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Bernard Veyret PIOM Laboratory College of Chemistry and Physics, Bordeaux b.veyret@enscpb.fr

Biological Effects in the Microwave, Thz, and Infrared Regions. Bernard Veyret PIOM Laboratory College of Chemistry and Physics, Bordeaux b.veyret@enscpb.fr. Frequency Spectrum. static. RF. 1 fm. 1 GHz. THz gap. 50/60 Hz. History. Microwaves (radars, hyperthermia)

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Bernard Veyret PIOM Laboratory College of Chemistry and Physics, Bordeaux b.veyret@enscpb.fr

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  1. Biological Effects in the Microwave, Thz, and Infrared Regions Bernard Veyret PIOM Laboratory College of Chemistry and Physics, Bordeaux b.veyret@enscpb.fr Capri, THz, 2002

  2. Frequency Spectrum static RF 1 fm 1 GHz THz gap 50/60 Hz Capri, THz, 2002

  3. History • Microwaves (radars, hyperthermia) • Mobile telephony (analog, TDAM, CDMA) • Wireless communications Capri, THz, 2002

  4. Health effect Biological effect Biochemical changes Biophysical intercation Capri, THz, 2002

  5. Scientific approaches epidemiology humans animals cells Biological models Dosimetry Foundations Capri, THz, 2002

  6. Sources of information • Databases • WHO EMF project (www.who.int/peh-emf/), IEEE, Information Venture, etc. • Reports, Reviews • ICNIRP, WHO, … • ‘ McKinlay ’, ‘ Stewart ’, ‘ Zmirou ’ ‘ Health Canada ’, etc. • Scientific societies • BEMS, EBEA, URSI, etc. Capri, THz, 2002

  7. Sources of information • Peer-reviewed articles Out of 31,049 refs, only one on THz! Capri, THz, 2002

  8. WHO databasemobile telephony signals • 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 Capri, THz, 2002

  9. WHO databasemobile telephony signals • Non cancer • completed ongoing totalepidemiology 4 0 4human 45 21 66acute in vivo32 10 42in vitro15 10 25Total 96 41 137 Capri, THz, 2002

  10. WHO database • mm waves: 12 references (< 94 GHz) • THz and IR: 0 reference Capri, THz, 2002

  11. Centimetre waves (l > 3 cm) • Mechanism: heating • Metric: SAR (W/kg) • ICNIRP basic restriction: 2 W/kg (10 g) • Dosimetry (dielectric properties, numerical simulations, etc.):satisfactory • Epidemiology: • Cancer: unconclusive, large study in progress • Symptoms: unconclusive Capri, THz, 2002

  12. cm waves • Humans • Minor alterations of sleep, EEG, etc. • No evidence of hypersensitivity Capri, THz, 2002

  13. Whole-body exposure system mice ITIS Capri, THz, 2002

  14. Head-only exposure Loop antenna Capri, THz, 2002

  15. Head-mainly exposure Capri, THz, 2002

  16. cm waves • Animals • Cancer: negative • Blood-brain-barrier: some evidence > 1 W/kg Capri, THz, 2002

  17. In vitro: exposure systems 1800 MHz Kuster et al. Petri dishes Capri, THz, 2002

  18. cm waves • Cells • Proliferation: negative • Genotoxicity: negative • Heat shock proteins: positive? Capri, THz, 2002

  19. Millimetre waves (3 cm > l > 3 mm) • Basic restriction: irradiance E ICNIRP: 10 W/m2 • Absorption by the skin • Initial article from Germany: Grundler, W. and Keilmann, F. (1978) Nonthermal effects of millimeter microwaves on yeast growth. Z Naturforsch [C], 33, 15-22. Capri, THz, 2002

  20. mm waves in the FSU • Basic research and medical applications • Betski ’s school: 10 mW/cm2 non resonant • Sitko ’s school: µW/cm2 resonant • Skin disorders, gastric ulcers, heart disease, and cancer • Today, most of the Russian scientists work in Europe and USA Capri, THz, 2002

  21. mm waves • Main review: Pakhomov, Bioelectromagnetics, 19, 393-413 (1998) • Main research groups: Temple University, Philadelphia, and Brooks AF base, TX, USA, • Research activity likely to increase in the coming years (R-Lan, radar, etc.) Capri, THz, 2002

  22. Main target: skin Capri, THz, 2002

  23. mm waves: cancer • Carcinogenesis 2001 Oct;22(10):1701-8 • Lack of effect of 94 GHz radio frequency radiation exposure in an animal model of skin carcinogenesis • Mason et al. Brooks, TX, USA • 3.33 W/m2, 10 sec, twice a wk for 12 wks Capri, THz, 2002

  24. Spectrum of water THz IR Capri, THz, 2002

  25. THz (3 mm > l > 15 µm) • ICNIRP: 1000 W/m2 (1,041 µm to 1 mm,10 s to 8 h) based on thermal effects on the cornea Capri, THz, 2002

  26. Far infrared (15 µm > l > 3 µm) • Few studies besides the thermal effect on the cornea Capri, THz, 2002

  27. Mechanisms • Very low energy of the microwave photon 1 GHz = 4 x 10-6 eV 1 THz = 4 x 10-3 eV kT = 3 x 10-2 eV covalent bond = 3 eV ionisation = 12.5 eV • Only well-established mechanisms is heating • Other mechanisms are being explored and tested in the laboratory Capri, THz, 2002

  28. Conclusion • Most of the research is done in the cm range because of mobile communications • Above 10 GHz, • The skin is the main target • A lot more research is needed for health risk assessment • Exposure systems and biological models are becoming available Capri, THz, 2002

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