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Wireless Communications & Health in the USA: issues, regulatory policies & research International Scientific Workshop on Health Aspects of Mobile Telephony, Brussels 29-30 October 2001 Members of US delegation Robert Cleveland, Ph.D. Senior Scientist, Federal Communications Commission C.K. Chou, Ph.D. Chief EME Scientist, Motorola Florida Research Laboratories Jerrold Bushberg, Ph.D. Clinical Professor, School of Medicine, Univ. of California, Davis Joe Elder, Ph.D. Director, Biological Research, Motorola Florida Research Laboratories James Lin, Ph.D. Professor, Elec.Engineering & Bioengineering, Univ. of Illinois, Chicago Russell Owen, Ph.D. Chief, Radiation Biology Branch, Food & Drug Admin. (CDRH) Topics to be addressed Public concern Regulations and jurisdiction Policy development Research Consumer outreach & education Risk assessment Health/safety issues have been raised for both phones and base stations Some sources of controversy Media reports Conflicting scientific reports Lack of confidence in RF standards Fear of “radiation” Differences in RF safety standards between countries Issues in experimental science RF dosimetry is complicated Many effects not repeatable but still cause concern Inadequate attention to engineering and biological details in experiments Positive effects that are later proven to be artifacts Concern in USA over potential RF health effects from mobile phones US General Accounting Office (GAO) asked by US Congress to prepare report on mobile phone safety Final GAO report (May 2001) concluded: No evidence of adverse health effects to date However cannot conclude no risk No definitive answers likely for some time FCC & FDA provide better information to consumers Measurement standard needed for phone SAR US Federal Communications Commission & US Food and Drug Administration FCC & FDA share regulatory jurisdiction for wireless communications safety FCC adopted revised RF exposure guidelines in 1996 apply to both fixed & mobile/portable transmitters FDA jurisdiction emphasizes radiation emissions from consumer/industrial products (ionizing, RF, UV, etc) Center for Devices & Radiological Health (CDRH) FDA RF standard: microwave ovens FCC, FDA & other US health/regulatory agencies are members of an inter-agency RF working group RF exposure standards International Commission on Non-Ionizing Radiation Protection (ICNIRP) Institute of Electrical and Electronics Engineers (IEEE) National Council on Radiation Protection and Measurements (NCRP) FCC (USA) guidelines based on NCRP & IEEE Also, US military uses IEEE standard FCC regulatory policy FCC not a health/safety agency but must comply with National Environmental Policy Act FCC relies on expert organizations & agencies for guidance on health/safety issues Guidelines adopted after extensive public comment Guidelines endorsed by US Government health/safety agencies: FDA, EPA, NIOSH, OSHA Rule citations: Title 47, US Code of Federal Regulations, Sections 1.1307(b), 1.1310, 2.1091, 2.1093 Exposure guidelines based on Specific Absorption Rate (SAR) SAR = rate energy absorbed per unit mass Units: watts/kg (W/kg) or milliwatts/gm (mW/g) IEEE, NCRP & ICNIRP all identify 4 W/kg as threshold for potentially harmful effects Limits for localized exposure, field strength & power density all traceable to this value Scientific basis for standards Science-based standards (all effects considered) Thermal effects Shocks, burns, and resulting tissue damage Non-thermal effects not found hazardous Threshold for potential harm: 4 W/kg (whole-body) Based on behavioral changes in animals Basis for IEEE, ICNIRP, NCRP exposure limits Table 1. FCC Limits for Maximum Permissible Exposure (MPE) (A) Limits for Occupational/Controlled Exposure __________________________________________________________________________ Frequency Electric Magnetic Power Averaging Range Field Strength Field Strength Density Time 2 (MHz) (V/m) (A/m) (mW/cm ) (minutes) __________________________________________________________________________ 0.3-3.0 614 1.63 (100)* 6 2 3.0-30 1842/f 4.89/f (900/f )* 6 30-300 61.4 0.163 1.0 6 300-1500 --f/300 6 1500-100,000 --5 6 ___________________________________________________________________________ (B) Limits for General Population/Uncontrolled Exposure ___________________________________________________________________________ Frequency Electric Magnetic Power Averaging Range Field Strength Field Strength Density Time 2 (MHz) (V/m) (A/m) (mW/cm ) (minutes) ___________________________________________________________________________ 0.3-1.34 614 1.63 (100)* 30 2 1.34-30 824/f 2.19/f (180/f )* 30 30-300 27.5 0.073 0.2 30 300-1500 --f/1500 30 1500-100,000 --1.0 30 ___________________________________________________________________________ f = frequency in MHz * = Plane-wave equivalent power density RF exposure standards for mobile telephones USA: FCC uses IEEE limit of 1.6 W/kg averaged over one gram of tissue Other countries using 1.6 W/kg include Canada, Korea & Australia Some countries (example China) considering other Europe: many countries adopting ICNIRP limit of 2.0 W/kg averaged over 10 grams of tissue ICNIRP limit less conservative than IEEE limit FCC regulations RF guidelines: 300 kHz-100 GHz Technical documents providing techniques for evaluating exposure OET Bulletin 65 + Supplements A, B & C Mobile phone approval requires SAR test data FCC will conduct compliance testing of mobile phones FCC and FDA staff working with IEEE committees developing guidelines for exposure & measurements Example, IEEE