 from Nawansher (S.No. 8, 9, 10, 11 & 12) in Table
6.11 and 2 from Kakul (S.No. 13 &14) in Table 6.11 regions were collected from
different points. These sites were within the radius of 10 to 20 km.
A total of 14 soil gas samples were taken from district Haripur. In these
samples 4 from Sarisalh (S.No. 1, 2,3 & 4) in Table 6.11, 5 from city (S.No. 5, 6, 7,8
& 9) in Table 6.11, 3 from Kot Najeeb Ullah (S.No. 10,11 & 12) in Table 6.11 and 2
from Hattar (S.No. 13 & 14) in Table 6.11 regions were collected from different
points, the sites of sampling were within the radius of 20 km.
From Battgram 14 soil gas samples were taken. Out of these samples, 5 each
from main city (S.No. 1, 2, 3,4 & 5) in Table 6.11 and Allyee (S.No. 6, 7, 8,9 & 10) in
Table 6.11 and 4 from Thakot (S.No. 11 12,13 & 14) in Table 6.11 regions were
collected from different points. These sites of sampling within the radius of 15 km.
From Kohistan district 14 soil gas samples were taken. which incorporate 5
each from Palas (S.No. 1, 2, 3,4 & 5) in Table 6.11 and Dassu (S.No. 6, 7, 8,9 & 10)
53
in Table 6.11 and 4 from Patan (S.No. 11, 12,13 & 14) in Table 6.11 regions were
collected from different points.
From Balakot 11 soil gas samples were collected near the fault line at different
longitudes (S.No. 2 -11 &13) in Table 6.11. The soil gas radon study in Balakot was
carried along active Balakot-Bagh (B-B) fault line in the 16 km section in length and
7.8 km in width lies between 34.50º–34.58º N latitude and 73.28º–73.38º E longitude
which covered about 125 square kilometer area.
The soil gas samples at each site were collected with the help of a probe,
engrossed in the soil to a depth of about 90 cm, which was then connected to the
7RAD Detector with a special accessory for the purpose. The probe was penetrated
inside the soil with a rotating handle or immersed with placid strokes of a hammer
where the soil was hard. The water lock and measuring instrument were then attached
to the probe for sucking soil gas from the deep soil. The soil gas was sucked through
the tube pipe into the measuring instrument for 5 minutes pumping phase and then the
data along with the respective bar charts and cumulative spectra of each sample were
printed out on the printer attached with the instrument. The sniff protocol and Grab
mode were used for the soil gas samplings on 7RAD at each site.
5.3 Indoor radon concentrations
Methodological studies were carried out to measure the indoor radon levels in five
districts of the N.W.F.P (Khyber Pakhtun Khwa), namely Haripur, Abbottabad,
Mansehra, Battgram and Kohistan in different season in order to find out the seasonal
and spatial variations in the indoor radon levels. This study will provide a baseline
data for these areas which would be of great help for radiological database of
Pakistan. In addition to these weighted average indoor radon concentrations and
seasonal correction factors were also determined because no such data was available
for this area for calculating the annual effective dose.
Most of the houses were built of bricks, sand, cement, wood etc. in each
district. A total 120 houses were surveyed for seasonal and yearly measurements for
the indoor radon concentrations. Twenty each in Balakot, Abbottabad, Mansehra,
Haripur, Battgram and Kohistan. These houses were in the radius of 1km, the nature
of the houses was both single and double stories and each house consists of two to
three rooms having at least two windows. The ventilation system of the houses in
54
Abbottabad was good while the other districts houses have poor natural ventilation.
More than that the houses of district Kohistan, Battgram and most of the hilly area
have closed type ventilation system and used the wood as the fire tool for heating and
cooking purposes inside the houses which may be the other reason for high indoor
radon concentration.
In Abbottabad, Mansehra and Haripur double story houses and in the
remaining part of the study area single story houses were selected. This arrangement
had been done to find some correlation of indoor radon concentrations with height of
the floors. Similarly the houses surveyed, were divided in to three categories (i) mud
made (ii) bricks made and (iii) concrete made. In this survey 58%, 27% and 15%
houses were concrete, mud and bricks made respectively.
5.3.1 Sampling
Large size sheets of 39CR having thickness of m500 were taken. These were
provided by Page Mouldings, Ltd.,UK . The sheets were cut into small parts each of
size 2 × 2cm . Some of the detectors were placed in the refrigerator for the
background measurement and the remaining detectors were set inside the NRPB radon
dosimeter holders. The assembly of the dosimeter is shown in the Fig. 4.2(c) which is
the diffusion cup and designed by the Radiation Protection Division of the Health
Protection Agency (HPA) previously known as National Radiological Protection
Board (UK ). Radon gas diffuses into the dosimeter and expose 39CR detector
[163].
A total of 1260 dosimeters with 39CR were installed, at height of 1.8-2.1m
in the living rooms and bedrooms of the chosen houses. One each dosimeter was
installed in the bedroom and living room of the selected house (2 dosimeters per
house). Out of the total samples 1200 were collected while the remaining 60 were lost
for different reasons. These dosimeters were allowed to expose to indoor radon for
one year (1st March 2008 to 28 February 2009) in four cycles and in the same period
for one year. 160 samples, eighty each for living and bedrooms were collected in each
one year on the seasonal basis(40 per season) and 40 samples each twenty for living
and bedrooms were collected on the year basis, each in Balakot, Abbottabad,
Mansehra, Haripur, Battgram and Kohistan. However weighted indoor radon level,
was calculated for each house (H.No. 1-20 for each season and for the year in the
55
Tables 6.12, 6.13, 6.14, 6.15 & 6.16 respectively) in the present case by using the
relation (5.3).
In this area of the Pakistan the winter season is long while the summer season
is short; the temperature in the summer is not more than 40 ºC and the temperature in
the winter fall below the freezing point of the water. Dosimeters were installed for
year long measurements in the living rooms of the studied houses in order to find the
effect of long term exposure on the 39CR detectors. After exposure to radon,
39CR detectors were etched in 25% NaOH at 80 ºC for 14 h and tracks were
counted using an optical microscope. After correcting for the background, track
densities were then related to the radon concentration level using calibration factor of
2.7 1112 )( mkBqhcmtracks [102, 163]. Annual average was calculated from the
measurements taken in the above long exposed detectors. By dividing the arithmetic
average of each season by the annual arithmetic average seasonal correction factor
was calculated [164]. The weighted average Rn222 concentrations ( ARnW ) were
calculated using the following formula:
4.0ARnW slivingroom bedrooms6.0 (5.3)
After through social survey of the area it was come to know that the people of
the area spent nearly 60% of their indoor time in bedrooms and 40% of their indoor
time in living rooms. Similarly weighted seasonal correction factors were determined.
Radon and its decay products contribute about 60% of the total annual
effective dose from all natural sources [166]. Radon is most effective in the indoor
atmosphere of dwellings and work places as the health related hazards of radon arise
because of the inhalation of air containing radon and its decay progenies. For indoor
air, the annual mean effective dose was calculated by using the parameters adopted by
a reportUNSCEAR 2000, [25].
DCFOFCamSvH Rn )( 1 (5.4)
Where H is the annual mean effective dose in 1amSv ,
RnC is the indoor radon concentration ( 3mBq ),
F is the equilibrium factor between radon and its decay products (0.45),
O is the average indoor occupancy time per person (7000 h a-1)
56
and DCF is the Dose Conversion Factor for radon exposure [9nSvh-1 ( 3mBq )-1].
All these samples were collected for one year in different seasons of 2009,
namely winter (December to February), spring (March to May), summer (June to
August) and autumn (September to November), from which some correlations among
radon level in different seasons have established. Similarly doses have been calculated
for the study area. The variations in temperature of the study area during this period
were observed from -4 to 10 ºC, 12 to 30 ºC, 16 to 38 ºC and 10 to 28 ºC in winter,
spring, summer and autumn respectively.
57
CHAPTER 6
RESULTS AND DISCUSSIONS
In this chapter, the results of radon concentrations in all three media, namely indoor
air, drinking water and soil gas are presented and discussed. At first, the radon
concentrations were measured in three types of drinking water sources i.e. bore/deep
well water, spring water and surface (river and nallah) water. The doses associated
with these sources of drinking water were calculated from the radon levels.
The radon levels in different water sources of all sampling sites were
measured and then the radon concentration in spring water of other sites of the study
area were compared with that of Balakot site, which lies on an active geological fault
line.
The radon concentrations in soil gas samples were measured in the five
districts of the study area. The measurements were taken along the transact from
Balakot- Bagh fault line in the Balakot section and were then compared with soil gas
radon concentrations of the remaining part of the study area.
In the last, the indoor radon levels (weighted average values) were carefully
determined in four seasons at all five districts including that of Balakot. The results of
Balakot are of special importance due its geology and its proximity with the fault line
known as Balakot-Bagh Fault line (B-B Fault line). The results are compared with
those of other sites of the study area.
The seasonal correction factors were employed for the calculation of seasonal
radon levels at each site. The annual mean indoor radon levels were determined and
compared with seasonal mean values. The similar or otherwise, the results have been
discussed in detail in the subsequent sections. The indoor radon levels were also
analyzed for different structures, stories of the houses in different sites of the study
area and finally, dose contributions from the weighted annual mean indoor radon
levels were estimated.
6.1 Radon concentration in water sources
In situ measurements of radon concentrations were taken in all three types of drinking
water sources (spring, surface and bore/well) by collecting samples from the study
58
area. Spring, surface and bore/well water samples from Balakot city and its
surroundings (especially near the fault line where there is no other source of water
except spring water), were collected in which spring water from fault line was treated
as a special case due to its past history of severe earth-quake on October 8, 2005. The
measurements of radon concentration in spring water samples from Balakot were
clearly different than the spring water samples of other sites in the study area is shown
in Table 6.5.
Table 6.1, 6.2 and 6.3 show the statistical analysis of spring, surface, bore hole
water respectively, while Table 6.4 shows the statistical analysis of all drinking
sources, from the selected sites in whole study area.
From Table 6.1 the data for the Balakot followed that most (75% of the total)
of the spring waters samples have radon concentrations within 18-21 3mkBq and very
few are below 19 kBq m-3. As compare to other parts of the study area in which only
5% of the total are fall in this limit (18-21 3mkBq ) and the remaining are well below
the said limit.
Sampling data for surface water from Table 6.2 shows that most (74% of the total) of
the samples have radon concentrations in the range of 1.7 to 9.0 3mkBq and only 2
values are in the range of 12 to 15 3mkBq . Table 6.3 shows that most (58% of the
total) of the samples have radon levels within 12-21 3mkBq and very few (4% of the
total) are above 24 3mkBq . Table 6.4 shows the statistical analysis for all types of
drinking sources from selected points in whole study, it revealed that most (23.6% of
the total) of samples have radon levels within 6-9 3mkBq .
Table 6.5 shows radon concentrations in the spring water, ranging from 15.1 to
22.9 3mkBq , 3.6 to 20.6 3mkBq , 5.8 to 15.3 3mkBq , 9.3 to 16.9 3mkBq and 6.3 to
20.4 3mkBq in Balakot, Abbottabad, Haripur, Battgram, and Kohistan respectively
with the mean values of 19.4 ± 2.0 3mkBq ,7.7 ± 4.0 3mkBq ,9.4 ± 2.7 3mkBq ,12.8
± 3.78 3mkBq and 13.3 ± 4.2 3mkBq .
Tables 6.6 and 6.7 contain all measurements of water samples of surface and
bore-hole/well sources collected from different sites of the study area. The results
obtained from these measurements reveal that radon concentrations in surface water
are in the range from 1.7 to 5.4 3mkBq , 4.9 to 11.8 3mkBq , 4.5 to 10.2 3mkBq , 4.8
59
to 13.8 3mkBq , 5.4 to 12.3 3mkBq and 7.4 to 11.8 3mkBq in Abbottabad,
Mansehra, Haripur, Battgram, Kohistan and Balakot respectively with the mean
values of 2.8 ± 0.90 3mkBq , 8.3 ± 1.5 3mkBq , 6.7 ± 1.8 3mkBq , 7.6 ± 2.5 3mkBq ,
9.2 ± 2.1 3mkBq and 9.2 ± 1.3 3mkBq . Similarly radon concentrations in bore water
samples are ranging from 7.0 to 24.0 3mkBq , 17.3 to 24.5 3mkBq , 9.5 to
25.4 3mkBq , 13.9 to 22.3 3mkBq , 14.3 to 23.1 3mkBq and 18.6 to 24.5 3mkBq in
Abbottabad, Mansehra, Haripur, Battgram, Kohistan and in Balakot respectively with
their mean values of 9.4 ± 3.7 3mkBq , 20.4 ± 1.6 3mkBq , 16.3 ± 4.8 3mkBq , 17.6 ±
2.4 3mkBq , 18.7 ± 2.9 3mkBq and 20.9 ± 1.8 3mkBq . Table 6.8 shows the
comparison of our observations in bore water samples with that of various studies
carried out at different parts of the globe.
Fig. 6.1 demonstrates the frequency allocation of the radon concentrations in
the spring water from Balakot only. Fig. 6.2 demonstrates the frequency allocation of
radon concentrations in the spring water samples (except the spring water of
Mansehra) in the study area. Fig. 6.3 and 6.4 show the frequency allocation of radon
concentrations in surface and bore/well water samples respectively in the study area.
Fig. 6.5 shows the frequency allocation of radon concentrations in all types of water
sources from the whole study area. The results of mean radon concentrations obtained
from all drinking water sources (except the spring water of Mansehra) are
demonstrated in Fig. 6.6.
Fig. 6.7 shows the variation in radon concentrations of spring water samples
with longitude, next to the B-B fault line of Balakot section. Higher radon levels were
observed near the fault line with maximum value of 22.9 ± 3.7 3mkBq at longitude
73.34º E. High values of radon were found in the spring water samples composed
from the fault line of Balakot region, where the soil is permeable for the flow of radon
in the underlying rocks. Radium and radon are soluble in water. When ground water
moves through radium/radon behavior soil and rocks they are dissolved and
transported with the water. Faults, can accumulate uranium from circulating fluids,
and as a consequence, strongly enhance radon potential locally. The other important
reason may be the uranium deposits yet to be studied. The highest value of radon
concentration in spring water was found at 73.34º E longitude on Balakot-Bagh active
fault line as can be seen from the Fig. 6.7.
60
Large variations in radon levels were observed in the spring water of
Abbottabad. The reason for this may be the phosphate bearing rocks such as that
found in Kakul (one of Abbottabad site) which contain approximately 22 ppm
uranium [147]. While the rest of sampling points in the study areas do not show
significant variation in radon levels. This shows the positive correlation between
radon levels in water and the dissolved solids in Abbottabad region.
