Talk:Wireless device radiation and health/Archive 1

message: My specific interest at this time is in the dangers of talking on "mobile phones" while operating a motor vehicle. -- More studies and informed discussion on this would be of practical use to the general public/ safety and health. I admit at my current scanning/skimming level I might have missed something. -- [aftercomment]: The "Wikipedia" sites are an inspiration; will continue "hitting". -- [User: Skydogs|TDLturner]19:15, 2006marzo10. (MST)
:Coverage is in a different article: Mobile phones and driving safety.  I added a link to make it easier to find. -- Beland 05:38, 8 December 2006 (UTC)
thread_title: Motor vehicle

message: "according to the scientific consensus, the only effect on the human body is that the temperature of the head may increase by a harmless fraction" - this is not true, there is no such consensus.  convensional wisdom indicates that the only effects of non-ionizing fields would be thermal.  however there is a vast quantity of research, primarily in vitro and on simple animal models, that shows significant effects of nonthermal fields (sometimes very weak ones).  the mechanism of that is not well understood.   that said, there are (as far as i know) no epidemiological studies that show a strong/significant/unambiguous effect from cellphones.  i posted a related comment in Talk:Electromagnetic radiation hazard.  i think that subject merits an article in itself, not just on the hazardous aspects of electromagnetic fields on humans but covering all that is known about the subject so far, and this article can link to that for more info as well as mention here some of the in vitro/animal studies with parameters similar to cellphone exposure.  what do you think?  what should such an article be called?  Biological effects of electromagnetic radiation?  ObsidianOrder 1 July 2005 06:59 (UTC)
There are also many studies showing very little or no effect of non thermal fields.  Plus you have to distinguish between spontaneous variations in a parameter and variations owing to RF.  Mmny of the studies have found fairly insignificant, temporary effects, not shown to cause adverse health effects.  And if you read http://www.mcluk.org/zmirou/zmirou2.htm then you will see that many of the "non thermal fieklds" used have in fact been pulsed, and caused increases in temperature.  —Preceding unsigned comment added by 80.229.27.251 (talk) 12:36, 20 December 2007 (UTC)
thread_title:  scientific consensus? 

message: After consultation with R.Sabbatini, I went through and removed/changed any parts of the article which explicitly state the POV that there are no grounds for health concerns.  I also fixed a few technical inaccuracies and added links.
Todo:
* a decent summary of the in-vitro and animal-model research. this is a huge topic, I guess we just have to sample the high points.
* some more info on epidemiological studies.  is there a meta-review?  can we cite each study we mention?
* some hard data on radiated power from base stations and the typical radiation levels they produce (with sources)
* better explain the importance of "non-ionizing" and "non-thermal"
I'd appreciate it if people can look this over.
ObsidianOrder 05:28, 16 July 2005 (UTC)
thread_title:  the other side of the story 

