Is Your Cell Phone Killing You?
Transcript of Is Your Cell Phone Killing You?
Is Your Cell Phone Is Your Cell Phone Killing You?Killing You?
Mobile Communications FairMobile Communications FairSponsored by Tech-ConnectSponsored by Tech-Connect
Presented by Tim Weber, PRA InternationalPresented by Tim Weber, PRA InternationalFebruary 23, 2010February 23, 2010
OutlineOutline
Background/IntroductionBackground/Introduction DefinitionsDefinitions Commonly studied health risksCommonly studied health risks What does science tell us?What does science tell us? Do cell phones really cause cancer?Do cell phones really cause cancer? What are the important conclusions?What are the important conclusions? Concerns about kids & phonesConcerns about kids & phones What is the future of the research?What is the future of the research? Q&AQ&A
Speaker’s BackgroundSpeaker’s Background
Tim Weber, PhDTim Weber, PhD• Bachelor’s in Chemical Engineering, Bucknell Bachelor’s in Chemical Engineering, Bucknell
UniversityUniversity• Doctorate in Chemical Engineering, University Doctorate in Chemical Engineering, University
of Virginiaof Virginia• Doctoral research on lovastatin, active Doctoral research on lovastatin, active
ingredient of Mevacoringredient of Mevacor®®; led to US patent; led to US patent• 12+ years with PRA International, a contract 12+ years with PRA International, a contract
research organizationresearch organization• Contributed to the approval of at least 5 drug Contributed to the approval of at least 5 drug
products currently marketed in the USproducts currently marketed in the US
Introduction/HistoryIntroduction/History
11stst generation (1G) generation (1G)• Analog phones; early 80’s; 450 & 900 MHzAnalog phones; early 80’s; 450 & 900 MHz
22ndnd generation (2G) generation (2G)• Digital (Global System for Mobile Digital (Global System for Mobile
Communication, or GSM); early 90’s; 900 & Communication, or GSM); early 90’s; 900 & 1800 Mhz1800 Mhz
33rdrd generation (3G) generation (3G)• Universal Mobile Telecommunication System Universal Mobile Telecommunication System
(UMTS); ca. 2003; 1900-2200 MHz(UMTS); ca. 2003; 1900-2200 MHz 44thth generation (4G) generation (4G)
• Still relatively new; frequency 2000-8000 MHzStill relatively new; frequency 2000-8000 MHz
Introduction/History, cont’d.Introduction/History, cont’d.
Each successive generation has Each successive generation has operated at a higher frequency: operated at a higher frequency: more apps = more powermore apps = more power
Usage increasing…and fast!Usage increasing…and fast!• 5% in 1998 5% in 1998 67% (4.6 billion) in 2009 67% (4.6 billion) in 200911
• Almost half of US children aged 8-12 are Almost half of US children aged 8-12 are cell phone userscell phone users
1 International Telecommunications Union. The World in 2009: ICT Facts and Figures. http://www.itu.int/ITU-D/ict/material/Telecom09_flyer.pdf
Some Basic DefinitionsSome Basic Definitions CTIA – International Association for the CTIA – International Association for the
Wireless Telecommunications Industry (Wireless Telecommunications Industry (www.ctia.orgwww.ctia.org) )
RF-EMR (RF) – Radio frequency RF-EMR (RF) – Radio frequency electromagnetic radiationelectromagnetic radiation