In surface water the radon levels were found almost consistent in the whole
study area and no large intra-site variations were observed in all sampling points. In
bore water, the maximum radon value was found in one sampling point at Haripur.
The reason may be the uranium deposits or the porosity of the soil which is
responsible on the large scale migration of the radium or radon to the water in the
under-lying rocks.
Bore-hole water samples were composed from the public water as well as
private water supply. However most (more than 80%) of the samples were from
public water supply and the rest from private supply. The water samples were
collected at different depths. These depths are ranging from 60 to 90m. However no
correlation was found between the depth of the well and the water radon
concentration from Table 6.9.
Mean radon levels in the bore water of all districts except Abbottabad are
above the EPAUS recommended level (11.0 3mkBq )[ 167]. The mean radon levels
in the surface water of the whole study area are lying within the suggested
EPAUS limit. The mean radon levels in the spring water samples of Balakot,
Battgram and Kohistan are found above the EPAUS recommended value but the
observed mean values are within the range of radioprotection standards recommended
by some European countries.
The average radon levels in the spring and bore water samples of the whole
study area are higher than the maximum contamination level )(MCL which is 11.0 3mkBq while in the surface water the radon levels are below the said limit.
Therefore the waters of the areas where the drinking sources are spring and bore hole,
must not be used, before some remedial steps are to be taken, which include the
aeration and filtration through charcoal filter. The uncertainties in measurements that
are given in the tables, figures and text include both statistical and systematic errors
[168].
61
Table 6.1: Statistical analysis of spring water sampling data from the selected springs in
whole study area.
Range of 222Rn content )( 3mkBq
Frequency Percentage frequency Cumulative frequency
Abbottabad 0-3
3.1-6 6.1-9 9.1-12 12.1-15 15.1-18 18.1-21 21.1-24 24.1-27
0 5 7 2 0 0 1 0 0
0
33.3 46.6 13.3
0 0
6.6 0 0
0
33.33 79.99 93.32 93.32 93.32
100.00 100.00 100.00
Haripur 0-3
3.1-6 6.1-9 9.1-12 12.1-15 15.1-18 18.1-21 21.1-24 24.1-27
0 1 6 5 2 1 0 0 0
0
6.6 40
33.3 13.33 6.6 0 0 0
0
6.66 46.66 79.99 93.32
100.00 100.00 100.00
Battgram
0-3 3.1-6 6.1-9 9.1-12 12.1-15 15.1-18 18.1-21 21.1-24 24.1-27
0 0 0 3 7 5 0 0 0
0 0 0 20
46.6 33.3
0 0 0
0 0 0 20
66.66 100.00 100.00 100.00 100.00
Kohistan 0-3
3.1-6 6.1-9 9.1-12 12.1-15 15.1-18 18.1-21 21.1-24 24.1-27
0 0 4 2 4 2 2 1 0
0 0
26.6 13.3 26.6 13.3 13.3 6.6 0
0 0
26.66 39.99 66.65 79.98 93.31
100.00 100.00
62
Balakot 0-3
3.1-6 6.1-9 9.1-12 12.1-15 15.1-18 18.1-21 21.1-24 24.1-27
0 0 0 0 0 2 9 1 0
0 0 0 0 0
16.6 75.0 8.3 0
0 0 0 0 0
16.66 91.66
100.00 100.00
Table 6.2: Statistical analysis of surface water sampling data from the selected surface water
in whole study area.
Range of 222Rn content )( 3mkBq
Frequency Percentage frequency Cumulative frequency
Abbottabad 0-3
3.1-6 6.1-9 9.1-12 12.1-15
14 6 0 0 0
70.0 30.0
0 0 0
70.0
100.0 100.0 100.0 100.0
Mansehra 0-3
3.1-6 6.1-9 9.1-12 12.1-15
0 1 17 6 0
0
4.1 70.8 25.0
0
0
4.16 74.99 100.00 100.00
Haripur 0-3
3.1-6 6.1-9 9.1-12 12.1-15
0 7 5 2 0
0
50.0 35.7 14.2
0
0
50.0 85.71 100.00 100.00
Battgram 0-3
3.1-6 6.1-9 9.1-12 12.1-15
0 3 5 2 1
0
27.2 45.4 18.1 9.09
0
27.27 72.72 90.90 100.00
Kohistan 0-3
3.1-6 6.1-9 9.1-12 12.1-15
0 2 3 6 2
0
15.3 23.0 46.1 15.3
0
15.38 38.45 84.60 100.00
Balakot 0-3
3.1-6
0 0
0 0
0 0
63
6.1-9 9.1-12 12.1-15
6 5 0
54.5 45.4
0
54.54 100.00 100.00
Table 6.3: Statistical analysis of bore-hole water sampling data from the selected wells in
whole study area.
Range of 222Rn content )( 3mkBq
Frequency Percentage frequency Cumulative frequency
Abbottabad 0-3
3.1-6 6.1-9 9.1-12 12.1-15 15.1-18 18.1-21 21.1-24 24.1-27
0 0 13 4 1 0 0 1 0
0 0
68.4 21.0 5.2 0 0
5.2 0
0 0
68.42 89.47 94.73 94.73 94.73 100.00 100.00
Mansehra 0-3
3.1-6 6.1-9 9.1-12 12.1-15 15.1-18 18.1-21 21.1-24 24.1-27
0 0 0 0 0 1 15 6 1
0 0 0 0 0
4.3 65.2 26.0 4.3
0 0 0 0 0
4.34 69.55 95.56 100.00
Haripur 0-3
3.1-6 6.1-9 9.1-12 12.1-15 15.1-18 18.1-21 21.1-24 24.1-27
0 0 0 8 5 6 5 3 3
0 0 0
26.6 16.6 20.0 16.6 10.0 10.0
0 0 0
26.66 43.32 63.32 79.98 89.98 100.00
Battgram 0-3
3.1-6 6.1-9 9.1-12 12.1-15 15.1-18 18.1-21 21.1-24 24.1-27
0 0 0 0 4 6 7 2 0
0 0 0 0
21.0 31.5 36.8 10.5
0
0 0 0 0
21.05 52.62 89.46 100.00 100.00
Kohistan
64
0-3 3.1-6 6.1-9 9.1-12 12.1-15 15.1-18 18.1-21 21.1-24 24.1-27
0 0 0 0 2 3 2 4 0
0 0 0 0
18.1 27.2 18.1 36.3
0
0 0 0 0
18.18 45.45 63.63 100.00 100.00
Balakot 0-3
3.1-6 6.1-9 9.1-12 12.1-15 15.1-18 18.1-21 21.1-24 24.1-27
0 0 0 0 0 0 6 5 1
0 0 0 0 0 0 50
41.6 8.3
0 0 0 0 0 0
50.0 91.66 100.00
Table 6.4: Statistical analysis of all types of drinking sources sampling data from the selected
springs, surface and wells in whole study area.
Range of 222Rn content )( 3mkBq
Frequency Percentage frequency Cumulative frequency
Abbottabad
0-3
3.1-6
6.1-9
9.1-12
12.1-15
15.1-18
18.1-21
21.1-24
24.1-27
14
11
20
6
1
0
1
1
0
25.9
20.3
37.0
11.1
1.8
0
1.8
1.8
0
29.92
46.29
83.32
94.43
96.28
96.28
98.13
100.00
100.00
Mansehra
0-3
3.1-6
6.1-9
9.1-12
12.1-15
15.1-18
0
1
17
6
0
1
0
2.1
36.1
12.7
0
2.1
0
2.12
38.29
51.05
51.05
53.17
65
18.1-21
21.1-24
24.1-27
15
6
1
31.9
12.7
2.1
85.08
97.78
100.00
Haripur
0-3
3.1-6
6.1-9
9.1-12
12.1-15
15.1-18
18.1-21
21.1-24
24.1-27
0
8
11
15
7
7
5
3
3
0
13.5
18.6
25.4
11.8
11.8
8.4
5.0
5.0
0
13.55
32.19
57.61
69.47
81.33
89.80
94.88
100.00
Battgram
0-3
3.1-6
6.1-9
9.1-12
12.1-15
15.1-18
18.1-21
21.1-24
24.1-27
0
3
5
5
12
11
7
2
0
0
6.6
11.1
11.11
26.6
24.4
15.5
4.4
0
0
6.66
17.77
28.88
55.54
79.98
95.53
100.00
100.00
Kohistan
0-3
3.1-6
6.1-9
9.1-12
12.1-15
15.1-18
18.1-21
21.1-24
24.1-27
0
2
7
8
8
5
4
5
0
0
5.1
17.9
20.5
20.5
12.8
10.2
12.8
0
0
5.12
23.06
43.57
64.08
76.90
87.15
100.00
100.00
Balakot
0-3
0
0
0
66
3.1-6
6.1-9
9.1-12
12.1-15
15.1-18
18.1-21
21.1-24
24.1-27
0
6
5
0
2
15
6
1
0
17.1
14.2
0
5.7
42.8
17.1
2.8
0
17.14
31.42
31.42
37.13
79.98
97.12
100.00
Table 6.5: Radon concentrations in the spring water in )( 3mkBq .
Balakot Abbottabad Haripur Battgram Kohistan 1. 21.9±3.1 9.3±1.5 6.2±1.3 14.1±1.6 16.3±2.0 2. ---------- 9.6±1.4 7.9±1.4 9.3±1.1 17.1±2.3 3. 19.7±2.5 6.8±1.1 11.1±1.6 14.0±2.0 18.4±2.4 4. 18.4±3.2 5.4±0.9 5.8±1.3 13.4±1.6 6.3±1.1 5. 15.1±2.1 9.0±1.0 10.3±1.4 12.8±1.5 12.4±1.7 6. 19.8±3.6 20.6±2.6 9.2±1.3 12.7±1.7 9.4±1.5 7. 20.3±3.8 4.5±1.0 10.2±1.5 10.4±1.3 8.7±1.4 8. 20.9±3.3 3.6±0.7 12.5±1.6 15.6±1.8 11.3±1.7 9. 22.9±3.7 6.7±1.2 6.9±1.0 13.7±1.7 19.6±2.8 10. ---------- 8.4±1.5 7.2±1.1 12.9±1.8 20.4±2.6 11. 19.6±3.1 3.7±0.4 6.4±1.2 15.4±1.6 8.9±1.3 12. ---------- 6.7±1.2 9.7±1.4 15.3±1.9 13.7±1.6 13. 19.1±2.9 8.4±1.5 15.3±1.7 12.0±1.4 14.9±1.7 14. 16.8±2.5 4.2±0.9 13.4±1.3 16.7±1.6 13.2±1.7 15. 18.9±2.6 8.5±0.9 9.2±1.2 16.9±1.3 8.8±1.1
A.M 19.4 7.7 9.4 12.8 13.3 S.D 2.0 4.0 2.7 3.78 4.2
Maximum 22.9 20.6 15.3 16.9 20.4 Minimum 15.1 3.6 5.8 9.3 6.3
Range 15.1-22.9 3.6-20.6 5.8-15.3 9.3-16.9 6.3-20.4
Table 6.6: The radon concentration )( 3mkBq in surface and borehole water in three districts,
Abbottabad, Mansehra and Haripur.
Abbottabad Mansehra Haripur Surface Borehole Surface Borehole Surface Borehole
1. 5.4±1.0 9.0±1.0 10.0±1.6 22.5±3.2 4.9±0.5 10.1±1.7 2. 3.0±0.6 10.2±0.9 8.9±1.3 21.1±3.1 ---------- 11.6±1.8 3. 3.5±0.8 8.8±1.2 8.1±1.2 19.8±2.9 4.6±0.7 14.9±1.9 4. 2.1±0.5 7.0±1.0 9.5±1.7 18.7±2.7 ---------- 19.6±1.8 5. 2.5±0.3 9.8±1.1 10.3±1.8 19.3±2.8 5.7±0.9 21.5±2.1 6. 3.8±0.7 12.3±1.1 11.8±1.4 22.8±3.2 6.3±1.2 24.8±2.4 7. 1.9±0.4 7.7±0.9 7.9±1.1 22.9±3.1 ---------- 13.3±1.5 8. 3.9±0.9 8.1±1.2 10.7±1.3 24.5±3.3 ---------- 9.5±1.7
67
9. 2.7±0.4 --------- --------- 20.5±2.9 7.5±1.3 9.8±1.8 10. 1.8±0.3 7.2±0.9 7.8±1.2 21.4±2.8 ---------- 10.2±2.0 11. 2.1±0.2 9.2±1.0 7.4±1.1 19.5±2.5 ---------- 10.4±1.8 12. 3.2±0.6 8.9±1.0 8.4±1.4 18.6±2.2 4.5±0.6 11.6±2.3 13. 2.4±0.6 7.5±0.8 9.7±1.6 19.7±2.5 9.6±1.5 23.4±3.0 14. 1.7±0.2 7.1±0.9 8.3±1.5 20.3±2.8 ---------- 20.1±2.3 15. 3.8±0.8 24.0±1.6 7.3±1.3 20.0±2.7 ---------- 19.7±2.2 16. 2.8±0.7 8.0±1.3 6.7±1.0 17.3±2.2 8.7±1.4 25.4±2.8 17. 2.1±0.5 7.2±0.7 6.8±1.1 18.4±2.5 10.2±1.7 24.6±2.5 18. 2.2±0.5 8.3±1.1 8.0±1.4 20.7±2.9 7.9±1.2 15.7±1.9 19. 2.4±0.3 9.1±1.0 7.2±1.3 ---------- ---------- 16.2±2.3 20. 2.1±0.4 8.4±0.9 8.6±1.6 20.4±2.9 ---------- 11.8±1.7 21. ---------- ---------- 4.9±0.9 ---------- ---------- 18.7±2.9 22. ---------- ---------- 7.6±1.7 20.8±2.8 7.3±1.1 17.4±2.5 23. ---------- ---------- 8.4±1.8 19.2±2.7 5.4±1.2 17.6±2.7 24. ---------- ---------- 7.0±1.7 21.2±2.9 ---------- 16.4±2.5 25. ---------- ---------- 7.9±1.6 20.0±2.7 ---------- 13.4±1.9 26. ---------- ---------- ---------- ---------- 5.9±1.3 18.9±2.5 27. ---------- ---------- ---------- ---------- ---------- 22.4±3.1 28. ---------- ---------- ---------- ---------- 5.3±1.1 12.8±1.8 29. ---------- ---------- ---------- ---------- ---------- 16.5±2.4 30. ---------- ---------- ---------- ---------- ---------- 10.7±2.3
Mean 2.8 9.4 8.3 20.4 6.7 16.3 S.D 0.90 3.7 1.5 1.6 1.8 4.8
Maximum 5.4 24.0 11.8 24.5 10.2 25.4 Minimum 1.7 7.0 4.9 17.3 4.5 9.5
Range 1.7-5.4 7.0-24.0 4.9-11.8 17.3-24.5 4.5-10.2 9.5-25.4
Table 6.7: The radon concentration )( 3mkBq in surface and borehole water in Battgram,
Kohistan and Balakot.
