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Current State of Knowledge about Electromagnetic Fields, Mobile Telephony and Health

Current State of Knowledge about Electromagnetic Fields, Mobile Telephony and Health

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Current State of Knowledge about Electromagnetic Fields, Mobile Telephony and Health

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  1. Current State of Knowledge about Electromagnetic Fields, Mobile Telephony and Health b.veyret@piom.u-bordeaux.fr Brussels, October 2001 EU-Japan-Korea-USA

  2. Frequency Spectrum 1 fm 1 GHz Brussels, October 2001 EU-Japan-Korea-USA

  3. Scientific approaches epidemiology humans animals cells Biological models Dosimetry Foundations Brussels, October 2001 EU-Japan-Korea-USA

  4. Health effect Biological effect Biochemical changes Biophysical intercation Brussels, October 2001 EU-Japan-Korea-USA

  5. Definition of SAR • SAR: specific absorption rate • SAR: rate of power absorption per unit of mass (watt / kilogramme; W/kg) • SAR is proportional to the temperature increase in the tissue Brussels, October 2001 EU-Japan-Korea-USA

  6. Thermal versus nonthermal • A ‘ thermal ’ biological effect is due to an increase in temperature at high SAR level • A ‘ nonthermal ’ effect occurs at low SAR level with a negligible input of power andno temperature increase • At medium SAR level the thermoregulation system prevents any temperature increase. ‘Athermal’ effects might occur due to stress. Brussels, October 2001 EU-Japan-Korea-USA

  7. Mobile telephones / base stations • Handsets - medium-level: up to 1/2 of guidelines- head-only exposure (so far)- SAR < 1.6-2 W/kg • Base stations - low-level: often < guidelines / 10,000 - whole-body exposure- SAR < 0.08 W/kg Brussels, October 2001 EU-Japan-Korea-USA

  8. Sources of scientific information • Peer-reviewed articles • Review articles • Reports (COST 244bis, Stewart ’s group, Zmirou ’s group, FDA, etc.) • Monographs (WHO, IARC, ICNIRP, etc.) Brussels, October 2001 EU-Japan-Korea-USA

  9. WHO database • Cancer relevant or related • completed ongoing totalepidemiology 8 18 26bioassays 6 8 14sensitized in vivo11 7 18acute in vivo22 5 27in vitro50 26 76Total 97 64 161 Brussels, October 2001 EU-Japan-Korea-USA

  10. WHO database • Non cancer • completed ongoing totalepidemiology 4 0 4human 45 21 66acute in vivo32 10 42in vitro15 10 25Total 96 41 137 Brussels, October 2001 EU-Japan-Korea-USA

  11. Epidemiology 1/2 • Study of the link between exposure and disease • mobile telephony: 3 case-control (Hardell 1999, Muscat 2000, Inskip 2001) and 2 cohort studies (Morgan 2000, Johanson 2001) • Main focus on brain cancer • Negative resultsbut link with laterality of use? • Limited by exposure assessment, evolving technology, short latency, etc. Brussels, October 2001 EU-Japan-Korea-USA

  12. Epidemiology 2/2 • Ongoing large case-control questionnaire studyled by IARC and funded in part by EU: Interphone • Head and neck tumours: glioma, meningioma, acoustic neurinoma, and parotid gland malignant tumours • 14 countries involved • Preliminary exposure assessment study in progress • Results expected by 2004? Brussels, October 2001 EU-Japan-Korea-USA

  13. Human laboratory studies • Cognition • Sleep • EEG • Blood pressure • Subjective symptoms • etc. Brussels, October 2001 EU-Japan-Korea-USA

  14. Cognition • Thuroczy 1997: cerebral circulatory disturbances, alteration of electrical activity • Freude 1998, 2000: Slow brain-wave potential influenced in visual monitoring tasks • Preece 1999: decrease in choice reaction times • Koivisto 2000: decreased response times • Lee 2001: mobile telephone users performed better in 1 out of 3 attention tests Brussels, October 2001 EU-Japan-Korea-USA