SAR – Specific absorption rate; how much SAR – Specific absorption rate; how much RF is absorbed into the body when RF is absorbed into the body when exposed to a radiation source, such as a exposed to a radiation source, such as a mobile device (measured in W/kg; ≤1.6 in mobile device (measured in W/kg; ≤1.6 in US; ≤2.0 in EU)US; ≤2.0 in EU)
Meta-analysis – analyzes multiple studies Meta-analysis – analyzes multiple studies with similar research objectiveswith similar research objectives
Definitions (2) - Odds RatioDefinitions (2) - Odds Ratio 50/100 men and 25/100 women are color 50/100 men and 25/100 women are color
blindblind• p1 = probability of a man being color blindp1 = probability of a man being color blind• p2 = probability of a woman being color blindp2 = probability of a woman being color blind
Odds Ratio: (p1/(1-p1))/(p2/(1-p2))Odds Ratio: (p1/(1-p1))/(p2/(1-p2)) In our example:In our example:
• (0.5/(1-0.5))/(0.25/(1-0.25))(0.5/(1-0.5))/(0.25/(1-0.25))• (0.5/0.5)/(0.25/0.75)(0.5/0.5)/(0.25/0.75)• (1/(1/3)) = 3(1/(1/3)) = 3
Conclusion: A man is 3 times more likely Conclusion: A man is 3 times more likely than a woman to be color blindthan a woman to be color blind
Definitions (3) Relative RiskDefinitions (3) Relative Risk
Same groups of men & womenSame groups of men & women Relative Risk: p1/p2Relative Risk: p1/p2 In our example:In our example:
• 0.5/0.25 = 20.5/0.25 = 2 Conclusion: The risk of a man being Conclusion: The risk of a man being
color blind is twice that of a womancolor blind is twice that of a woman
Case-Control StudiesCase-Control Studies
Used widely in epidemiological Used widely in epidemiological studiesstudies• Compare individuals who have a certain Compare individuals who have a certain
condition (cases) with those who do not condition (cases) with those who do not (controls)(controls)
• Controls should be matched for age, Controls should be matched for age, gender, and ethnicitygender, and ethnicity
• Can suggest, but cannot prove, Can suggest, but cannot prove, causality of a particular condition (e.g., causality of a particular condition (e.g., tobacco consumption and lung cancer)tobacco consumption and lung cancer)
Case-Control Studies, cont’d.Case-Control Studies, cont’d.
To date, most widely used tool for To date, most widely used tool for studying health risks of cell phone studying health risks of cell phone usageusage• Cell phone usage has mushroomed in Cell phone usage has mushroomed in
just the last decade or sojust the last decade or so• Relies on memory and anecdotal Relies on memory and anecdotal
evidence of past usageevidence of past usage• Typically in-person or telephone Typically in-person or telephone
interviewsinterviews
Commonly Studied Health Risks Commonly Studied Health Risks
Possible association with cancerPossible association with cancer Source of distraction while drivingSource of distraction while driving Poor fertility/DNA damage in malesPoor fertility/DNA damage in males Miscarriage/morbidity in unborn childrenMiscarriage/morbidity in unborn children CNS (migraine, vertigo, ALS, MS, epilepsy)CNS (migraine, vertigo, ALS, MS, epilepsy) Interference with pacemakers, hearing Interference with pacemakers, hearing
aids, and defibrillatorsaids, and defibrillators Exposure to radiation from cell phone Exposure to radiation from cell phone
towerstowers
What Does Science Tell Us?What Does Science Tell Us?
