Radon: Health, Hazards, and your Home

Dr. Kent Scheller and Dr. William ElliottDepartment of Geology & Physics

September 24, 2015

Introduction

Naturally Occuring Radiation

Terrestrial: U, Th, K in soilCosmogenic: cosmic raysIndustrial: mining, drillingAgricultural: uptake of elements in plantsDomestic: building materials, medical treatments

So, what is radon and where does it come from? U-234 U-238

Pa-234

Th-230 Th-234

Uranium Decay ChainRa-226

Rn-222

Po-210 Po-214 Po-218

Bi-210 Bi-214

Pb-206 Pb-210 Pb-214

4.5x109 y4x105 y

26.8 min3.05 min

3.82 d

1600 y

7.7x104 y

24 d

1.2 min

19.9 min

1.6x10-4 s

5 d

22.3 y

138 d

Radon—Much is known…

Radon Danger in the United States

Figure from EPA (2014).

Radon Danger in Indiana

Maps from Indiana State Department of Health (2015).

How does it affect you?

Figure from EPA (2014).

Since Radon is a colorless, odorless gas, it enters your home with no notice through your bottom floor. When inhaled, Radon enters your lungs and continues its radioactive decay chain subjecting lung cells to ionizing radiation.

*Radon is thought to cause about 21,000 lung cancer deaths per year, according to EPA’s 2003 Assessment of Risks of Radon in Homes. The numbers of unintentional injury-related deaths in the home from other causes are estimates from the 2000–2008 National Vital Statistics System presented in: Mack KA, Rose A, Mickalide AD, Ballesteros M. Fatal unintentional injuries in the home in the U.S., 2000–2008: American Journal of Preventive Medicine 2013;44(3):239–246.

Safe levels?

Table from Indiana State Department of Health (2013).

Radon Research at USI

In an effort to look for coal-bed methane on the USI campus, drilling took place from which 750 ft of cores were obtained.

Geologic map of the study area with the location of USI 1-32 as indicated by a star. In addition, Series of Pennsylvanian units are used to produce this geologic map (modified from King and Beikman, 1974). Dotted line demarcates the southern extent of Wisconsinan glaciation in this area, although significant loess drapes hilltops north of the Ohio River and south of the glacial limit.

What we found…

Stratigraphic column, age designation, and gamma-ray log for USI 1-32 used in this study. Identification of stratigraphic units and nomenclature based primarily from Shaver et al. (1986). Additional sources were used to resolve shale units, such as Mecca and Logan Quarry, and the various named coal seams (Zangerl and Richardson, 1963; Heckel et al., 1998; Droste and Horowitz, 1998). The five cored intervals collected from USI 1-32 are also identified, as well as well cuttings collected during coring.

Methods of Core Study– Geochemical Analysis

• Analyze the core samples from depths indicating high radioactivity for its elemental composition.

– Gamma (γ) Ray Spectroscopy• Use the γ-ray signature of the radioactive decays in the cores to

identify their source and relative quantity.

Using the two methods in tandem, we are able to unambiguously identify the sources of radiation and ultimately the source of radon in our cores.

Cores from USI 1-32

Geochemical Data

• Covariance of uranium, chromium, and vanadium associated with elevated organic carbon content (5 to 15 wt. %) and phosphate.

• Deposition related to elevated organic productivity or Ocean Anoxic Event (?)

Gamma Ray Spectra

Geology and Radon Migration

Levels of radon measured in residential settings from 2007 to 2013 in Vanderburgh County, Indiana. This radon data is plotted on a bedrock geologic map; the black shale overlying the Danville coal corresponds to the contact between the Dugger and Shelburn formations. Likewise, the black shale above the Ditney Coal is exposed stratigraphically just above the boundary between the Shelburn and Patoka formations. Additionally, the boundary of Ohio River floodplain and terrace deposits, as well as the northern margin of outwash deposits are highlighted on this map. Geologic contacts from Cable and Wolf (1977); Hatch and Affolter (2002); and Moore et al. (2007).

Implications• So what?

– Awareness• Remodeling

• Home purchase

– Testing• Local Contractors

– http://www.in.gov/isdh/files/1_Radon_Mitigator_List_-_for_website_and_public.pdf

– Online Testing Services

– Remediation• Local Contractors

– http://www.in.gov/isdh/files/1_Radon_Mitigator_List_-_for_website_and_public.pdf

• Simple Process

The problem:

The solution:

www.connecticutradon.com

www.unce.unr.edu

Conclusions• What did we learn?

– Radon gas is here

– Radon gas can cause cancer

– Radon gas can be measured

– Radon gas can be remediated

• But, only if you know it’s there….

Acknowledgments• Dr. Paul Doss and Dr.

Norman King

• Jeff Turner, Indiana State Department of Health

• Christopher Smith, Weatherford Labs in Houston, Texas

• Undergraduate Students: Clinton Broach, Aaron Feldhaus, & Ryan Voegrel

Why it’s important….

Questions?