message: A recent contribution to this article has stated that the human head acts as a parabolic reflector (sic) and generates a moving hot spot inside the brain. I have removed the offending paragraph, because:
# A parabolic lens would be the physical model, not a reflector
# The side of the head around the ear is mostly plane, so the focus, if existent, would be far away at the other side of the head
# The amorphous, electrically conducting and largely irregular structures of the cranium could not act as a lens, but rather as a Faraday cage
# I did a literature review in  and there are no reports that there is such an effect
--R.Sabbatini 15:44, 16 September 2005 (UTC)
replies: text: R.Sabbatini, you're absolutely right about the head not being a "parabolic reflector".  However, near-field effects are very complicated and a "lens" is not a good model either.  In practice when a cellphone next to a head are simulated using a finite elements computation, it turns out that there are usually one or more focal points *inside the head* at which field intensities are >10x greater than what they should be based just on radiated power.  ObsidianOrder 14:21, 29 November 2005 (UTC)
replies: text: Yeah, I agree. but only in part. Some researchers in Brazil have calculated a finite elements model of RF within the head and have "forgotten" to put the effect of bone densities and of heat dispersion by blood circulation in the model... So these focal points could not happen at all! Living heads are active response devices, very finely tuned to maintain temperature, oxygenation, etc. Please send me the reference for a sensible and realistic simulation if you know one. --R.Sabbatini 22:15, 29 November 2005 (UTC)
replies: text: Ok, here you go: a great review with links to more info , and a free online paper from AFRL  (see paragraph 3.2.4 and especially figures  and ).  To summarize: a device with 125mW output power produces average head SAR of a mere 8mW/kg, but at high resolution (1mm grid or finer) there are regions with up to 9.5W/kg SAR (and yes, this is using anatomically accurate models from MRI scans, as do most of the studies in the review article).  That means at peak output conditions of ~1W for a cell phone you'd get SAR up to 76W/kg in some points (but "only" ~20W/kg in the brain). The high-field-strength spots are located primarily at the surface (including the pinnea and skin) and secondarily inside the brain, a locus about 30-40mm directly below the surface adjacent to the antenna.  Yes, you can probably "maintain temperature" even at 76W/kg (that's roughly 1C/minute) but that is completely irrelevant since we are talking entirely about *nonthermal effects*; there is no "active response" to such.  I would also point out that even 8mW/kg is easily sufficient to produce weak nonthermal effects such as affecting melatonin levels or increasing hsp expression (especially with chronic exposure), and 76W/kg is enough to produce some pretty dramatic effects in vitro, including massively modulating Ca2+ efflux, modulating neurotransmitter binding, and literally driving conformational changes in transmembrane proteins.  ObsidianOrder 04:33, 30 November 2005 (UTC)
replies: text: These very high SAR avlues, over what volume (in weight) where they averaged?Mossig 21:42, 25 April 2006 (UTC)
replies: text: Mossig - in this particular report, a volume of 1mm^3.  Yes, these are quite high values, the overall average is much lower (actually 10^5 times lower), but I think you'd agree the existence of such high-field-strength spots could be very biologically significant.  Also please note that the model used, while anatomically accurate to 1mm scale, does not take into consideration the microscopic structure of tissue (capillaries, cells, etc) and those inhomogeneities probably cause much higher local (sub-mm scale) SAR values.  ObsidianOrder 01:42, 25 May 2006 (UTC)

text: Why wouldn't it be a reflector?  Transmitted electromagnetic radiation is partially (or totally, if the angle is low enough) reflected at the boundary between materials of different refractive index, as in the mirror effect at the surface as seen from underwater.  I haven't looked up or tried to think through how refractive index varies with frequency, to see whether the effect would be plausible in the radio frequencies, but if it were visible-wavelength light going through a glass head-shape you would get bright spots where rays converge that were reflected where they would have left the glass.  The same sort of internal reflection is described in explanations of how a rainbow happens.  dsws 02:31, 15 January 2006 (UTC)
replies: text: Dan - several reasons: one, the wavelength is on the same scale as the size of the supposed reflector so you're more likely to see diffraction; two, this is less than one wavelength away from the antenna, hence what happens is near-field propagation which is quite different from far-field reflection/refraction/etc; three, the absorption is strong enough that the signal loses 50% strength within several cm of travel inside tissue, and any reflection off the far side will be quite attenutated; and finally, this has been modelled using finite elements, see one of the diagrams in the article.  The bottom line is you do get "hot spots" below the surface, but the reasons are not optics-like reflection or refraction.  ObsidianOrder 20:25, 15 January 2006 (UTC)
replies: text: Reflection and refraction are large-scale effects due to exactly the same equations that rules near-field behaviour. But you are right in that the SAR distribution often can be very non-obvious.Mossig 21:42, 25 April 2006 (UTC)
thread_title:  Unscientific contributions 