RF-EMR is similar in energy to AM/FM RF-EMR is similar in energy to AM/FM radio waves, microwaves, and radio waves, microwaves, and infrared heat lampsinfrared heat lamps• non-ionizing radiationnon-ionizing radiation• not capable of breaking molecular bonds not capable of breaking molecular bonds
(e.g., DNA)(e.g., DNA)• does not enter body tissuesdoes not enter body tissues• same type of radiation used in MRI same type of radiation used in MRI
technologytechnology
Do Cell Phones Cause Cancer?Do Cell Phones Cause Cancer? Searching on “cell phones cancer” returns almost Searching on “cell phones cancer” returns almost
24 million Google hits and 300 PubMed articles24 million Google hits and 300 PubMed articles The American Cancer Society, FDA, National The American Cancer Society, FDA, National
Cancer Institute, FCC, CDC, and National Cancer Institute, FCC, CDC, and National Toxicology Program (NTP) have all issued Toxicology Program (NTP) have all issued statements saying that there is, at present, no statements saying that there is, at present, no definite link, but that more research is neededdefinite link, but that more research is needed
The EPA, NTP, and International Agency for The EPA, NTP, and International Agency for Research on Cancer (IARC) have not classified Research on Cancer (IARC) have not classified cell phones as to their carcinogenicitycell phones as to their carcinogenicity
What Types of Tumors?What Types of Tumors? Astrocytoma – brain cancer (star-shaped tumor)Astrocytoma – brain cancer (star-shaped tumor) Acoustic neuroma – benign tumor that affects the Acoustic neuroma – benign tumor that affects the
88thth cranial nerve (runs from brain to inner ear) cranial nerve (runs from brain to inner ear) Glioma – brain cancer that forms in the glial cells Glioma – brain cancer that forms in the glial cells
(surround and support nerve cells)(surround and support nerve cells) Meningioma – slow-growing tumor that forms in Meningioma – slow-growing tumor that forms in
the meninges (tissue surrounding brain and the meninges (tissue surrounding brain and spinal cord)spinal cord)
Testicular cancerTesticular cancer Non-Hodgkin’s lymphomaNon-Hodgkin’s lymphoma Salivary gland tumorsSalivary gland tumors Pituitary tumorsPituitary tumors
What Does the Literature Tell Us?What Does the Literature Tell Us?
Could do a daylong Mobile Fair just on this Could do a daylong Mobile Fair just on this topictopic
Slides that follow are meant to be Slides that follow are meant to be representative, not exhaustiverepresentative, not exhaustive
Other sources of info:Other sources of info:• American Cancer Society (American Cancer Society (www.cancer.orgwww.cancer.org) ) • National Cancer Institute (National Cancer Institute (www.cancer.govwww.cancer.gov) ) • CNET (CNET (www.cnet.comwww.cnet.com) ) • WebMD (WebMD (www.webmd.comwww.webmd.com))• Environmental Working Group (SAR values; Environmental Working Group (SAR values;
http://http://www.ewg.org/cellphonewww.ewg.org/cellphone-radiation/-radiation/))
Kristiansen, et al., Kristiansen, et al., BioelectromagneticsBioelectromagnetics (2009) (2009)
Results from 2006 Danish phone survey Results from 2006 Danish phone survey (N=1004)(N=1004)
28% worried about exposure to mobile 28% worried about exposure to mobile phone radiation (82% worried about phone radiation (82% worried about pollution)pollution)
49% say mortality risk on par with dying 49% say mortality risk on par with dying from a lightning strike; 7% on par with from a lightning strike; 7% on par with dying from smoking-induced lung cancerdying from smoking-induced lung cancer
Overall conclusion: most aren’t terribly Overall conclusion: most aren’t terribly concerned, but a minority is very concerned, but a minority is very concernedconcerned
Hardell & Carlberg, Hardell & Carlberg, International International Journal of OncologyJournal of Oncology (2009) (2009)
Case-control study 1997-2003Case-control study 1997-2003 2159 cases with brain tumors; 2162 2159 cases with brain tumors; 2162
population-based controlspopulation-based controls Ipsilateral astrocytoma and acoustic Ipsilateral astrocytoma and acoustic
neuroma after >10 years of use: OR neuroma after >10 years of use: OR = 3.3 and 3.0, respectively= 3.3 and 3.0, respectively
Highest risk among users whose first Highest risk among users whose first use was before age 20use was before age 20
Ahlbom, et al., Ahlbom, et al., EpidemiologyEpidemiology (2009) (2009)
Meta-analysis of 16 studies published Meta-analysis of 16 studies published 1999-20081999-2008
Methodological deficiencies of case-control Methodological deficiencies of case-control studies: selective nonresponse and studies: selective nonresponse and exposure misclassificationexposure misclassification
No increased risk of fast-growing tumors No increased risk of fast-growing tumors with ~10 years of cell phone use; more with ~10 years of cell phone use; more time needed to decide on slow-growingtime needed to decide on slow-growing
Maximum risk vs. detectable risk: should Maximum risk vs. detectable risk: should be a detectable signal by now if there be a detectable signal by now if there really is an increased riskreally is an increased risk
Rothman, Rothman, EpidemiologyEpidemiology (2009) (2009)
Tumors of interest are all rare typesTumors of interest are all rare types Insufficient exposure of users (long Insufficient exposure of users (long
induction times for tumors)induction times for tumors) Effects, if any, resulting in today’s Effects, if any, resulting in today’s
tumors likely from 1G and 2G phonestumors likely from 1G and 2G phones Accurate exposure assessment Accurate exposure assessment
difficult if not impossibledifficult if not impossible Case-control studies are subject to Case-control studies are subject to
recall biasrecall bias
What Does the Literature Tell Us?What Does the Literature Tell Us?