Battgram Kohistan Balakot S.No. Surface Borehole Surface Borehole Surface Borehole
1. 5.4±0.7 22.3±3.2 8.7±1.3 17.2±2.5 10.0±1.6 22.5±3.2 2. ---------- 17.4±3.0 ---------- ---------- ---------- ---------- 3. ---------- 13.9±2.2 ---------- ---------- 8.9±1.4 21.1±3.3 4. ---------- 16.5±2.4 7.9±1.2 ---------- ---------- ---------- 5. 7.6±1.5 18.6±3.1 ---------- 19.3±2.6 8.1±1.3 19.8±3.0 6. ---------- 14.7±2.3 10.6±1.5 ---------- 9.5±1.7 ---------- 7. ---------- ---------- ---------- ---------- ---------- ---------- 8. 9.7±1.9 15.1±2.8 ---------- ---------- ---------- 18.7±2.8 9. 6.3±1.4 14.8±2.1 10.3±1.4 21.5±2.4 10.3±1.7 ---------- 10. ---------- 19.7±3.2 10.7±1.5 ---------- ---------- 19.3±2.9 11. 4.8±0.6 ---------- ---------- ---------- 11.8±1.9 22.8±3.1 12. ---------- 15.8±2.1 9.7±1.4 14.3±2.1 ---------- ---------- 13. ---------- ---------- ---------- ---------- 7.9±1.3 ---------- 14. 6.7±1.6 16.9±2.3 9.8±1.3 ---------- 10.7±1.7 22.9±3.2 15. 13.8± 2.1 18.3±2.7 ---------- 18.6±2.5 ---------- ---------- 16. ---------- ---------- ---------- 16.1±2.3 7.8±1.2 ----------
68
17. ---------- 18.5±2.8 5.4±0.7 ---------- ---------- ---------- 18. ---------- 20.8±3.4 ---------- ---------- ---------- 24.5±3.4 19. 8.4±1.9 ---------- 9.1±1.3 22.3±4.0 7.4±1.3 ---------- 20. ---------- 21.4±3.3 ---------- ---------- ---------- ---------- 21. ---------- ---------- 12.3±1.7 21.9±3.9 ---------- 20.5±3.1 22. 9.3±2.1 ---------- 12.1±1.7 ---------- ---------- ---------- 23. ---------- 19.9±2.9 ---------- ---------- 8.4±1.4 ---------- 24. ---------- 18.8±2.7 ---------- 23.1±3.4 ---------- 21.4±3.0 25. 6.9±1.8 14.7±1.9 ---------- ---------- ---------- 19.5±2.7 26. ---------- ---------- 5.9±0.7 16.4±3.0 ---------- ---------- 27. 5.3±0.9 ---------- ---------- ---------- ---------- ---------- 28. ---------- 15.7±2.5 7.1±1.1 ---------- ---------- 18.6±2.6 29. ---------- ---------- 14.9±2.7 ---------- ----------
Mean 7.6 17.6 9.2 18.7 9.2 20.9 S.D 2.5 2.4 2.1 2.9 1.3 1.8
Maximum 13.8 22.3 12.3 23.1 11.8 24.5 Minimum 4.8 13.9 5.4 14.3 7.4 18.6
Range 4.8-13.8 13.9-22.0 5.4-12.3 14.3-23 7.4-11.8 18.6-24.5
Table 6.8: The comparison of radon concentration )( 3mkBq in deep well water with
previous measurements from different countries
Country name Average Range Reference Canada 31.7 0-336 [169] Finland 60 ------- [169] Romania 15.8 0.6-112.6 [170] Sweden 38 ------- [171] USA ---------- 74%<74&5%>370 [172] Pakistan 17.2 7.0-25.4 (Present work for bore hole water)
6.1.1 Dose calculation from radon concentrations in water
As far as the radiation dose to inhabitants from waterborne radon is concerned, it is
understood to be a higher risk than all other impurities in water [173]. The annual
mean effective doses for ingestion and inhalation were evaluated by using the
parameters recognized in 2000,UNSCEAR [25] as follow,
EDCCCamSvE wRnWwIg )( 1 (6.1)
Where wIgE is the effective dose for ingestion,
RnWC and wC are the radon concentration in water )( 3mkBq and weighted estimate of
water consumption (60 l a-1) respectively.
EDC is the Effective Dose Coefficient for ingestion 3.5 1BqnSv .
69
DCFOFRCamSvE awRnWwIh )( 1 (6.2)
Where wIhE is the effective dose for inhalation,
awR is the ratio of radon in air to radon in tap water (10-4),
F is the equilibrium factor between radon and its decay products (0.45), O is the
average indoor occupancy time per person (7000 h a-1)
DCF is the Dose Conversion Factor for radon exposure 131 )(9 mBqhnSv .
The simplified relation from the above two relations is
00273.0)( 1RnCamSvH 131 )(9 mBqamSv (6.3)
RnC is the radon concentration in 3mBq
Table 6.9 is summary of the results for the radon concentrations in all drinking
water sources along with the results of associated doses which the people received.
The result shows that the dose calculated from radon in all drinking sources in the
whole study area is 0.034 mSv (mean for the whole study area) per year.
Fig.6.8 is the demonstration of the results obtained for annual mean doses
from all, three sources (except the spring water of Mansehra) of drinking water.
Table 6.9: Arithmetic mean (A.M), maximum and minimum radon concentration and annual
mean dose estimation from radon in all three sources of drinking water in the
study area.
District name (sample nature)
Radon concentration )( 3mkBq
A.M Max: Min:
Dose estimation ( 1amSv )
A.M Max: Min:
S.D
Abbottabad Spring Surface
Bore Total
7.7 2.8 9.4 6.6
20.6 5.4 24.0 24.0
3.6 1.7 7.0 1.7
0.021 0.008 0.026 0.018
0.056 0.015 0.066 0.065
0.0098 0.005 0.019 0.005
4.0 0.9 3.7
Mansehra Surface
Bore Total
8.3 20.4 14.3
11.8 24.5 24.5
4.9 17.3 4.9
0.022 0.056 0.039
0.032 0.067 0.067
0.013 0.047 0.013
1.5 1.6
Haripur Spring Surface
Bore Total
9.5 6.7 16.3 10.8
15.3 10.2 25.4 25.4
5.8 4.5 9.5 4.5
0.026 0.018 0.044 0.029
0.042 0.028 0.069 0.069
0.016 0.012 0.029 0.012
2.7 1.8 4.8
Battgram Spring
12.8
19.6
9.3
0.035
0.054
0.025
3.78
70
Surface Bore Total
7.6 17.6 12.6
13.8 22.3 22.3
4.8 13.9 4.8
0.021 0.046 0.034
0.038 0.073 0.073
0.013 0.038 0.013
2.47 2.44
Kohistan Spring Surface
Bore Total
13.3 9.2 18.6 13.7
20.4 12.3 23.1 23.1
6.3 5.4 14.3 5.4
0.036 0.025 0.050 0.037
0.056 0.034 0.063 0.063
0.017 0.015 0.039 0.015
4.2 2
2.97
Balakot Spring Surface
Bore Total
19.4 9.2 20.9 16.5
22.9 11.8 24.5 24.5
15.12 7.4 18.6 7.4
0.053 0.025 0.057 0.045
0.062 0.032 0.067 0.067
0.041 0.020 0.051 0.044
2
1.3 1.8
6.2 Soil gas radon concentrations
Table 6.10 contains the measurements of soil gas radon concentrations at different
sites of the study area. The radon levels are in the range from 8.7 to 20.1 3mkBq , 2.3
to 7.3 3mkBq , 4.6 to 12.3 3mkBq , 3.9 to 11.0 3mkBq , and 4.5 to 12.4 3mkBq with
their mean values of 11.9 ± 3.2 3mkBq , 4.3 ± 1.4 3mkBq , 7.4 ± 2.4 3mkBq , 6.8 ±
2.3 3mkBq and 7.5 ± 2.4 3mkBq in Balakot, Abbottabad, Haripur, Battgram and
Kohistan respectively.
Fig. 6.9 illustrates the frequency allocation of soil gas radon concentrations in
the whole study area, while Fig. 6.10 demonstrates the frequency distribution of soil
gas radon concentrations at and around Balakot region. The individual frequency
distribution at each district looks like normal distribution as is clear in Fig. 6.9. As
seen from the figure that most of the soil gas radon concentrations in the study area
were within the range of 3-15 3mkBq with few values are high soil gas radon
concentrations. Similar normal distribution is evidenced from Fig. 6.10 for Balakot
region with a central value of 11.66 ± 0.25 3mkBq . Fig. 6.11 illustrates the mean soil
gas radon concentrations in the whole study area and Fig. 6.12 shows the soil gas
radon concentrations variation, next to the Balakot-Bagh (B-B) fault line in Balakot.
Higher radon levels were observed near the fault line with the maximum value of 20.1
± 2.5 3mkBq at 73.34º E longitudes. The underlying cracks in the rocks near the
fault line may be the one probable reason for the higher radon levels besides the other
71
reasons including higher uranium and thorium concentrations, porosity of the soil and
lithology of the site, which are yet to be studied.
Table 6.10: Radon concentration 3mkBq in soil gas in Balakot (near fault line) and other
part of the study area
Sample No Balakot Abbottabad Haripur Battgram Kohistan 1. ---------- 2.3±0.2 5.8±0.7 4.0±0.4 6.0±0.5 2. 15.0±1.5 3.4±0.3 4.9±0.9 3.9±0.3 5.8±0.7 3. 20.1±2.5 5.0±0.5 5.7±0.8 4.4±0.6 6.3±0.3 4. 13.1±1.4 4.0±0.4 5.9±0.6 7.8±0.9 7.4±0.6 5. 12.4±1.3 6.2±0.8 4.8±0.5 4.1±0.5 4.5±0.3 6. 12.3±1.4 4.6±0.7 9.0±0.9 9.4±1.2 6.9±0.4 7. 10.4±1.2 7.3±0.8 10.5±1.2 5.1±0.4 7.3±0.8 8. 9.1±1.1 2.8±0.3 10.6±1.1 7.8±0.8 12.2±1.3 9. 8.7±1.0 5.7±0.6 8.9±0.9 8.2±1.0 8.4±1.1 10. 9.0±0.9 5.0±0.5 7.6±0.8 8.9±0.9 10.0±1.2 11. 9.2±1.1 3.4±0.4 12.3±1.3 7.6±0.8 7.0±0.2 12. ---------- 3.3±0.5 5.6±0.6 11.0±1.5 12.4±1.7 13. 11.4±0.8 3.0±0.5 4.6±0.7 4.5±0.3 4.6±0.3 14. ---------- 3.6±0.4 7.4±0.8 8.0±0.3 6.5±0.4
Mean 11.9 4.3 7.4 6.8 7.5 S.D 3.2 1.4 2.4 2.3 2.4
Maximum 20.1 7.3 12.3 11.0 12.4 Minimum 8.7 2.3 4.6 3.9 4.5
Range 8.7-20.1 2.3-7.3 4.6-12.3 3.9-11.0 4.5-12.4
6.3 Results of the indoor radon concentrations
From the measured track densities of 39CR with known calibration factor of
1312 )(7.2 mkBqhcmtracks [102, 163]. Indoor radon concentrations and seasonal
correction factors were determined in Hazara division of N.W.F.P for each of the four
seasons. Table 6.11-6.15 show a clear picture of the seasonal average and annual
mean in all five districts along with Balakot. The indoor radon concentrations in all
five districts are maximum in winter seasons and minimum in the summer seasons
except the district Haripur where it is minimum in the autumn season.
Table 6.11 is the measurements of indoor radon concentrations in spring
season. These values range from 70 to 150 3mBq , from 49 to 128 3mBq , from 54
to 148 3mBq , from 56 to 154 3mBq , from 50 to 148 3mBq and from 55 to
156 3mBq in Balakot, Abbottabad, Mansehra, Haripur, Battgram and Kohistan
respectively, with their respective mean values of 132 ± 21 3mBq , 108 ± 20 3mBq ,
72
112 ± 38 3mBq , 124 ± 28 3mBq , 108 ± 30 3mBq , 116 ± 32 3mBq . Table 6.12
shows the measurements of indoor radon concentrations in summer season. These
values range from 65 to 144 3mBq , 41 to 126 3mBq , 49 to 144 3mBq , 110 to
182 3mBq , 48 to 135 3mBq and 53 to 152 3mBq in Balakot, Abbottabad,
Mansehra, Haripur, Battgram and Kohistan respectively, with their respective mean
values of 120 ± 22 3mBq , 102 ± 23 3mBq , 106 ± 30 3mBq , 140 ± 23 3mBq , 102
± 26 3mBq and 114 ± 27 3mBq in Balakot, Abbottabad, Mansehra, Haripur,
Battgram and Kohistan. Table 6.13 reveals the measurements of indoor radon
concentrations in autumn season. These values are ranging from 119 to172 3mBq ,
from 98 to 155 3mBq , 108 to 172 3mBq , 51 to 145 3mBq , 102 to 174 3mBq and
108 to 190 3mBq in Balakot, Abbottabad, Mansehra, Haripur, Battgram and Kohistan
respectively, with their respective mean values of 151 ± 20 3mBq , 128 ± 18 3mBq ,
140 ± 21 3mBq , 114 ± 26 3mBq , 130 ± 20 3mBq and 147 ± 24 3mBq . Table 6.14
contains the measurements of indoor radon concentrations in the winter season.
Indoor radon values range from 163 to 220 3mBq , 130 to 210 3mBq , 156 to 174
3mBq , 155 to 230 3mBq and 134 to 254 3mBq in Balakot, Abbottabad, Mansehra,
Haripur, Battgram and Kohistan respectively, with their respective mean values of
204 ± 16 3mBq , 162 ± 21 3mBq , 172 ± 15 3mBq , 174 ± 18 3mBq , 170 ±
16 3mBq and 178 ± 24 3mBq . Table 6.15 reveals the results of weighted annual
mean indoor radon concentration on the basis of seasonal measurements, with the
values of 152 ± 20 3mBq , 125 ± 21 3mBq , 132 ± 24 3mBq , 138 ± 24 3mBq , 128
± 23 3mBq and 139 ± 26 3mBq in Balakot, Abbottabad, Mansehra, Haripur,
Battgram and Kohistan respectively.
