Telecommunications & Health Science

Transcription

1 Telecommunications & Health Science Dr. Sheila Johnston Neuroscience Consultant, London WHO EMF PROJECT

2 A. Industry Health Spokesperson Michaela Reeh B. Industry Association FMK C. Independent Science Consultant SAJ 1996 (ICO 96-99) ABC= Sciencefaqs, August 2000 WHO EMF PROJECT

3 eight divisions of information Members Dialogue: BB, Hot issue, Forum, SQ&A Abstracts:Q&A WHO criteria, weight of evidence, Bioeffects: Keydoc, Keyspeech, 6 generic class:human Position Statements, Standards, Key doc, by country, added files Weblinks: govt, operators, science, expert reports WHO EMF Project studies data base: user friendly Worldwide Funding Agencies. WHO EMF PROJECT

4 The RF Bioeffects being Researched RF Bioeffects Cancer-epidemiology Cancer-in vivo in vitro Genotoxicity Nervous system Thermal Anecdotal Interference WHO EMF PROJECT Scientific Reviews Elwood, J. M. 99. Harrison 97 Brusick, D. 98. Hermann D. M NRPB 4: ( 99) Bergquist et al, 97. Medical Devices Agency, 97, UK

5 Sciencefaqs update HOT ISSUES UPDATE 16/Oct/2001 Germany: SSK Limits and precaution-measures -- 24/Sep/2001 Summary, Mobile Phones is there a Health Risk? IBC -- 20/Sep/2001 The Daily Telegraph, England, 19/09/01 Page18 : Science: Is Cancer a call away? -- BULLETIN BOARD UPDATE 19/Oct/2001 The 3G GHz Signal: A Review of Relevant Cognitive Research Source: Sheila Johnston Ph.D. Details next slide 16/Oct/2001 Grenzwerte und Vorsorgemaßnahmen zum Schutz der Bevölkerung vor elektromagnetischen Feldern -- 30/Sep/2001 SAR Initiatives in the USA. IBC Conf: London 09/01 J. Basile VP Ext & Ind. Rel. CTIA 14/Sep/2001 Update on WHO EMF Project Dr Mike Repacholi Helsinki -- WHO EMF PROJECT

6 The 3G GHz Signal: A Review of Relevant Cognitive Research Review of effects on cognition from exposure to MW radiation. The special focus is the 3 GSM signal around 2 GHz Molecular mechanisms of memory storage are highly conserved. Complex memory depends on simplest molecular mechanisms. Spatial memory processes in animals extrapolated to humans. Presently, no reliable scientific evidence that microwave signals of guideline limits, including 2 GHz, signals could interfere with cognition. Research on microwave exposure effects on memory processes draws on molecular memory processes & related signalling & genetic factors from previous invertebrate & vertebrate research: Including cognition, neurotransmitters, receptors, genes & glia & nitric oxide, a possible retrograde messenger for Hebbian associative firing. WHO EMF PROJECT

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19 Consolidation of LT memory is involves 3 processes: 1. gene expression, 2. new protein synthesis and 3. growth or pruning of synaptic connections. WHO EMF PROJECT

20 camp-pka-creb pathway in STM & LTM storage. 4 mutations can cause a defect in the camp cascade: 1.Inducible control over gene expression 2. Block the action of PKA needed to learn even STM 3. Over expression of repressor CREB-2 prevents the camp activated genes, & selectively blocks LTM with out interfering with STM. 4. Over expression of CREB results in LTM even with a training procedure that usually only produces only STM. WHO EMF PROJECT

21 The Mossy Fiber Terminals: Long-Term Potentiation (CA3) Mossy fiber terminals in CA3 release glutamate. CA3, NMDA receptors minor role in synaptic plasticity. LTP depends on Ca 2+ influx into the presynaptic cell (granule cell terminal) after the tetanus. LTP in the mossy fiber pathway is non associative. LTP does not require simultaneous firing in both the postsynaptic CA3 cell & presynaptic dentate cell to adequately depolarise the CA3 postsynaptic cell, a feature called non associativity. WHO EMF PROJECT

22 Schaffer Collateral & Perforant Pathways: Long- Term Potentiation (CA1) LTP in CA1 cells has characteristics distinct from CA3 Glutamate must bind to the postsynaptic NMDA receptor & the membrane potential of the postsynaptic cell must be sufficiently depolarised by cooperative firing of several afferent axons to expel Mg 2+ from the mouth of the channel. The Schaffer NMDA collateral pathway requires simultaneous firing in both postsynaptic CA1 & presynaptic CA3 cells to adequately depolarise the postsynaptic CA1 cell, a feature called associativity. To initiate Ca 2+ influx into the postsynaptic cell a strong presynaptic input sufficient to fire the postsynaptic cell is required. Recent pharmacological and genetic experiments have identified nitric oxide (NO) a gas that diffuses from cell to cell as one of the possible retrograde messengers involved in LTP. WHO EMF PROJECT

23 Conclusion EEG studies are inconclusive & difficult to interpret. Recent human cognitive studies have not followed the WHO criteria for good research. Animal spatial memory researchers (UK, Brooks, Japan & France) found no effect of RF exposure on spatial memory at or below guideline limits. Recent recordings in hippocampal studies suggest no effects of RF on long-term potentiation, and thus explicit memory. Further research of RF on cognition will focus on the molecular mechanism of memory. WHO EMF PROJECT