  15. Sleep • Mann & Röschke 1996: alterations in sleep onset latency, REM sleep, EEG during REM sleep • Wagner 1998: no alterations in sleep onset latency, REM sleep duration • Borbély 1999: decreased waking duration,EEG increase in non-REM sleep • Huber 2000: EEG increase in non-REM sleep Brussels, October 2001 EU-Japan-Korea-USA

  16. EEG • Reiser 1995: increase power 9.75-32 Hz • Röschke & Mann 1997: No effects • Hietanen 2000: statistically significant changes • De Seze 2000: alterations of EEG patterns • Krause 2000: Increase power in 8-10 Hz during memory task Brussels, October 2001 EU-Japan-Korea-USA

  17. Blood pressure • Braune 1998: increasedresting blood pressure • Lindholm,ongoing: no effects so far Brussels, October 2001 EU-Japan-Korea-USA

  18. Subjective symptoms • Oftedal, 2000; Sandström, 2001: warmth on the ear, headaches, etc. • Koivisto, 2001: no association between symptoms and exposure (healthy subjects) • Hietanen, 2001: no association between symptoms and exposure (hypersensitive subjects) Brussels, October 2001 EU-Japan-Korea-USA

  19. Animal models: in vivo Brussels, October 2001 EU-Japan-Korea-USA

  20. 3 types of exposure systems Brussels, October 2001 EU-Japan-Korea-USA

  21. Head-only exposure Loop antenna Brussels, October 2001 EU-Japan-Korea-USA

  22. Whole-body exposure system ITIS Brussels, October 2001 EU-Japan-Korea-USA

  23. Head-mainly exposure Brussels, October 2001 EU-Japan-Korea-USA

  24. Cancer in vivo studies • Bioassays • Grafted tumours • Sensitized models (carcinogens, ionizing radiation, genetic factors, etc.) • Genotoxicity Brussels, October 2001 EU-Japan-Korea-USA

  25. 2-year bioassays • Adey 1999: 836.55 MHz, TDMA 2000: 836.55 MHz, FMFisher 344 rats: No Effects • Zook 2000: 850 MHz, MiRS - TDMA850 MHz, FMSprague Dawley rats: No Effects Brussels, October 2001 EU-Japan-Korea-USA

  26. 2-year bioassays: ongoing • Roti Roti • 847.74 MHz, CDMA, 835.62 MHz, FM • Fisher 344 rats • Anderson • 1616 MHz, IRIDIUM, Fisher 344 rats • Dasenbrock • GSM-900, and 1800, B6C3F1 mice • Dotti • GSM-900, and 1800; Wistar rats • NIEHS, planned Brussels, October 2001 EU-Japan-Korea-USA

  27. Grafted tumours • Salford, 1993: 915-MHz, CW and AM, up to 8.3 W/kg, Fisher rats, glioma injection in brain:No effect on tumour growth • Roti Roti, 1999: 835.62-MHz FM or 847.74-MHz CDMA, 0.75 W/kg, glioma injection in brain:No effect on tumour growth Brussels, October 2001 EU-Japan-Korea-USA

  28. Chemically-induced tumours • Chagnaud, 1999: GSM-900, whole-body, BP- induced tumors: No effects on tumour latency or survival nor on lymphocyte subpopulations, • Shirai, 1999: local 923-MHz exposure, rat liver carcinogenesis chemically-induced :No effects. • Adey, 1999, 2000: ENU-initiated brain tumors in Fisher 344 rats; 836.55MHz, TDMA or FM:No effects on tumour growth. • Shirai:ENU-initiated brain tumors, 1.5 GHz ongoing Brussels, October 2001 EU-Japan-Korea-USA

  29. DMBA -induced tumors • Rat model of mammary tumors:- Anane 1999, 2000: GSM-900 and -1800, whole-body, several SAR levels- Bartsch 2001: GSM-900, whole-body, low SAR level: 0.1 W/kg3 one-year studies:No delay in onset of malignant tumors • Perform A: Hruby, GSM-900, several SAR levels: ongoing • China; Chiang, ongoing Brussels, October 2001 EU-Japan-Korea-USA

  30. Appearance of first malignant tumour 1 .8 Sham DMBA GSM-1800 60 rats/group .6 1.4 W/kg .4 P = 0.22 .2 0 0 20 40 60 80 100 Time (days) Brussels, October 2001 EU-Japan-Korea-USA