Fig. 6.13 exhibits the frequency allocation of indoor radon concentrations in
Balakot region. The shape of frequency distribution is bimodal, one peak centres
about 140 3mBq and the second peak centres about 214 3mBq . The majority of the
values lie in the first peak ranging from 100-180 3mBq . While the frequency
allocation of the whole study area is depicted in Fig. 6.14. The shape of frequency
distribution is almost unimodal except Balakot. Most of the values lie in the range of
90-150 3mBq . Fig. 6.15 demonstrates the annual mean indoor radon concentration in
73
the study area. These values in the whole area, except Balakot, are within the
EPAUS recommended level of 14 lpCi (148 3mBq ). The mean value of Balakot is
slightly higher than the recommended limit, however, it is not high enough to cause
any health hazard to the inhabitant of the area. Fig. 6.16 shows the seasonal variation
of indoor radon concentrations in the study area. The radon levels in each district
including Balakot are higher in the winter season. The higher values in the winter
season are due to humid and closed indoor environments which retard the ventilation
rate in the season and lower values in the summer season because of high ventilation
rate and less humid environment, except at Haripur district where it is lower in the
autumn season. The probable reason of higher radon levels in summer than in autumn
is the unusual high rain fall at the sampling period at Haripur. The other reasons for
high indoor radon concentrations during winter season in the study area are: (a) soil
dampness and snow cover, which slow down radon gas flow into atmosphere; (b)
Pressure difference between the inside of a home (as the inside air is heated) and the
soil adjacent the home. Subsequently, the air pressure in homes to be lower than the
soil adjacent them. This results in radon gas seeping through groundwork openings
into the home directly.
Table 6.17 and 6.18 show the mean, maximum and minimum indoor radon
concentrations at different floors of the houses and in houses made of different
materials respectively. Fig.6.17 & 6.18 reveal the mean indoor radon concentrations
at different floors of the houses and houses made of different materials respectively.
6.3.1 Seasonal correction factor
Seasonal correction was calculated for all districts in the study area by dividing the
arithmetic average of each season by the annual arithmetic average [164]. Fig.6.19
reveals variations in the seasonal correction factor for each district. These values
ranging from 0.79 to1.34, 0.82 to 1.3, 0.80 to 1.3, 0.89 to 1.26, 0.79 to1.32 and 0.82
to 1.28 in Balakot, Abbottabad, Mansehra, Haripur, Battgram and Kohistan
respectively. This factor in the whole study area ranges from 0.79 to 1.34. The
calculated values are higher in winter and lower in summer.
6.3.2 Comparative study of yearly measured indoor radon and seasonal
average indoor radon concentrations
The data of weighted annual indoor radon concentrations obtained from the yearly
measurements in the whole study area has been given in Table 6.16. The average
74
values at Balakot, Abbottabad, Mansehra, Haripur, Battgram and Kohistan are
respectively 132 ± 17 3mBq , 105 ± 17 3mBq , 112 ± 15 3mBq , 117 ± 16 3mBq ,
111 ± 13 3mBq and 120 ± 16 3mBq . The comparison of annual average on the basis
of yearly measurements with the annual average on the basis of seasonal
measurements of indoor radon concentrations has been made in Fig.6.20. The yearly
measurements of indoor radon concentrations in the area are almost less than by 15%
from that of seasonally averaged indoor radon measurements. It is clear from Table
6.15 & 6.16 that annual radon concentrations on yearly basis are less than seasonal
annual average by 13%, 16%, 15%, 15%, 13% and 14% at Balakot, Abbottabad,
Mansehra, Haripur, Battgram and Kohistan respectively. The tendency, has several
reasons: (i) dust and other particles have penetrated into the dosimeter assembly and
settled on the surface of the CR-39 detector due to the year-long measurements,
subsequently, the efficiency of the detector has decreased (ii) heat and moisture in the
existence of oxygen in the air can have an adverse effect on the sensitivity of the
etched –track detector during radon measurement [174], and (iii) the deterioration of
detector materials for long exposure, the errors in the etching and counting
techniques may be responsible for the this deviation.
6.3.3 Variation of indoor radon concentrations in different stories and
construction materials
Table 6.17 shows the variation of indoor radon concentrations with height of floor.
The ground floor shows high indoor radon concentrations than the first floor. These
values ranging from 41 to 236 3mBq and 36 to 116 3mBq for ground and first floors
respectively. The mean values of radon concentrations on ground floors in
Abbottabad, Mansehra and Haripur districts are 125 ± 22 3mBq , 132 ± 23 3mBq ,
and 138 ± 24 3mBq respectively, while the mean indoor radon concentrations on the
first floors of these districts are 116 ± 16 3mBq , 122 ± 18 3mBq 138 ± 19 3mBq .
Fig. 6.17 depicts the mean indoor radon concentrations measured on the first and the
ground floors of the above mentioned districts. Lower indoor radon concentrations
were found on the first floors which were almost 14% less than that on the ground
floors. The reason for the lower radon concentrations on the first floors is their highly
ventilation conditions and low density of air because radon is a dense gas and
75
subsides close to the ground level. Table 6.18 encompassing the results obtained from
different construction used in the houses of the study area. Generally higher radon
concentrations were found in houses made of mud (adobe) as compared to houses
made of bricks and concrete.
From the obtained results, the mean indoor radon concentrations in houses
made of bricks, concrete and mud are 125 ± 18 3mBq , 60 ± 8 3mBq and 170 ±
22 3mBq , 129 ± 21 3mBq , 63 ± 9 3mBq and 201 ± 24 3mBq , 135 ± 17 3mBq ,
66 ± 8 3mBq and 210 ± 27 3mBq , 127 ± 16 3mBq , 61 ± 10 3mBq and 173 ±
23 3mBq and 134 ± 19 3mBq , 64 ± 8 3mBq and 207 ± 28 3mBq respectively in
Abbottabad, Mansehra, Haripur, Battgram and Kohistan. The reason for high radon
levels in houses made of mud compared to houses made of concrete and bricks made
houses are its comparatively high porosity and moist nature of mud made houses.
Fig. 6.18 demonstrates the variation of indoor radon concentrations in
different construction materials made houses.
6.3.4 Dose estimation from indoor radon concentrations
For indoor air, the annual mean effective dose was calculated using the Equation
(5.4). Table 6.19 shows the weighted indoor radon concentrations and their annual
mean doses to be received by the dwellings of the area, from indoor radon level. The
annual mean doses from indoor radon are 4.31 ± 0.56 mSv , 3.54 ± 0.59 mSv , 3.74 ±
0.71 mSv , 3.91 ± 0.71 mSv , 3.62 ± 0.82 mSv and 3.94 ± 0.73 mSv in Balakot,
Abbottabad, Mansehra, Haripur, Battgram and Kohistan respectively. Fig. 6.21
demonstrates the annual mean doses, received by the people of the area from indoor
radon concentrations.
6.3.5 The excess of lung cancer in the study area
The yearly average weighted indoor radon concentrations at Abbottabad, Mansehra,
Haripur, Battgram and Kohistan are 105 ± 17 3mBq , 112 ± 15 3mBq , 117 ±
16 3mBq , 111 ± 13 3mBq and 120 ± 16 3mBq respectively. Using these values in
the model in Fig.2.1, The excess of lung cancer per million per year (MPY) in all five
districts was calculated in Table 6.20.
76
Table 6.11: Weighted Indoor Radon concentrations )( 3mBq in the study area in the Spring season.
House No. Balakot Abbottabad Mansehra Haripur Battgram Kohistan 1. 70±11 49±8 54±7 56±16 50±7 55±8 2. 146±36 127±26 60±11 70±10 61±8 68±9 3. 148±38 122±23 64±13 80±11 70±10 150±42 4. 143±37 120±12 72±16 146±22 74±11 145±38 5. 123±22 66±8 84±17 100±17 80±12 70±11 6. 134±30 80±11 92±11 108±19 87±12 79±12 7. 142±32 115±17 100±12 110±20 90±14 85±13 8. 145±34 98±16 104±14 115±17 96±16 91±16 9. 154±41 100±15 110±15 123±19 102±17 99±15 10. 136±28 103±18 114±17 129±20 109±16 106±18 11. 135±30 108±21 122±22 134±24 116±18 114±20 12. 150±50 110±19 127±24 137±26 119±20 122±20 13. 126±24 111±20 133±25 139±26 122±21 130±26 14. 120±18 114±18 136±26 142±34 132±28 134±27 15. 138±28 116±21 139±30 143±36 138±30 138±30 16. 147±33 119±22 140±32 145±35 139±32 140±32 17. 110±16 121±23 142±33 147±36 141±38 144±38 18. 129±23 124±24 144±34 148±40 142±36 149±41 19. 90±12 126±17 147±32 151±42 146±39 152±40 20. 149±47 128±22 148±31 154±41 148±38 156±42
A.M 132 108 112 124 108 116 S.D 21 20 38 28 30 32
Range 70-150 49-128 54-148 56-154 50-148 55-156
Table 6.12: Weighted Indoor Radon concentrations )( 3mBq in the study area in the summer
season.
House No.
Balakot Abbottabad Mansehra Haripur Battgram Kohistan
1. 65±8 41±6 49±7 110±16 48±6 53±7 2. 78±12 59±7 57±9 111±17 60±7 70±9 3. 84±13 69±10 61±11 114±18 68±8 135±28 4. 99±14 78±11 69±10 117±17 73±10 80±14 5. 144±44 124±21 82±12 121±19 79±12 86±13 6. 143±41 123±26 89±11 122±20 81±13 91±16 7. 138±38 88±17 92±12 124±22 85±12 99±18 8. 139±37 99±16 101±13 128±26 89±15 104±19 9. 131±35 96±18 106±12 132±27 98±16 109±20 10. 132±28 100±19 109±14 133±28 104±17 112±21 11. 142±39 102±18 116±15 134±30 110±18 117±20 12. 129±24 106±14 119±14 138±32 114±20 120±22 13. 126±23 110±16 122±17 140±34 119±18 124±23 14. 127±22 113±19 125±18 150±38 121±20 129±25 15. 130±25 114±20 132±22 158±42 125±22 133±30 16. 119±20 118±21 136±28 167±48 126±24 138±32 17. 115±17 120±24 139±30 171±54 129±27 142±36 18. 109±17 121±20 140±32 174±55 132±30 144±38
77
19. 131±26 124±18 142±32 177±55 134±31 148±39 20. 111±16 126±21 144±33 182±60 135±34 150±42
A.M 120 102 106 140 102 114 S.D 22 23 30 23 26 27
Range 65-144 41-126 49-144 110-182 48-135 53-152
Table 6.13: Weighted indoor Radon concentrations )( 3mBq in the study area in the autumn
season.
House No.
Balakot Abbottabad Mansehra Haripur Battgram Kohistan
1. 119±19 98±10 108±12 51±7 102±17 108±19 2. 167±51 100±11 110±13 68±9 104±18 114±20 3. 128±27 104±12 112±14 75±11 106±16 118±19 4. 131±28 107±17 117±16 88±15 111±18 121±20 5. 133±29 111±14 120±18 96±16 113±17 125±22 6. 166±50 115±13 121±20 102±18 115±19 129±24 7. 136±32 119±22 124±21 108±19 117±20 131±25 8. 140±34 121±23 129±24 112±18 120±21 135±30 9. 161±52 123±24 133±28 115±19 123±22 138±33 10. 145±40 126±27 136±29 116±20 126±22 141±36 11. 147±41 130±32 142±32 120±21 128±24 146±34 12. 137±35 134±30 149±34 126±22 131±28 150±42 13. 151±42 137±30 154±39 130±26 133±30 153±41 14. 156±43 141±34 155±42 133±28 137±31 158±43 15. 162±49 144±28 159±45 136±27 141±36 161±46 16. 168±52 145±31 161±50 137±30 146±40 166±50 17. 170±56 147±34 165±52 139±32 151±44 176±51 18. 172±56 149±30 167±52 141±34 156±45 184±52 19. 150±42 152±32 170±54 144±33 165±45 188±50 20. 171±51 155±35 172±55 145±34 174±50 190±52
A.M 151 128 140 114 130 147 S.D 20 18 21 26 20 24
Range 119-172 98-155 108-172 51-145 102-174 108-190
Table 6.14: Weighted indoor Radon concentrations )( 3mBq in the study area in the winter season.
House No.
Balakot Abbottabad Mansehra Haripur Battgram Kohistan
1. 163±50 130±21 152±50 156±40 155±42 134±27 2. 171±56 132±23 154±49 157±41 156±44 138±28 3. 184±58 136±21 158±51 158±40 159±43 141±34 4. 187±57 141±26 160±52 159±42 161±45 147±33 5. 191±56 144±27 161±53 160±44 163±46 152±41 6. 196±60 148±34 162±52 162±47 164±45 158±43 7. 206±60 151±41 164±53 164±50 166±47 161±44 8. 210±62 154±42 166±54 166±51 167±49 165±45 9. 214±61 157±43 169±54 170±55 170±51 169±48 10. 217±62 160±20 170±55 171±54 172±52 172±50 11. 220±60 163±44 171±56 172±57 173±50 174±52
78
12. 217±59 164±42 173±58 173±56 176±54 178±55 13. 216±61 167±40 176±59 175±55 180±56 182±55 14. 219±60 170±39 179±58 178±57 183±57 187±56 15. 218±62 175±38 180±57 181±60 165±56 191±57 16. 219±63 177±41 181±59 182±61 158±60 199±56 17. 199±57 180±40 183±60 184±59 159±62 206±59 18. 209±60 187±38 186±58 188±62 162±60 216±60 19. 206±62 200±34 188±57 195±62 230±59 228±62 20. 211±63 210±32 220±62 236±64 157±62 254±64
A.M 204 162 172 174 170 178 S.D 16 21 15 18 16 24
Range 163-220 130-210 152-220 156-174 155-230 134-254
Table 6.15: Statistics for weighted annually averaged indoor radon concentrations
in )( 3mBq in the study area.
Balakot Abbottabad Mansehra Haripur Battgram Kohistan A.M 152 125 132 138 128 139 S.D 20 21 24 24 23 26
Range 65-220 41-210 49-220 56-236 50-230 55-254
Table 6.16: Weighted yearly indoor radon concentrations in n )( 3mBq in the study
area.