message: Would anyone that's a bit more knowlegable in this area, like to have a look at the related section which covers other Wireless Digital Systems and Health.
I have been uncertain about what possible effects/issues exist in regards to Wireless LAN's.
Thanks
:I have added some data to the article in question, but lots of research on it remains to be done. --R.Sabbatini 11:59, 15 November 2005 (UTC)
thread_title:  Health Issues regarding other Wireless Digital Systems 

message: I'm going to have another go at cleaning up some of this article.  I think there is a little too much editorial POV and "jumping to conclusions".  Encyclopedia articles don't typically have a "conclusions" section ;)  No disrespect intended, and while I think a lot of the material I am about to remove is pretty good, the problem is it is not sourced, and it only presents one side of the story.  I am not opposed to putting it back in if it was properly sourced and if the counter-arguments were fairly presented.  Hope that's ok.  ObsidianOrder 05:06, 30 November 2005 (UTC)
thread_title:  cleanup 

message: The following text is too biased to be left in the article; eg comment about militants, and the sales pitch for MMF Barrylb 17:46, 20 December 2005 (UTC)
replies: text: Yay, you caught one that escaped the last cleanup.  Congratulations ;)  I agree this should go.  Perhaps write something quick that mentions the MMF and that it funds research, without any additional comment?  Also the WHO database stuff (last para) can stay.  ObsidianOrder 03:19, 21 December 2005 (UTC)
thread_title:  Section moved from article: Vested interests in scientific research 

message: I note that in the article, Gerard J Hyland is referenced. I'd like to propose that this be removed, as Hyland has been repeatedly strongly criticised for his work as unreliable, unrepeatable, and unscientific. In particular, Hyland's work was rejected as reliable evidence in the case of Petursson vs Hutchison 3G (2005).  (I appreciate this is from a POV website, mast-victims.org, however the relevant text is a reprint of the judicial verdict):
:74. Dr Hyland lacked balance and impartiality in relation to his evidence in this case. He did not adopt the objective approach which a court expects from an expert witness. Dr Hyland claimed that all the expert bodies (apart from the SSI (Sweden) and Zmirou (France) reviews as to which he had no evidence) lacked honesty, independence and were economical with the truth. This is a bold and startling contention. It would, for example, cast doubt on the integrity of Sir William Stewart (who chaired the IEGMP, and who is now the Chairman of the National Radiological Protection Board) who referred in the foreword to the Stewart 1 report to "the fierce independence" of the group he chaired. I have no hesitation in rejecting Dr Hyland's statement with respect to these eminent and expert bodies. Dr Hyland produced no evidence in support of his contention. His unjustified criticism of national and international groups reflects poorly upon himself and must be viewed in the light of his own partiality in giving evidence in this case. In his reports to this court, Dr Hyland failed to draw attention to the COST 281 Statement. That paper, dated November 2001, is titled Scientific Comment on Individual Statements of Concern About Health Hazards of Weak EMF. It was prepared by an international committee of scientists in response to a submission which Dr Hyland made to the European Parliament. It contains the following: "It is postulated by Dr Hyland that GSM radiation affects the organism. This is supported by the argument GSM 'has rather well defined frequencies' which can interfere with 'a variety of oscillatory electrical biological activities, each characterised by a particular frequency, some of which happen to be close to those used in GSM' in particular 8.34Hz and 2Hz, which 'correspond to those found in the human EEG – especially in the ranges of the alpha and delta brain waves, respectively'. This is non-scientific argument by analogy." The paper sets out those matters, which it says Dr Hyland has ignored, and continues "Therefore postulating that weak GSM signals would affect brain activity just because there is a similarity in the frequency components ignores well-established knowledge.". It goes on to express strong criticism of Dr Hyland's approach eg "not based on generally accepted scientific rules. It is of dubious scientific nature and does not reflect the view of the majority of the accepted scientific experts in the field." This indicates strong condemnation by peers as to his own objectivity and scientific rigour.
DWaterson 21:34, 15 February 2006 (UTC)
thread_title: Source: Gerard Hyland