SCC34: developing recommended practice for measuring SAR from mobile phones FDA activities Radiation Control for Health & Safety Act of 1968 Applies to radiation-emitting electronic products Long term animal studies Work with National Toxicology Program & other groups Exposure assessment & test method development Cellular and animal experiments on enzyme activity Assessments and education FDA cooperative research program Cooperative Research and Development Agreement (CRADA) with the Cellular Telecommunications & Internet Association FDA provides scientific and technical oversight Three parts Micronucleus assay Epidemiology Other topics Resolving scientific questions about RF safety No single piece of research can definitely answer any scientific question Conclusions must be based on consensus drawn from cumulative evidence Reports of effects must be subjected to appropriate scientific scrutiny Development of science-based policy Must be based on scientific data Empirical evidence evaluated Sources of uncertainty identified Establish level of protection Exposure assessment and evaluation of measurement capabilities necessary What can be provided by the scientific process? Scientific approach prescriptive & predictive power Establish effects which cause identifiable health problems Dose response relations established Threshold values established Where possible identify mechanism of action Science-based research needed for making policy decisions Goal is replication and consistency Need critical number of scientists working on a large number of projects Government and independent support and commitment needed Industrial sector can complement Government involvement important for general public acceptance Science-based approach requires multiple projects Biological systems and organisms are complex Responses may vary for “similar” exposures Reproducibility & independently repeated studies required for evidence and statistical significance Repeatability and confirmation fundamental to the scientific approach Research to date on mobile telephony and health Approximately 300 studies, almost 200 completed Vast majority show no effect - no consistent positive result suggests an adverse health effect Need to understand basic mechanism causing any biological response to determine relevance to wireless technologies Only RF effects in two main areas established: Thermal effects of RF energy Neurostimulation by RF fields and currents Studies conducted in the US About 300 studies worldwide related to mobile telephony 80 studies ongoing or completed in US All studies contribute to the total picture and should not be considered in isolation Current major studies include: Studies at Washington University Battelle-Pacific National Laboratory FDA/CTIA CRADA Animal studies planned by US NTP (NIEHS) US Air Force research Recent expert scientific reviews World Health Organization International Commission on Non-Ionizing Radiation Protection European Commission Expert Group Royal Society of Canada Expert Group U.K. National Radiological Protection Board U.K. Independent Expert Group on Mobile Phones French Expert Report Spanish Expert Review Common conclusion: No credible evidence that RF exposures within accepted limits cause adverse health effects How is public opinion formed? Media reports Corrections to erroneous reports usually not subsequently reported Statements from “experts” Rumors and “word of mouth” Note: members of the general public rarely read scientific journals Sources for consumer outreach & education Government agencies (FCC, FDA) Industry (manufacturers, service providers) Many now provide SAR & standards information Trade associations (CTIA in USA) CTIA-certified phones must provide SAR information International organizations (WHO, ICNIRP) Scientific organizations (BEMS) Miscellaneous Web sites FCC Internet Site for RF Safety: www.fcc.gov/oet/rfsafety Frequently asked questions (“FAQs”) Texts of FCC decisions FCC publications on RF safety SAR values for mobile phones available Links to other Web sites Also, dedicated telephone line for information: +1-202-418-2464 FDA Web site: www.fda.gov/cdrh/phones Joint FDA/FCC Web site on mobile phone safety Under Development Public perception of risk Fact: In general people & the press focus on bad news more than good news Proposition: A single study showing an association between RF & an adverse health effect will not be easily offset by numerous studies failing to show an association Public perception of risk Consequence: As more research is performed it is more likely that there will be increased public concern, even if the majority of the studies fail to show any adverse health effects Conclusion: In the Short Term, risk assessment studies tend to increase perceived risk - this does not mean don't do them, but rather be prepared for the result Risk communication & educating the general public Simplify technical information Build trust in information sources Independence & timeliness of information is important Use appropriate analogies for risk Explain the scientific process Listen to what the public is saying & honestly address their concerns What can we conclude? RF biological research & dosimetry are complicated Establishing health/safety standards based on research is even more complicated & requires judgement & assumptions in lieu of complete knowledge In future: we will know more about what we question today but...we may also have new questions While this is the very nature of scientific research…it can be, in fact, very counterintuitive to the general public