House No. Balakot Abbottabad Mansehra Haripur Battgram Kohistan 1. 112±18 84±12 87±13 90±13 83±12 93±14 2. 125±22 86±14 102±16 118±20 105±16 125±24 3. 130±24 87±16 112±20 94±14 108±18 138±32 4. 119±23 89±13 98±14 96±15 110±20 115±20 5. 110±19 92±12 101±16 99±16 116±22 98±14 6. 127±24 96±14 111±17 137±34 99±15 107±18 7. 106±26 99±15 106±18 120±23 101±14 109±18 8. 133±28 100±16 108±16 122±22 103±13 112±20 9. 134±30 102±17 94±14 109±18 104±19 114±22 10. 139±32 103±16 98±15 116±20 106±16 117±20 11. 144±34 105±16 117±20 113±18 109±18 100±14 12. 147±42 108±18 121±24 88±12 112±18 142±36 13. 132±30 110±20 120±22 119±22 114±18 124±26 14. 159±44 116±22 122±23 121±20 119±22 126±22 15. 160±48 121±20 119±20 124±26 123±20 130±28 16. 131±30 80±13 113±18 129±25 120±22 134±30 17. 163±50 123±24 104±16 130±28 129±26 136±32 18. 130±34 127±25 120±23 134±32 107±18 140±36 19. 133±32 132±30 147±44 139±36 115±20 149±40 20. 102±15 142±38 131±30 148±42 145±42 99±14
A.M 132 105 112 117 111 120 S.D 17 17 15 16 13 16
Range 110-163 84-142 87-147 88-148 83-145 93-149
79
Table 6.17: Arithmetic mean, maximum and minimum weighted indoor radon concentration
)( 3mBq for different floors for three districts of the study area weighted indoor radon
District name Mean Maximum Minimum Abbottabad Ground floor
First floor
125±22 116±16
210±32 184±34
41±6 36±5
Mansehra Ground floor
First floor
132±23 122±19
220±62 187±40
49±7 43±6
Haripur Ground floor
First floor
138±24 127±18
236±64 202±54
56±7 47±6
Table 6.18: Mean, maximum and minimum indoor radon concentration )( 3mBq in
different types of material made houses
District name Bricks Concrete Adobe Abbottabad
A.M Maximum Minimum
125±18 178±16 55±10
60±8 68±11 41±6
170±22 210±32 80±12
Mansehra A.M
Maximum Minimum
129±21 183±12 59±9
63±9 72±11 49±7
201±24 220±62 86±15
Haripur A.M
Maximum Minimum
135±17 188±13 61±11
66±9 77±12 51±7
210±27 236±64 96±19
Battgram A.M
Maximum Minimum
127±16 184±10 58±8
61±10 74±12 48±7
173±23 230±59 85±13
Kohistan A.M
Maximum Minimum
134±19 187±11 60±10
64±8 78±13 53±9
207±28 254±64 94±17
Table 6.19: Mean annual dose )(mSv from the weighted indoor radon concentration in the
study area
District name Radon concentration )( 3mBq Mean annual dose )(mSv
Abbottabad 125 3.54±0.59 Mansehra 132 3.74±0.71 Haripur 138 3.91±0.71 Battgram 128 3.62±0.82
80
Kohistan 139 3.94±0.73 Balakot 152 4.31±0.56
Table 6.20: Excess of lung cancer per million per year (MPY) from the indoor radon
level according to various agencies, in the study area.
Various agencies Excess of lung cancer per million per year (MPY) in the study area
Abbottabad Mansehra Haripur Battgram Kohistan
EPA(lower limit) 81 86 90 86 93
NCRP 1984 90 96 100 95 103
UNSCEAR(lower limit) 103 110 115 109 118
BEIR IV 160 171 178 169 183
EPA(upper limit) 186 198 207 197 213
UNSCEAR(upper limit) 210 224 234 222 240
Fig. 6.1: Frequency allocation of radon concentration in the spring water in Balakot.
0
1
2
3
4
5
6
7
8
9
10
2 4 6 8 10 12 14 16 18 20 22 240
1
2
3
4
5
6
7
8
9
10
xc=19.21933±0.00181
Fre
qu
ency
Radon concentration (kBq.m-3)
81
Fig. 6.2: Frequency allocation of radon concentration in the spring water (except
Mansehra) in the study area.
Fig. 6.3: Frequency allocation of radon concentration in the surface water in the study
area.
02
46
810
1214
1618
202224 0
1
2
3
4
5
6
7
8
9
Balakot
Abbottabad
Haripur
Battgram
Kohistan
Fre
qu
ency
Radon concentration(kBq.m -3)
0
5
10
15
2001234567891011121314
15
16
17
18
Balakot
Abbottabad
Mansehra
Haripur
Battgram
KohistanRadon concentration(kBq.m -3
)
Fre
qu
ency
82
Fig. 6.4: Frequency allocation of radon concentration in the bore water in the study area.
Fig. 6.5: Frequency allocation of radon concentration in all sources of water in the study
area.
0
5
10
15
20
25012345678910
11
12
13
14
15
16
Balakot
Abbottabad
Mansehra
Haripur
Battgram
Kohistan
Fre
qu
ency
Radon concentration(kBq.m -3)
02
46
8101214161820222426 0
2
4
6
8
10
12
14
16
18
20
Balakot
Abbottabad
Mansehra
Haripur
Battgram
Kohistan
Fre
qu
ency
Radon concentration(kBq.m -3)
83
Fig.6.6: Mean radon concentration )( 3mkBq in all sources of drinking water (except the
spring water from Mansehra) in the study area.
Fig. 6.7: Variation of radon concentration in spring water, along Balakot-Bagh (B-B) fault
line in the Balakot-section.
0
2
4
6
8
10
12
14
16
18
20
22
24
Abbottabad Mansehra Haripur Battgram Kohistan Balakot0
2
4
6
8
10
12
14
16
18
20
22
24
Rad
on
co
nce
ntr
atio
n (
kBq
.m-3)
Spring water Surface water Bore water Total
73.26 73.28 73.30 73.32 73.34 73.36 73.38
14
15
16
17
18
19
20
21
22
23
24
25
Rad
on
co
nce
ntr
atio
n(k
Bq
.m-3)
Longitude
0-10 km with73.26º as ref:(0 km) 0 km 10 km
84
Fig. 6.8: Mean annual dose estimated from all sources of drinking water (except the spring
water from Mansehra) in the study area.
Fig. 6.9: Frequency allocation of soil gas radon in the study area.
0.00
0.01
0.02
0.03
0.04
0.05
0.06
Balakot AbbottabadMansehra Haripur Battgram Kohistan
0.00
0.01
0.02
0.03
0.04
0.05
0.06
Do
se (
mS
v)
Spring water Surface water Bore water Total
02
46
810
1214
1618
2022 0
1
2
3
4
5
6
7
8
9
Balakot
Abbottabad
Haripur
Battgram
Kohistan
Fre
qu
ency
Radon concentration (kBq.m -3)
85
Fig. 6.10: Frequency allocation of soil gas radon in Balakot.
Fig. 6.11: Mean soil gas radon concentration )( 3mkBq in the study area.
0
1
2
3
4
5
2 4 6 8 10 12 14 16 18 20 220
1
2
3
4
5
Fre
qu
ency
Radon concentration (kBq.m-3)
0
2
4
6
8
10
12
14
16
Balakot Abbottabad Haripur Battgram Kohistan
0
2
4
6
8
10
12
14
16
Rad
on
co
nce
ntr
atio
n (
kBq
.m-3)
86
Fig. 6.12: Variation of soil gas radon concentration, along Balakot-Bagh (B-B) fault line, in
the Balakot-section.
Fig. 6.13: Frequency allocation of indoor radon concentration in Balakot.
73.28 73.30 73.32 73.34 73.36 73.38
8
10
12
14
16
18
20
22
Rad
on
co
nce
ntr
atio
n(k
Bq
.m-3)
Longitude
0
2
4
6
8
10
12
14
16
18
20
22
0 20 40 60 80 100 120 140 160 180 200 220 2400
2
4
6
8
10
12
14
16
18
20
22
Fre
qu
ency
Radon concentration (Bq.m-3)
0- 7.8 km with 73.28º ref: (0 km)0 km 7.8 km
87
Fig. 6.14: Frequency allocation of annual indoor radon concentration in the study area.
Fig. 6.15: Annual mean indoor radon concentrations )( 3mBq in the study area.
020
4060
80100
120140
160180
200220
240 0
2
4
6
8
10
12
14
16
18
20
22
Balakot
Abbottabad
Haripur
Battgram
Kohistan
Mansehra
Fre
qu
ency
Radon concentration (Bq.m -3)
0
10
20
30
40
50
60
70
80
90
100
110
120
130
140
150
160
170
180
Balakot Abbottabad Mansehra Haripur Battgram Kohistan0
10
20
30
40
50
60
70
80
90
100
110
120
130
140
150
160
170
180
Rad
on
co
nce
ntr
atio
n (
Bq
.m-3)
88
Fig. 6.16: Mean indoor radon concentration )( 3mBq in different seasons of the year.
Fig. 6.17: Mean indoor radon concentration )( 3mBq at ground and first floors in three
districts of the study area.
0
15
30
45
60
75
90
105
120
135
150
165
180
195
210
Balakot Abbottabad Mansehra Haripur Battgram Kohistan
0
15
30
45
60
75
90
105
120
135
150
165
180
195
210
225
Rad
on
co
nce
ntr
atio
n (
Bq
.m-3)
Spring Summer Autumn Winter
0
10
20
30
40
50
60
70
80
90
100
110
120
130
140
150
160
Abbottabad Mansehra Haripur0
10
20
30
40
50
60
70
80
90
100
110
120
130
140
150
160
170
Rad
on
co
nce
ntr
atio
n (
Bq
.m-3)
G.floor F.floor
89
Fig. 6.18: Mean indoor radon concentration )( 3mBq in different types of material made
houses in the study area.
Fig. 6.19: Seasonal correction factors for the study area.
0
20
40
60
80
100
120
140
160
180
200
220
240
Abbottabad Mansehra Haripur Battgram Kohistan
0
20
40
60
80
100
120
140
160
180
200
220
240
Rad
on
co
nce
ntr
atio
n (
Bq
.m-3)
Adobe Bricks Concrete
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
Balakot Abbottabad Mansehra Haripur Battgram Kohistan
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
Sea
son
al c
orr
ecti
on
fac
tor
Spring Summer Autumn Winter
90
Fig. 6.20: Comparison of yearly average measured indoor radon levels and seasonal average
indoor radon levels in the study area.
Fig. 6.21: Annual mean dose from indoor radon concentration in the study area.
0
10
20
30
40
50
60
70
80
90
100
110
120
130
140
150
160
170
180
Balakot Abbottabad Mansehra Haripur Battgram Kohistan
0
10
20
30
40
50
60
70
80
90
100
110
120
130
140
150
160
170
180
Rad
on
co
nce
ntr
atio
n (
Bq
.m-3)
Seasonal averged Yearly averaged
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
Balakot Abbottabad Mansehra Haripur Battgram Kohistan
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
Do
se (
mS
v)
91
CHAPTER 7
CONCLUSIONS AND FUTURE
RECOMMENDATIONS
7.1 Conclusions
From our observations, the measurements carried out for radon concentrations in all
water sources of the Hazara Division of N.W.F.P ( Khyber Pakhtun Khwa) Pakistan
are in the range of 1.7 to 25.4 3mkBq . The arithmetic means in radon concentrations
vary from 2.8 3mkBq to 20.98 3mkBq . The lower mean values correspond to surface
water source and the higher values to deep bore-hole water. From the statistical
analysis, about 40% of total samples have radon concentrations within the range
between (1.7 3mkBq and 9.0 3mkBq ), 14% of the samples have values lower than
11.0 3mkBq , 48% of the samples have values higher than 11.0 3mkBq and 52% of
the total samples show radon levels below 11.0 3mkBq )(MCL , recommended by
EPAUS and 48% above this level.
This study revealed the fact that higher radon concentration in the borehole
water at Jhangi Khoja (24.0 ± 1.6 3mkBq ) and in the spring water at Kakul (20.6 ±
2.6 3mkBq ) in Abbottabad as compared to that of other sites of the same area, are
directly connected to the geological characteristics of the region. Phosphates, being a
source of uranium, can emanate higher level of radon concentrations and are the
principal cause of high radon concentration in the water sources from this region.
The Ground Water Radon Concentrations (GWRC) in Hazara Division of
N.W.F.P (Khyber Pakhtun Khwa), were calculated for the first time, even for the first
time in Pakistan, or no published study that specifically investigated the GWRC in
Pakistan. Therefore the results of this study were compared with other studies carried
out in various parts of the world. In many cases the results were as good as while in
some other cases the results shows some deviation. The reasons for this deviation
were probably geology, environmental conditions and the systematic and random
errors in the experiments. However the survey of the area was carried out for the
92
establishment of a base line data which could further be exploited for the prediction of
earth-quake and other geophysical studies in future.
The bore hole water radon concentrations of this study were compared with
previous measurements from different countries in Table 6.8. This shows that the
radon levels are not either comparable or less than these countries.
All bore water samples were found to have higher mean radon concentration
than 11.0 3mkBq ( EPAUS limit) in the study area except Abbottabad where it was
lower than this limit. The mean radon concentrations in the spring water of Balakot,
Battgram and Mansehra were found higher than EPAUS recommended limit and
lower in Abbottabad and Haripur.
The mean radon concentrations in the surface water in the whole study area are within
the EPAUS limit. The average radon concentrations levels in spring and bore hole
waters of the whole study area are higher than EPAUS limit.
The average radon concentration in all types of drinking sources is
12.4 3mkBq in whole study area. This value is higher than the maximum
contamination level ( MCL ), recommended by EPAUS , however within the limit of
some European countries such as Romania Norway, Finland and Check Republic
[175], thus posing no threat to the health of local people. Even then it is suggested that
these drinking water sources must not be used before some remedial steps be taken for
the reduction of radon levels in it. The remedial steps include aeration of water and
filtration through charcoal filters etc.
From the soil gas radon measurements, it was observed that the mean radon
concentration in soil gas samples composed from the Hazara Division (study area)
was 7.6 ± 2.3 3mkBq . The maximum and minimum values of radon concentrations in
soil gas were 20.1 ± 2.5 3mkBq in Balakot and 2.3 ± 0.2 3mkBq in Abbottabad
respectively.
The higher radon concentrations in the spring water and in the soil at Balakot
in comparison to other parts of the study area reveal the fact that Balakot lies on the
fault line where the rocks under the soil have cracks which are more permeable to the
flow of radon gas in soil and in water. Subsequently, radon gas finds easy path to
flow from one part to the other part or it comes even more easily to the surface. The
other important reason may be the uranium deposits yet to be studied. The maximum
93
values of radon concentrations were found both in soil and in spring water at 73.34º E
longitude on Balakot-Bagh active fault line.