Majority of authors find no definitive linkMajority of authors find no definitive link Why does it seem to be Hardell vs. everyone Why does it seem to be Hardell vs. everyone
else?else? Shortcomings of current study designs & researchShortcomings of current study designs & research Some increases in overall brain cancer rates: Some increases in overall brain cancer rates:
better tests; earlier diagnoses; MRI/CT scansbetter tests; earlier diagnoses; MRI/CT scans Most evidence supporting a link to cancer comes Most evidence supporting a link to cancer comes
from EU-based studies where the maximum SAR from EU-based studies where the maximum SAR is higher than the USis higher than the US
INTERPHONE vs. International EMF Collaborative; INTERPHONE vs. International EMF Collaborative; not sure either of these has much meritnot sure either of these has much merit
Concerns about Kids & PhonesConcerns about Kids & Phones
Seem to be sound scientific reasons Seem to be sound scientific reasons to monitor usage of cell phones by to monitor usage of cell phones by kids:kids:• Nervous systems are still developingNervous systems are still developing• Brain tissue is more conductive than Brain tissue is more conductive than
adultsadults• More RF penetration due to smaller head More RF penetration due to smaller head
sizesize• Longer lifetime of exposure (first use Longer lifetime of exposure (first use
typically well before 10)typically well before 10)
Concerns about Kids (2)Concerns about Kids (2)
Estimation of the absorption of electromagnetic radiation from a cell phone based on age (frequency GSM 900 Mhz) (on the right, a scale showing the specific absorption rate at different depths, in W/kg) (Gandhi et al. IEEE Trans Microwave Theor Tech. 1996;44:1884-1897. ©1996 IEEE).
Figure from Han, et al., in Surgical Neurology 72 (2009) 216-222
What Is the Future of Research?What Is the Future of Research?
Better methods to measure and quantify Better methods to measure and quantify RF exposure (e.g., is a 10-minute call the RF exposure (e.g., is a 10-minute call the same as 10, 1-minute calls?)same as 10, 1-minute calls?)
Better models to estimate SAR away from Better models to estimate SAR away from the surfacethe surface
Identifying the cellular target of RF-EMRIdentifying the cellular target of RF-EMR Well-designed prospective cohort studies Well-designed prospective cohort studies
to evaluate cancer, CNS, reproduction, to evaluate cancer, CNS, reproduction, interference, etc.interference, etc.
Future Research (2)Future Research (2) Longer-term (15-20 years) case-control Longer-term (15-20 years) case-control
studiesstudies• most tumors take at least 10 years to developmost tumors take at least 10 years to develop
More research involving childrenMore research involving children By constantly developing higher-frequency By constantly developing higher-frequency
devices and using them more often, are devices and using them more often, are we escalating the risk faster than our we escalating the risk faster than our bodies can adjust?bodies can adjust?
Is texting the answer?Is texting the answer? Topics that haven’t even arisen yet Topics that haven’t even arisen yet
(second-hand radiation, anyone?)(second-hand radiation, anyone?)
Questions?Questions?
If you have questions, please don’t If you have questions, please don’t hesitate to contact me:hesitate to contact me:
Tim WeberTim [email protected]@PRAINTL.com
434-951-3212 (W)434-951-3212 (W)434-882-1940 (M)434-882-1940 (M)