  31. DNA fragmentation • Increased DNA fragmentation reported by Lai and Singh 1995, 1996, (comet assay) in rats exposed to 2.45-GHz pulsed fields • Failure of a replication study by Roti Roti 1999 • Negative results in an analog mobile-phone  study by Tice & Hook, 1999 • Negative results in a GSM-900 study by Lagroye and Anane, 2000 Brussels, October 2001 EU-Japan-Korea-USA

  32. B T Transgenic mice • Repacholi 1997 • Large effect but: • Exposure system? • Transgenic model? • Interpretation? • Replication • Australia • Italy Exposed Sham Brussels, October 2001 EU-Japan-Korea-USA

  33. Non-cancer in vivo studies • Behaviour (only at high SAR levels) • Hearing • Memory and learning • Blood Brain Barrier • Heat Shock Proteins • etc. Brussels, October 2001 EU-Japan-Korea-USA

  34. Hearing • Work of the Marino and Aran groups have yielded negative results on alterations of the functions of the inner ear • More research in progress within theEuropean GUARD programme Brussels, October 2001 EU-Japan-Korea-USA

  35. Memory and learning • Lai 1994:decreased learning in 12-arm maze, whole-body exposure to pulsed fields • Sienkiewicz 2000, GSM 900, whole-body, low SAR: negative • Dubreuil 2001: GSM 900, head only: negative • Replication by Cobb, ongoing: negative so far • Thuroczy, Sienkiewicz & Cassel : ongoing • Long-term memory, Nagawa: negative Brussels, October 2001 EU-Japan-Korea-USA

  36. Blood-brain-barrier BBB • Persson & Salford 1997:increased BBB permeability at low SAR levels • Fritze 1997: reversible effect seen only at high SAR • Tsurita 2000:no effect even at high SAR • Aubineau 2001: effect at 2 W/kg and inflammation of the dura mater. Ongoing search for threshold • Mason: replication of Persson & Salford ’s data: ongoing Brussels, October 2001 EU-Japan-Korea-USA

  37. Heat Shock Proteins HSP • de Pomerai 2000 • Transgenicnematodes- 700 MHz CW- Low SAR • Increase in HSPexpression Brussels, October 2001 EU-Japan-Korea-USA

  38. Cellular models: in vitro Brussels, October 2001 EU-Japan-Korea-USA

  39. In vitro: exposure systems Petri dishes Brussels, October 2001 EU-Japan-Korea-USA

  40. In-vitro studies (1/3) • Completed Ongoing TotalCancer 38 23 61 Non-Cancer 36 19 55 • Genotoxicity and DNA breaksMicronuclei, SCE, chromosome aberrationsObe, Maes & Verschaeve, Eberle, Tice,Roti Roti, Meltz, Scarfi, etc. • Proliferation and transformationFitzner, Kwee, Wobus, Lagroye, Bersani, etc. Brussels, October 2001 EU-Japan-Korea-USA

  41. In vitro studies (2/3) • Gene expression- Leszczynski, ongoing: increased expression of hsp27 at 2 W/kg • Enzyme activity: ODC- Byus, 1998, Litovitz,1997- replication by Billaudel & Naraala • Signal transduction- Byus, 1984 Brussels, October 2001 EU-Japan-Korea-USA

  42. In vitro studies (3/3) • Role of free radicals-Juutilainen • Calcium- Bawin, Blackman, Meyer • Role of co-factors (UV, etc.)?? Brussels, October 2001 EU-Japan-Korea-USA

  43. Mechanisms • Only well-established mechanisms is heating • Others are being explored and tested in the laboratory: • Spatial and temporal temperature gradients • Membrane rectification • Absorption by magnetite • Radical pair mechanisms • etc. Brussels, October 2001 EU-Japan-Korea-USA

  44. Conclusions • 200 studies related to mobile telephony have been completed / 100 more are ongoing. • No constant reported positive finding at nonthermal levels • Some key large-scale studies are in progress and their results should provide a solid database for risk assessment • Known thermal effects are portable to 3G • Assessment will have to be provided for both mobile telephones and base stations Brussels, October 2001 EU-Japan-Korea-USA