The annual average values of radon concentrations in indoor air samples
composed from Balakot, Abbottabad, Mansehra, Haripur, Battgram and Kohistan
districts were found as 152 ± 20 3mBq , 125 ± 21 3mBq , 132 ± 24 3mBq , 138 ±
24 3mBq , 128 ± 23 3mBq and 139 ± 26 3mBq respectively, from which the annual
mean doses were calculated as 4.30 ± 0.56 mSv , 3.54 ± 0.59 mSv , 3.74 ± 0.71 mSv ,
3.91 ± 0.71 mSv , 3.62 ± 0.82 mSv and 3.94 ± 0.73 mSv respectively.
The radon concentrations in indoor air samples composed from the Hazara
Division were found higher in winter than in spring, summer or in autumn. The lower
values of radon concentrations and doses were found in summer season in all districts
except Haripur where the lower values were found in autumn season. The reason for
the lower values may be the frequent flow of air at the elevated places as most of the
study area contains mountains at high elevation and the other reason may be the
height of atmospheric mixing layer during summer season.
The annual mean indoor radon concentration carried out on seasonal basis at
Balakot was found higher than 148 3mkBq ( EPAUS limit). The reasons for the high
indoor radon is the low ventilation, the type and nature of materials used in the
construction of houses, the geophysical structure of the area as it is lying on a
geological fault line. Moreover the area is rich with metamorphic and sedimentary
rocks, containing uranium-bearing minerals, a source of radon emanation [176].
Due to the same geology of the study area except Balakot, the variation in the
indoor radon values is because of the ventilation system, construction materials and
structures of houses in the study area. To diminish the indoor radon levels in the study
area, proper ventilation system and proper structure of houses may be devised in the
study area. There is no such upper limit defined for the indoor radon concentrations in
Pakistan so far. However, following the ICRP-65 recommendation, the obtained
indoor radon levels in the study area are within the acceptable limits except Balakot.
The arithmetic mean indoor radon in the whole study area is higher than average
radon concentration of the globe which is 40 3mBq .
As the indoor radon level depends on the season of the year consequently
seasonal correction factor must be used while calculating the annual mean radon
concentration in the case of radon measurement for a period less than a year. Seasonal
94
correction factor has been calculated which is in agreement with the other studies
conducted all over the world. The calculated annual mean effective dose was within
the permissible limits. Seasonally measured average values are higher as compared to
the values obtained from the year-long exposed CR-39 detectors. Long term exposure
of CR-39 detector reduces its efficiency to register tracks due to the formation of layer
of non radioactive dust over the surface of the detectors. The other reasons for the low
track density in the yearly exposed CR-39 detectors could be the heat and the
humidity in the air. Radon exhalation rate of soil and various building materials is
also responsible for the buildup of indoor radon concentration and their measurements
are of significant importance.
The accumulative annual doses received by the people of Balakot,
Abbottabad, Mansehra, Haripur, Battgram and Kohistan, from indoor radon levels and
from the water are 4.34 ± 0.56 mSv 3.56 ± 0.59 mSv , 3.78 ± 0.71 mSv , 3.93 ±
0.71 mSv , 3.65 ± 0.82 mSv , 3.98 ± 0.73 mSv in respectively. Doses received by the
inhabitant of the study area are within the permissible limit (3-10 mSv ) set by
International Council of Radiological Protection 65ICRP . The results obtained
from this study reveal the fact that the mean annual effective doses from water and
indoor air samples collected from Hazara region is 3.87 mSv which is within the
recommended action level of 65ICRP . Therefore, the people of this locality are
relatively safe from the health risks linked to radon and its decay products. However
some locations of the area need special attention to take the above mentioned
measures for the protection of health related risks from radon and its decay products.
The indoor radon concentrations were found higher on the ground floor than
on the first floor by almost 13%. The reasons are the subsidence of radon gas close to
ground surface and higher ventilation on the first floors. The indoor radon
concentrations were found higher in the adobe (mud made houses) than bricks- and
concrete-made houses, because of high porosity in the adobe or mud made houses.
7.2 Future recommendations
1. The present study does not cover the whole country, therefore it is recommended
that a similar systematic studies concerning measurement of indoor radon, soil
radon levels and radon concentration in the water sources be carried out.
95
2. Although the geology of the study area was taken into consideration for the present
study, but yet it needs a comprehensive study to know the formation and structure
of the underlying rocks.
3. For the validation of experimental observations, a suitable theoretical model must
be formulated.
4. The epidemiological studies of lung cancer should be carried out on country level
in order to calculate the proper risk coefficient in our environment.
5. The measurement of radon as tool for searching of uranium and other minerals as
well as for the geological mapping, field measurement must be carried out in order
to verify the laboratory measurements.
6. For radon levels in water, lithology and temporal variability must be taken into
account for the accurate measurement. Also the total dissolved solids in the water
be carefully found for better results.
7. The next similar sort of survey needs more instrumental arrangement.
8. The continuous monitoring is necessary for the prediction of geophysical event like
volcano eruption or tectonic eruption.
9. A well coordinated scientific approach is necessary from geology department,
meteorology department and environmental department to get better accuracy in
the measurement.
10. The lung cancer survey amongst the smokers and non smokers in the area is the
foremost requirement, for health caring and its correlation with radon
concentration in the area.
7.3 References
[1] Matiullah, A., Bashir, Yang, X. and Ahmed, A.. Recent studies on radon- a
measure of living standard. Nucl. Track and Radiat. Meas., 22, 395-398
(1993b).
[2] Durrani, S.A. and Ilic, R. Radon measurements by Etched Track Detectors.
World Scientific, London (1997).
[3] Davies, B.L. and Forward, J. Measurement of atmospheric radon in and out
door. Health Phys., 19, 136(1970).
96
[4] Khan. H.A. and Qureshi, A.A. Solid State Nuclear Track Detector: A
Useful Geological/Geophysical Tool. Nucl. Geophys, 8, 1-37 (1994).
[5] Evans, R.D. Engineering guide to the elementary behavior of radon
daughters. Health Phys., 38, 1173(1980).
[6] Saeed A. Durrani, Radomir Ilic. “Radon Measurements by Etched Track
Detectors. p (5)(1997).
[7] Matiullah. Radiation Physics. Allama Iqbal Open University Islamabad
(2000).
[8] Connell, C.P. Radon in water. Environment and Health, 3,30-35 (2005).
[9] Metter, J. Radon in context. Rad. Protect. Dosim., 42, 159-164(1992).
[10] Shafi-ur-Rehman. Radon measurements with CR-39 detector-
Implications for uranium ore analysis and risk assessment. Ph.D thesis
Department of Physics and Applied Mathematics PIEAS Islamabad
(2005).
[11] Field, R.W. A Review of Residential Radon Case-Control Epidemiologic
Studies Performed in the United State. Reviews on the Environmental
Health Preprint, 16, 151-167 (2001).
[12] Field, R.W., Steck, D.J., Smith, B.J., Brus, C.P., Fisher, E.L., Neuberger,
J.S., Platz, C.E., Robinson, R.A., Woolson, R.F. and Lynch, C.F.
Residential Radon Gas Exposure and Lung Cancer. The Iowa Radon
Lung Cancer Study. American Journal of Epidemiology, 151, 1091-11029
(2000).
[13] Pershagen, Liang, Z., Hrubec, Z., Svenson, C. and Boice, J.D. Residential
Radon Exposure and Lung Cancer in Sweden Women. Health Phys. 63,
179-186 (1992).
[14] ICRP-60. Recommendations of the International Commission on
Radiological Protection. ICRP Publication 60, Annals of the ICRP,
Pergamon Press, Oxford, UK (1990).
[15] Field, R.W. and Becker, K. Topics Under Debate. Doses Exposure to
Residential Radon Increase the Risk of Lung Cancer? Rad. Protect.
Dosim., 95, 75-81 (2001).
[16] National Research Committee on the Biological Effects of Ionizing
Radiation. The Health Effects of Radon and Other Internally Deposited
Alpha-emitters (BEIR-IV) (Washington, DC, USA ) pp. 440-418 (1987).
97
[17] NCRP. Evaluation of occupational and environmental exposure to radon
and radon daughters in the United States, report No.78 (1984).
[18] EPA. Radon Reduction Methods: a homeowner's Guide. US, EPA Report,
EPA-86-005, US Environmental Protection agency, Washington, DC
(1986).
[19] UNSCEAR. Sources and Effects of Ionizing Radiation. United Nations
Scientific Committee on the Effects of Atomic Radiation (UNSCEAR),
Report to the General Assembly (1988).
[20] Matiullah, Ahad, A., Rehman, S. and Mirza, M.L. Indoor radon levels and
lung cancer risk estimates in seven cities of the Bahawalpur Division,
Pakistan. Rad. Protect. Dosim., 269-276 (2003).
[21] Manual of RAD7 RAD H2O. DURRIDGE Company Inc. (2009).
[22] Hess, C.T., Frame. “ Radon Transferred from Drinking Water in to House
Air” Chapter 5 in Cothern and Rebers (1990).
[23] Caulfied, C. Multiple Exposures: Chronicles of the Radiation Age,
University of Chicago Press (1989).
[24] Crawford-Brown, D.J. “Analysis of the Health Risk from Ingested
Radon,” Chapter 2 in Cothern and Rebers (1990).
[25] Federal Register, EPA. “National Primary Drinking Water Regulations;
Radionuclides; Proposed Rule,” (40 CFR Parts 141 and 1420, 56(138):
33050-33127 (July 18, 1990).
[26] UNSCEAR, 2000. Sources and effects of ionizing radiation. United
Nations, New York (2000).
[27] Kristiansson K. and Malmqvist. Evidenec for non-diffusion transport of
222Rn in the ground and a new physical model for the transport.
Geophysics 47, 1444-1452 (1982).
[28] Mogro-Campero A., Fleischer R-L and Likes R. S. Changes in subsurface
radon concentration associated with earthquakes. J. Geophysical Res., 85,
3053-3057 (1980).
[29] Akerblom G. Ground radon monitoring procedures in Sweden.
Geoscientist 4, 21-27 (1993).
[30] Tanner, A.B. Radon migration in the ground: A review. In the Natural
Radiation Environment (eds. J. A. S. Adams and W. M. Lowder ),
university Press, Chicago, pp. 161-190 (1964).
98
[31] Shweikani, R., Giaddui, T. G. and Durrani S. A. The effect of soil
parameters on the radon concentration values in the environment.
Radiat. Meas., 25, 581-584 (1995).
[32] Jonsson, G., Persson M., Wikman H., Tell I., Osby community.
Investigation of soil radon in the community of Osby. Lund Institute of
Technology, Report LUTFD2/(TFKF- 3065 )/(1991) (1991) (In
Swedish).
[33] Tell, I., Bensryd I., Rylander L., Jonsson G. and Daniel E. Geochemistry
and ground permeability as determinants of indoor radon concentrations
in southern-most Sweden. Appl. Geochem. 9, 647-655 (1994).
[34] Banwell, G.M., Parizek, R.R. Helium-4 and Rn-222 concentrations in
groundwater and soil gas as indicator of zones of fracture concentration
in unexposed rock. J. Geophys. Res., 93 (B1), 355-366 (1988).
[35] Reddy, D.V., Sukhija, B.S., Nagabhushanam, P., Reddy, G.K., Kumar,
Devender, Lachassagne, P. Soil gas radon emanometry : a tool for
delineation of fractures for groundwater in granitic terrain. J. of Hydrol.,
329, 186-195 (2006).
[36] Ciotoli, G., Etiope, G., Guerra, M., Lombardi, S. The detection of
concealed faults in the OfantoBasin using the correalation between soil-
gas fracture survey. Tectonophy 301, 321-332 (1999).
[37] Berlo, K., Blundy, J., Turner S., Cashman, K., Hawkeshworth, C., Black,
S. Geochemical precursors to volcanic activity at Mount St. Helens, USA.
Science 306, 1167-1169 (2004).
[38] Musa, I.S.M. Radon in natural water. Doctoral thesis. Faculty of health
science Linkoping University, Sweden (2003).
[39] Kerry, A.L. Diffusion of radon through cracks in a concrete slab. Health
Phys., 43, 65-71 (1982).
[40] Nazaroff, W.W and Nero, A.V. Radon and its Decay Product in Indoor
Air. John Wiley and Sons, New York (1988).
[41] Rama, Moore, W.S. Mechanism of transport of U-Th series radioisotopes
from solid into ground water. Geochimica et Cosmochimica Acta 48,
395-399 (1984).
[42] Torgerson,T., Benoit, J., Mackie, D. Lithology control of groundwater
222Rn concentrations in fractured rock media. Isotopes of Noble Gases as
99
Tracer in Environmental Studies. In: Proceedings of a Consultants
Meeting on Isotopes of Noble Gases as Tracers in Environmental Studies
organized by the International Atomic Energy Agency and held in Vienna
from 29 May to 2 June. IAEA, Vienna, pp. 263-287 (1989).
[43] Davis, R.M., Watson jr., J.E. Influence of 226Ra concentration in
surroundings rock on 222Rn concentration in ground water. Health Phys.,
58 (3), 369-371 (1990).
[44] Gudzenko, V. Radon in subsurface water studies. Isotopes of Noble
Gases as Tracer in Environmental Studies. In: Proceedings of a
Consultants Meeting on Isotopes of Noble Gases as Tracers in
Environmental Studies organized by the International Atomic Energy
Agency and held in Vienna from 29 May to 2 June. IAEA, Vienna,
pp.249-261 (1992).
[45] Wannty, R.B., Lawrence, E. P., Gundersen, L. C. S. Theoretical model
for the flux of radon from rock to ground water. In: Gates, A. E.,
Gundersen, L. C. S. (Eds.), Geologic Controls of Radon, Special paper
271. Geological Society of America, pp. 73-78 (1992).
[46] Farai, I. P., Sanni, A .O. 222Rn in ground water in Nigeria: a survey.
Health Phys., 62 (1), 96-98, (1992).
[47] Dongarra, G., Hauser, S., Censi, P., Brai. M. Water chemistry, δ13C
values and 222Rn activity in groundwaters of Western Sicily. Nuclear
geophysics 9 (5), 461-470 (1995).
[48] Segovia, N., Mena, M., Monnin, M., Pena, P., Salazar, S., Seidel, J.L.,
Tamez, E. Fluctuations of ground water radon and chemical species in
basaltic aquifers. Radiat. Meas., 28 (1-6), 741-744 (1997).
[49] Choubey, V. M., Ramola, R. C. Correlation between geology and radon
levels in groundwater, soil and indoor air in Bhilangana valley, Garhwal
Himalaya, India. Environmental Geology 32, 258-262 (1997).
[50] Sun, H., Semkow,T. M. Mobilization of thorium, radium and radon
radionuclides in ground water by successive alpha-recoil. Journal of
Hydrology 205, 126-136 (1998).
[51] De Oliveira, J., Mazzilli, B., De Oliveria Sampa, M. H., Silva, B.
Seasonal variation of 226Ra and 222Rn in mineral spring waters of Aguas
da Prata, Brazil. Applied Radiation and Isotopes 49 (4), 423-427 (1998).
100
[52] Choubey, V. M ., Bartarya, S. K., Ramola, R. C. Radon in Himalaya,
springs: a geohydrological control. Environmental Geology 39 (6), 523-
530 (2000).
[53] Choubey, V.M., Bartarya, S. K., Saini, N. K., Ramola, R. C. Impact of
geohydrology and neotectonic activity on radon concentration in
groundwater of intermontane Doon Valley, Outer Himalaya, India.
Environmental Geology 40 (3), 257-266 (2001).
[54] Tricca, A., Porcelli, D., Wasserburg, G. J. Factors controlling the
groundwater transport of U, Th, Ra and Rn. Proceedings of Indian
Academy of Sciences (Earth Planet Science) 109 (1), 95-108 (2000).
[55] Kasztovszky, Z., Sajo-Bohus, L., Fazekas, B. parametric changes of
radon (222Rn) concentration in groundwater in Northeastern Hungary.
Journal of Environmental Radioactivity 49, 171-180 (2000).
[56] Virk, H.S., Walia, V., Bajwa, B. S. Radon monitoring in underground
water of Gurdaspur and Bathinda districts of Punjab, India. Indian
Journal of Pure and Applied Physics 39, 746-749 (2001).
[57] Labrecque, J. J., Cordoves, P. R., Rosales, P. A. Temporal variation
patterns of radon in minerals waters along the Cota Mil High, Caracas,
Venezuela. Journal of Radioanalytical and Nuclear Chemistry 253 (1),
41-46 (2002).
[58] Pryzlibski, T. A., Zebrowski, A. Origin of radon in medicinal waters of
Ladek Zdroj (Sudety Mountains, SW Poland). Journal of Environmental
Radioactivity 46 (1), 121-129 (1999).
[59] Pryzlibski, T. A. Size estimation and protection of the areas supplying
radon to ground water intakes. Archives of Environmental Protection 26
(1), 55-71 (2000).
[60] Pryzlibski, T. A., Zebrowski, A. Origin of radon in medicinal waters of
Swieradow Zdroj. Nukleonika 41 (4), 109-115 (1996).
[61] Pryzlibski, T. A., Mroczkowski, K., Zebrowski, A., Filibier, P. Radon-
222 in medicinal groundwaters of Zczawno Zdroj (Sudety Mountains,
SW Poland). Environmental Geology 40 (4/5), 429-439 (2001).
[62] Pryzlibski, T. A., Kozlowska, B., Dorda, J., Kielczawa B. Radon-222 and
226Ra concentrations in mineralized groundwaters of Gorzanow (Klodzko
101
Basin, Sudeten Moutains, SW Poland ). Journal of Radioanalytical and
Nuclear Chemistry 253 (1), 11-19 (2002a).
[63] Pryzlibski, T. A., Stasko, S., Szczepanowski, S., Modelska, Dorda, J.,
Kozlowska, B. Preliminary results of determinations of radon and radium
concentrations in surface and underground waters in the upper part of the
Kamienica River catchment basin (Snieznik Massif, Sudetes, SW
Poland). Przeglad Geologiczny 50 (5), 436-440, (in Polish) (2002b).
[64] Eisenohr, L., Surbeck, H. Radon as a natural tracer to study transport
processes in a karst system. An example in the Swiss Jura. Surface
Geoscienecs, C. R. Acad. Sci., Paris, t. 321, series II a, pp. 761-767
(1995).
[65] Cable, J.E., Burnett, W. C., Chanton, J.P., Weatherly, G. L. Estimating
groundwater discharge into the northeast Gulf of Mexico using radon-
222. Earth and Planetry Science Letters 144,591-604 (1996).
[66] Freyer, K., Treutler, H. C., Dehnert, J., Nestler, W. Determination of
222Rn in groundwater-recent applications for investigation of river bank
infiltration. In: Conference Proceedings of Second International
Conference on Isotopes. Millennium Sydney, 12-16 October, pp.10-15
(1992).
[67] Snow, D. D., Splading, R.F. Short-term aquifer residence times estimated
from 222Rn disequilibrium in artificially-recharged ground water. Journal
of Environmental Radioactivity 37 (3), 307-325 (1997).
[68] Kincaid, T. R. River water intrusion to the unconfined floridan aquifer.
Environmental and Engineering Geoscience IV (3), 361-374 (1998).
[69] Crandall, Ch.A., Katz, B.G., Hirten, J.J. Hydrochemical evidence for
mixing of river water and groundwater during high-flow conditions lower
Suwannee River Basin, Florida, USA. Hydrogeology Journal 7, 454-367
(1999).
[70] Hamada, H. Analysis of the interaction between surface water and
groundwater using radon-222. JARQ 33 (4), 261-265 (1999).
[71] Cook, P.G., Dighton, J.C., Love, A.J. Inferring groundwater flow in
fractured rock from dissolved radon. Ground water 37 (4), 606-610
(1999).
102
[72] Moise, T., Strainsky A., Kartz, A., Kolodny, Y. Ra isotopes and Rn in
brines and ground waters of the Jordan-Dead Sea Rift Valley:
enrichment, retardation, and mixing. Geochimica et Cosmochimica Acta
64 (14), 2371-2388 (2000).
[73] Karfi, U. radon in groundwater as a tracer to assess flow velocities: two
test cases from Israel. Environmental Geology 40 (3), 392-398 (2001).
[74] Schwatrz, M.C. Significant groundwater input to a coastal plain estuary:
assessment from excess radon. Estuarine Coastal and Shelf Science 56,
31-42 (2003).
[75] Al-Masri, M. S. and Blackburn, R. Radon-222 and related activities in
surface waters of the English Lake District. Appl. Radiat. Iso., 50, 1137–
1143 (1999).
[76] Loomis, D. P. Radon-222 concentration and aquifer lithology in North
Carolina. Groundwater Monit. Rev.7, 33–39 (1987).
[77] Choubey, V. M., Bartarya, S. K. and Ramola, R. C. Radon in ground
water of eastern Doon valley, Outer Himalaya. Radiat. Meas., 36, 401–
405 (2003).
[78] Gang, S., Boyou, Z., Xinming, W., Jingping, G., Daniel, C., John, B., Lee
S.C. . Indoor radon levels in selected hot spring hotels in Guangdong,
China. Science of the Total Environment 339 63– 70 (2005).
[79] Xinwei, L. Analysis of radon concentration in drinking water in Baoji
(China) and the associated health effects. Rad. Protect. Dosim., 121 (4):
452-455. doi: 10.1093/rpd/ncl048 (December 2006).
[80] Alirezazadeh, N. Radon concentrations in public water supplies in Tehran
and evaluation of radiation dose. Iran. J. Radiat. Res., 3 (2): 79-83 (2005).
[81] Yiğitoğlu, I., Öner, F., Yalim, H. A., Akkurt, A., Okur, A., Özkan, A.
Radon Concentrations in Water in the Region of Tokat City in Turkey.
Rad. Protect. Dosim., 145 (2-3) (2011)
[82] Amrani, D., Cherouati, D. E., Cherchali, M. E. H. Groundwater radon
measurements in Algeria. Journal of Environmental Radioactivity 51
173-180 (2000).
[83] Ramola, V.M., Choubey, M.S., Negi, Yogesh Prasad and Ganesh Prasad.
Radon occurrence in soil-gas and groundwater around an active landslide.
Radiat. Meas., 43, 98-101 (2008).
103
[84] Horvahth, AD., Bohus, L.O., Urbani, F. G., Marx, A., Piroh th, E.D.
Greaves Journal of Environmental Radioactivity 47, 127-133 (2000).
[85] Tadeuz Andrzej Przylibski, Kalina Mamont-Ciesla, Monika Kusyk, Jerzy
Dorda, Beata Kozlowska. Radon concentrations in groundwaters of the
Polish part of the sudety Mountains (SW Poland). Journal of
Environmental Radioactivity 75 193-209 (2004).
[86] Cosma, C., Moldovan, M., Tiberius, D., Kovacs T. Radon in water from
Transylvania (Romania). Radiat. Meas., doi: 10.1016/j.radmeas.
2008.05.001.
[87] Clavensjo, B. The Radon Book. The Swedish Council for Building
Research, Stockholm 1994.
[88] Erees, F. S., Aytas, S., Sac, M. M., Yener, G. and Salk, M. Radon
concentrations in thermal waters related to seismic events along faults in
the Denizli Basin, Western Turkey. Radiat. Meas., 42, 60–80 (2007).
[89] Schubert, M., Buerkin, W., Pena, P., Lopez, A.E., Balcazar, M. On-site
determination of the radon concentration in water samples; Methodical
background and results from laboratory studies and a field-scale test.
Radiat. Meas., 41, 492-497 (2006).
[90] Matiullah, Kudu, K., Majeed, A., Fujji, M. Radon- a measure of living
standard. Nucl. Tracks Radiat. Meas., 19, 371-374 (1991).
[91] IAEA Tec. Gamma-ray Surveys in uranium Exploration. Report. Series
No. 186, (1979).
[92] Mireles, F., Garica, M.L., Quirino, L.L., Davila, J.I., Pinedo, J.L., Rios,
C., Montero, M.E., Colmenero, L., Villalba, l. Radon survey related to
construction materials and soils in Zacatecas, Mexico using LR-115.
Radiat. Meas., (2008).
[93] Birchard, G. F. and Libby, W. F. Soil radon concentration changes
proceeding and following four magnitude 4.2-4.7 earthquakes on the San
Jacinato fault in the Southern California. J. Geophys. Res., 85, 3100-
3106 (1980).
[94] Jonsson, G. Radon gas- where from and what to do? Radiat. Meas., 25,
537-546 (1995).
[95] Keller, G and Folkerts, K.H. A study on indoor radon. In: Indoor Air:
Radon, Passive Smoking, Particulates and Housing Epidemiology. Ed by
104
Berglund, T Lindvall, J Sundell. Vol 2, Swedish Council for Building
Research, Stockholm, p 149 (1984).
[96] Khan, H. A., Afzal, M., Chaudhary, P., Mubarakmand, S., Nagi, F.I. and
Wahid, A. Some characteristics differences between the etch pits due to
radon and thoron alpha particles in CA80-15 and LR-115 cellulose nitrate
track detector Ins. Appl. Radiat. Isot., 28 (8), 727-731 (1977).
[97] Fleischer, R.L. Dislocation model for radon response to distant
earthquakes Geophys Res Lett., 8 477-480 (1981).
[98] Fleischer, R.L. and Turne, L.G. Correlations of radon and carbon isotopic
measurements with petroleum and natural gas at Cement, Oklahoma
Geophysics, 49 810-817 (1984).
[99] Khan. H.A., Tufail, M. Qureshi, A.A. Radon signals for earthquake
prediction and geological prospection. Journal of Islamic Academy of
Science, 3,(3), 229-231 (1990).
[100] Qureshi, A. A., Khan, H. A., Jafri, E. H., Tufail, M. and Matiullah.
Radon signals for geological explorations Int. J. Radiat. Appl. Instrum.,
Part D. Nucl. Tracks Radiat. Meas., 19 (1-4) 383-384 (1991).
[101] Khan, N.A., Mahmood, N.A. and Khaliq, M.A. Radioactive survey of
Kirana hills using solid state nuclear track detectors Nuclear Tracks 3
(4), 213-218 (1979).
[102] Rahman, S., Imtiaz, N., Faheem, M., Rehman, S. and Matiuallah.
Determination of 222U contents in ore samples using CR-39- based
radon dosimeter- disequilibrium case Radiat. Meas., 41 (4), 471-476
(2006a).
[103] Khan, H.A., Akber, R.A., Ahmed, I., Nadeem, K. and Beg, M.I. field
experience about the use of alpha sensitive plastic films for uranium
exploration Nucl. Instrum. Methods 173 (1), 191-196 (1980).
[104] Khan, H.A. and Haseebullah. Indoor radioactive pollution due to radon
and its daughters, Journal of Islamic Academy of Sciences 5(4), 249-255
(1993).
[105] Qureshi, A.A, Hussain, G., Mahmood, K., Baig, M.A.S. and Khan, H.A.
Use of alpha sensitive plastic film (ASPF) technique to locate the
remobilized uranium ore bodies in sandstones. Nucl. Tracks. Radiat.
Meas., 22, (1-4), 431-433 (1993).
105
[106] Qureshi, A.A., Kakar, D.M., Akram, M., Khattak, N.U., Tufail, M.,
Mehmood, K., Jamil, K. and Khan, H.A. Radon concentrations in coal
mines of Baluchistan, Pakistan. J of Environ. Radioact., 48, 203-209
(2000).
[107] Akber, R.A., Khan, H.A., Ahmed, I. and Jamil, K. Some important
considerations in the use of solid state nuclear track detectors for radon
gas concentration Measurements. Nucl. Tracks. Radiat. Meas., 173(1),
183-189 (1980).
[108] Mujahid, S.A., Hussain, S., Dogar, A.H. and Karim, S. Determination of
porosity of different materials by radon diffusion 40 (1), 106-109
(2005).
[109] Sial, M.A., Jamil, K., Sheikh, S.A., Khan, H.A., Molzahn, D., Vater, P.
and Brandt, R. The role of nuclear track filters in radon measurements.
Nucl. Tracks. Radiat. Meas., 12 (1-6), 705-708 (1986).
[110] Tufail, M., Matiullah., Ali, A., Orfi, S.D., Qureshi, A.A., Hussain, G and
Khan, H.A. Radon measurements in coal mines using polymeric nuclear
track detector. Nucl. Track.Radiat. Meas., 15 (1-4), 655-658 (1988a).
[111] Jamil, K., Rehman, F., Ali, S.A. and Khan, H.A. Determination of
equilibrium factor between radon and its progeny using surface barrier
detector for various shapes of passive radon dosimeters. Nucl. Instrum.
Method in phys. Res., A 388, (1-2), 267-272 (1997).
[112] Ahmed, S.M., Hussain, Z and Manzoor, F. Radon measurements in and
around a radiation research laboratory. Nucl. Track Radiat. Meas., 19
(1-4) 277-278 (1991).
[113] Tufail, M., Sikander, M.M., Mahmood,A.,Qureshi, A.A., Arafat, Y.and
Khan, H.A. Application of a" closed-can" technique for measuring
radon exhalation from mine samples of Punjab, Pakistan. J of Environ.
Radioact., 50 (3), 267-275 (2000).
[114] Jamil, K. and Ali, S. Estimation of radon concentrations in coal mines
using a hybrid technique calibration curve. J of Environ. Radioact., 54,
415-422 (2001).
[115] Rahman, S., Matiullah., Rehman, S. and Rehman, S. Studying 222Rn
exhalation rate from soil and sand samples using CR-39 Radiat. Meas.,
41, 708-713 (2006b).
106
[116] Rahman, S., Matiullah., Rehman, Z., Mati, N. and Ghauri, B.M.
Measurement of indoor radon levels in North West Frontier Province
and federally administered tribal areas-Pakistan during summer. Radiat.
Meas., 42 (2), 304-310 (2007a).
[117] Najeeb, R., Hussain, E. and Masood, U. Determination of radiological
doses of radon and natural radionuclides in the open environment of the
Lahore and Kasur districts, Pakistan. International journal of scientific
research 14, 11-17 (2005).
[118] Akram, M., Khattak, N.U., Iqbal, A., Qureshi,A.A., Ullah, K. and
Qureshi, I.E. measurements of radon concentration in dwellings of
Skardu city, Pakistan. Radiat. Meas., 40, 695-698 (2005).
[119] Iqbal, A., Baig, M. S., Akram, M., Qureshi, A.A. Measurement of radon
concentration using SSNDT in dwellings of Jhelum valley, Azad
Jammu and Kashmir, sub-Himalayas, northeast Pakistan. European
Journal Research 17 (3), 366-372 (2007a).
[120] Iqbal, A., Baig, M.S., Akram, M. Bashir, A. and Qureshi, A.A.
Measurements of radon concentration in dwellings of Muzafferabad
city, Azad Kashmir, northwest Himalayas Pakistan. Euro. J of Scientific
Res.,17 (3) 373-378 (2007b).
[121] Iqbal, A., Baig, M.S., Akram, M., Qureshi, R. K., Rahim, S. and Qureshi
A.A. Measurement of radon concentration using SSNTD in dwellings
of Rawalakot area, Azad Jammu and Kashmir, sub-Hamalayas,
Pakistan. Euro. J of Scientific Res., 17 (3), 392-398 (2007c).
[122] Tufail, M., Matiullah., Aziz, S., Ansari, f., Qureshi, A. A. and Khan,
H.A. Preliminary radon concentration-survey in some houses of
Islamabad. Nucl. Tracks. Radiat. Meas., 15 (1-4), 659-662 (1988b).
[123] Tufail, M., Khan, M.A., Ahmed, N., Khan, H.A. and Zafer, M.S.
Measurements of Radon Concentration in Some Cities of Pakistan.
Rad. Protect. Dosim., 40, 39-44 (1992).
[124] Tufail, M., Matiuallah,. Ahmed, N., Guo, S.L., Khan E.U. and Bashir,
A. Estimation of internal and external equivalent dose rate for dwellers
of Dera Ismail Khan, Pakistan. Nucl. Tracks. Radiat. Meas., 22 (1-4)
479-282 (1993).
107
[125] Khan, S.A., Ali, S., Tufail, M. and Qureshi, A.A. Radon concentration
levels in Fatima Jinnah Women University Pakistan. Radioprotection,
40 (1) 11-27 (2005).
[126] Rahman, S., Matiullah, Mati, N. and Ghauri, B.M. Seasonal indoor
radon concentration in the North West Frontier Province and federally
administered tribal areas-Pakistan. Radiat. Meas., 42 (10), 1715-1722
(2007b).
[127] Faheem, M., Mati, N. Matiullah. Seasonal variation in indoor radon
concentrations in dwellings in six districts of the Punjab province,
Pakistan. J. Radiol. Prot., 27, (4) 493-500 (2007).
[128] Miles, J. C. H. Temporal variation of radon levels in houses and
implications for radon measurement strategies. Rad. Prot. Dosim.,
93(4): 369-375 (2001).
[129] Gillmore, G. K., Phillips, P.S., Denman, A.R. The effects of geology and
the impact of seasonal correction factors on indoor radon levels: A case
study approach. Journal of environmental Radioactivity 84, 469-479
(2005).
[130] Friedmann, H. Final results of the Austrian Radon Project. Health Phys.,
89, 339-348 (2005).
[131] Karpinska, M., Mnich, Z., Kapala, J. Seasonal changes in radon
concentrations in buildings in the region of northeastern Poland. Journal
of Environmental Radioactivity 77, 101-109 (2004).
[132] Bossew, Peter., Lettner, Herbert. Investigations on indoor radon in
Austria, Part1: Seasonality of indoor radon concentration. Journal of
Environmental Radioactivity 98 , 329-345 (2007).
[133] Row, J.E., Kelly, M., Price., L.E. Weather system scale variation in
radon-222 concentration in indoor air. The Science of the Total
Environment 284, 157-166 (2002).
[134] Papaefthymious, H., Mavroudis, A., Kritidis, P. Indoor radon levels and
influencing factors in houses of Patras, Grecce. Journal of
Environmental Radioactivity 66, 247-260 (2003).
[135] De Francesco S., Pascale Tommasone F., Cuoco E., Tedesco D. Indoor
seasonal variability at different floors of buildings Radiation
measurement 45 928-934 (2010).
108
[136] U.S. Environmental protection Agency. A citizen's guide to radon.
Washington, DC: U.S. EPA; 402-K-00-006; (2004).
[137] Magalhaes, M.H., Amaral, E.C., Sachett, I., Rochedo, E.R. 222Rn in
Brazil: an outline of indoor and outdoor measurements. Journal of
Environmental Radioactivity 67 (2), 131-143 (2003).
[138] Bochicchio, F., Campos-venuti, G., Piermattei, S., Nuccetelli, C., Risica,
S., Tommasino, L., Torri, G., Magnoni, M., Agnesod, G., Sgorbati, G.,
Bonomi, M., Minach, L., Trotti, F., Malisan, M.R., Maggioio, S.,
Gaidolfi, L., Giannardi, C., Rongoni, A., Lombardi, M., Cherubini, G.,
D'Ostillio, S., Cristofaro, C., Pugliese, M., Martucci, V., Crispino, A.,
Cuzzocrea, P., Sansone Santamaria, A., Cappai, M. Annual average aand
seasonal variations of residential radon concentration for all the Italian
Regions. Radiat. Meas., 40, 686-694 (2005).
[139] Bossew, P., Letner, h. Investigation on indoor radon in Austria, Part1;
seasonality of indoor radon concentration. Journal of Environmental
Radioactivity 8 (3), 329-345 (2007).
[140] Moreno, V., Baixeras, C., Font, LI., Bach, J. Indoor radon levels and
their dynamics in relation with the geological characteristics of La
Garrotxa, Spain. Radiat. Meas., 43, 1532-1540 (2008).
[141] Hadad, Kamal., Doulatdar, R., Mehdizadeh, S. Indoor radon monitoring
in Northern Iran using passive and active measurements. Journal of
Environmental Radioactivity 85, 39-52 (2007).
[142] Qiuju, G., Boa, C., Quanfu, S. The adobe walls and floors have the
highest indoor radon concentrations. A pilot survey on indoor radon and
thoron progeny in Yangjiang, China. International Congress Series 276,
313-314 (2005).
[143] Kibria, S., Masud, B. tackling landslides during extension of KKH.
Pakistan Engineering Congress, 70th Annual Session Proceedings.
http://pecongress.org.pk/images/upload/books/Paper669.pdf. Accessed
on 14-10-2010.
[144] Qureshi, A. A., Khattak, N. U., Sardar, M., Tufail, M., Akram, M.,
Iqbal, T., and Khan, H. A. Determination of uranium contents in rock
samples from Kakul phosphate deposit, Abbotabad (Pakistan), using
fission-track technique. Radiat. Meas., 34 (1-6), 355-359 (2001).
109
[145] Naka, T., Hirayama, J., and Karim, T. Phosphorite-bearing Cambrian
Formations in the Himalayan Fold and Thrust Belt, Hazara Division,
Northern Pakistan. Proceedings of Geoscience Colloquium, Geoscience
Laboratory, Geological Survey of Pakistan, Islamabad, Vol. 11, pp.
149–180 (1995).
[146] Dellow, G.D., Ali, Q., Ali, S.M., Hussain, S., Khazai, B., Nisar, A.,
2006. Preliminary reconnaissance report for the Kashmir
Earthquake of 8 October 2005. 2006 NZSEE. Conference.
http://db.nzsee.org.nz/2006/Paper31.pdf. Accessed on 12-10-2010.
[147] Hussain, A., Pogue, K.R., DiPietro, J.A. Stratigraphy of the Precambrian
rocks of the Northwest Himalaya, Pakistan: Abstract, 4th Geological
Congress, Islamabad, Pakistan, p. 28 (2001).
[148] DiPietro, J.A., Ahmad, I., Hussain, A. Cenozoic kinematic history of the
Kohistan fault in the Pakistan Himalaya. Geological Society of America
Bulletin, 120, 1428-1440 (2008).
[149] Pogue, K.R., Hylland, M.D., Yeats, R.S. Stratigraphic and structural
framework of Himalayan foothills, northern Pakistan: 8th Himalayan,
Karakorum, Tibet Workshop, Abstract volume, Geologische
Bundesanstalt, Vienna, Austria, p. 73 (1993).
[150] Earthquake in Pakistan 2005. An assessment of environmental risks and
needs. IUCN Field Missions to NWFP and AJK November 19–26 and
December4–7,2005.
http://cmsdata.iucn.org/downloads/eq___risks_and_needs_assessment_r
eport.pdf. Accessed on 14-10-2010
[151] Hussain, A., Robert, S., Yeats, R.S., MonaLisa. Geological Setting of
the 8 October 2005 Kashmir earthquake. J Seismol (2009) 13:315–325
doi 10.1007/s10950-008-9101-7 (2008).
[152] Kaneda H, Nakata T, Tsutsumi H, Kondo H, Sugito N, Awata Y, Akhtar
SS, Majid A, Khattak W, Awan AA, Yeats RS, Hussain A, Ashraf M,
Wesnousky SG, Kausar AB. Surface rupture of the 2005 Kashmir,
Pakistan, earthquake, and its active tectonic implications: Bull Seismol
Soc Am 98: doi 10.1785/0120070073 (2008).
110
[153] Yasin, M., and Azam, M.A.M. Ground water appraisal of Haripur Plain,
District Abbottabad. Unpublished M.Sc. Thesis, University of Peshawar
(1976).
[154] Lucas H. F. Apparatus to determine thoron and radon centration in
mixture. U.S. Patent 4,975,574,901,204 (1990).
[155] Bochiccio F. and Risica S. Active radon and radon daughter monitors. In
Proc. Int. workshop on Radon Monitoring in Radioprotection,
Environmental Radioactivity and Earth Science (eds. L. Tommasino et
al.), Trieste, 1989, World Scientific, Singapore, pp. 110-121 (1990).
[156] Demel F. Radon activity measuring apparatus. Czeckoslovak (former)
Patent 8,604,867,880,615 (1988).
[157] Fukui M. Continuous monitoring of Rn-222 concentration in unconfined
water. J Hydrol., 82, 371-380 (1985).
[158] Navratil O. and Sury J. Determining volume activity of radon from soil
and atmospheric air. Czechoslovak (former) Patent 9,302,500,951,018
(1995).
[159] LeConte Cathey. Continuous radon monitoring. Rev. Sci. Inst., 49, 12
(1978).
[160] Melvin J. D., Shapiro M. H., Copping N. A. An automated radon-thoron
monitor for earthquakes prediction research. Nucl. Instr. Meth., 153,
239-251 (1978).
[161] Hussein, A.J. Natural Radioactivity in soil, Building Materials, Indoor
Radon Levels, Excess Cancer Risk in Jordan. Ph.D thesis, Centre for
Nuclear Studies, Quaid-i-Azam University Islamabad (1997).
[162] Matiullah, A., Bashir, Kudo, K. and Yang, X. Radon measurements in
some houses of Tsukuba science city-Japan. Nucl. Track and Radiat.
Meas., 22, 395-398 (1993).
[163] Howarth, C.B., and Miles, J.C.H. Results of the 2002 NRPB
international comparison of passive radon detectors. NRPB-W44,
Chilton (2002).
[164] Pinel, J., Fearn, T., Darby, S.C. and Miles, J. H .C. Seasonal correction
factors for indoor radon in the UK exposure in the dwellings in France.
Radiat. Protect. Dosim., 58(2), 127-132 (1995).
111
[165] N. Ali, E.U. Khan, P. Akhter, F. Khan, A. Waheed. Estimation of mean
annual effective dose through radon concentration in the water and
indoor air of Islamabad and Murree. Radiat. Protect. Dosim., 141 (2),
183-191 (2010).
[166] BEIR-VI, (Committee on Health Risks of Exposure to Radon –National
Research Council) Health effects of exposure to radon. National
Academy Press, Washington, DC. ISBN: 0-309-52374-5, 516 (1999).
[167] US EPA, 1991. National primary drinking water regulations:
radionuclides proposed (US EPA. Federal reg.56 33050).
[168] Khan, F., Ali, N., Khan, E. U., Khattak, N. U., I. A. Raja, M. U.
Rajput., Baloch, M. A. Study of indoor radon concentrations and
associated health risks in the five districts of Hazara division,
Pakistan. J. Environ. Monit., 14, 3015-3023 (2012).
[169] Roireau, N. and Zikovscki, L. Determination of radon in ground waters
of Quebec. J. Radioanal. Nucl. Chem. Lett., 137, 79-85 (1989).
[170] Cosma, C., Moldovan, M., Dicu, T., Kovacs, T. Radon in water from
Transylvania (Romania). Radiat. Meas., 43, 1423-1428 (2008).
[171] Vesterbacka, P., Makelainen, I., Arvela, H. Natural radioactivity in
drinking water in private wells in Finland. Rad. Protect. Dosim., 113(1),
223-232 (2005).
[172] Hopke, P. K. A layman’s guide to the indoor radon problem, in radon
and its decay products: occurrence, properties and health effects
American Chemical society, Washington, DC, 572 Symposium series.
331 (1987).
[173] Vitz, E. Towards a standard method for determining waterborne radon.
Health Phys., 60, 817-829 (1991).
[174] Homer, J.B. and Miles, J.C.H. The effect of heat and humidity before,
during after exposure on the response of PDAC (CR-39) to alpha
particles. Nucl. Tracks 12, 1-6, 133-136 (1986).
[175] Gustav Åkerblom. Radon Legislation and National Guidelines. ISSN
0282-4434 (Juli 1999).
112
[176] Khan, F., Ali, N., Khan, E. U., Khattak, N. U., Khan, K. Radon
Monitoring in water sources of Balakot and Mansehra cities lying on a
Geological Fault line. Rad. Protect. Dosim., 138(2), 174-179 (2010).