Talk:Wireless device radiation and health/Archive 1
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Motor vehicle
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)
Old talk
I have added back precautionary measures, because I don't agree that they are NPOV. To make it more palatable, though, I have modified the wording, adapting it to the approach adopted by the World Health Organization precautionary principle for EMF and health.--R.Sabbatini 18:28, 17 Dec 2004 (UTC)
- This paragraph is much better now - the style is much more informative and encyclopedic. ChrisUK 23:22, 17 Dec 2004 (UTC)
To all contributors to this topic: it is very controversial, so please let us keep it neutral and with authoritative links, only. There are thousands upon thousands of articles in the media about the subject, but the majority is written by journalists with second-hand info. I will edit out any contribution that departs from this norm. Thanks for your interest. --R.Sabbatini 22:43, 20 Dec 2004 (UTC)
There's a lot of material in this article that is clearly inappropriate for 'Mobile phone radiation and health'—e.g. the entire 'Indirect health hazards' section... anonymous @ 01:04, 5 June 2005 (EST)
- I don't think so. Since is this by far the highest (and the only one to have solid evidence) risk of using phone cells, it is my opinion that this section should be mantained, regardless of not being caused by radiation per se. --R.Sabbatini 05 June 2005.
scientific consensus?
"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)
the other side of the story
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)
One particular nitpick: sure, inverse-square-with-distance is a pretty rapid dropoff, but it doesn't necessarily mean that the fields are weak, you have to consider that they feed into a high gain antenna first. Take a typical macro-cell base station with 5 (sometimes up to 20) carriers at 15W feeding into a 18dBi gain antenna, that gives a peak ERP (isotropic Effective Radiated Power) of ~700W per carrier (~500W is more common) or ~3500W peak total ERP. In the center of a beam at 100m the peak field is ~3uW/cm^2. (incidentally, these are the kinds of hard numbers on radiated power that the article needs, but from cited sources) That doesn't seem like much if you're looking at the FCC 1.6W/kg standard, but then you have to look at studies such as this one: Magras IN, Xenos TD. RF radiation-induced changes in the prenatal development of mice. Bioelectromagnetics. 1997;18(6):455-61 [1] (showing irreversible infertility in mice at <1uW/cm^2) and this one: von Klitzing. Low-frequency pulsed electromagnetic fields influence EEG of man. Physica Medica. April - June 1995 Vol 11 pp 77-80. (showing EEG changes at <0.1uW/cm^2). ObsidianOrder 06:15, 16 July 2005 (UTC)
This report has a decent summary of the animal and in-vitro experiments related to cell phone safety. It's virtually impossible to give it a concise summary since it covers topics from modulation of calcium efflux to ornithine decarboxylaze to DNA strand breaks (about 30 subheadings, ~40 pages, btw it covers human and epidemiological studies as well). While the people who assembled this report were apparently very conscientious - it is as good a coverage of the literature as I have seen anywhere - I have to disagree with some of their assessments. It seems they do not have a good knowledge of the current theoretical models of interaction of RF fields with tissue (such as IPR, temporal integration or ion channel nonlinearities), which leads them to be skeptical of many observations which actually fit the theory nicely. Anyway, clearly this is too much material for this article, but perhaps a summary of a few paragraphs might work? I'm not sure which parts to pick. A bullet list would demonstrate the broad range of effects but would be otherwise hard to read for most non-specialist readers. Anyway, I really want to include a sense of what's in there without being way too verbose. ObsidianOrder 13:54, 16 July 2005 (UTC)
Unscientific contributions
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 [2] and there are no reports that there is such an effect
--R.Sabbatini 15:44, 16 September 2005 (UTC)
- 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)
- 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)
- Ok, here you go: a great review with links to more info [3], and a free online paper from AFRL [4] (see paragraph 3.2.4 and especially figures [5] and [6]). 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)
- These very high SAR avlues, over what volume (in weight) where they averaged?Mossig 21:42, 25 April 2006 (UTC)
- 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)
- These very high SAR avlues, over what volume (in weight) where they averaged?Mossig 21:42, 25 April 2006 (UTC)
- Ok, here you go: a great review with links to more info [3], and a free online paper from AFRL [4] (see paragraph 3.2.4 and especially figures [5] and [6]). 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)
- 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)
- 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)
- 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)
- 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)
Health Issues regarding other Wireless Digital Systems
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)
cleanup
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)
Section moved from article: Vested interests in scientific research
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)
Some commentators who are militants against the widespread use of mobile telephony have alleged that the mobile phone industry has pressured research institutions to reduce funding for independent investigation of possible health effects, interfered with publicity of research results suggesting health concerns, and attacked the credibility and integrity of such research and researchers. No hard evidence has been provided for this allegations, however.
In fact, it seems to be the opposite: the Mobile Manufacturers Forum (MMF), for instance, applies every year several million dollars for funding independent research on the subject. The money is provided with no strings attached by the biggest manufactureres, such as Motorola, Nokia, Samsung, etc. The MMF is a not-for-profit organization based in Brussels, Belgium. Only research which adheres to the highest methodological standards are funded. Results are required to be published in the best peer-reviewed journals and scientific conferences.
The World Health Organization International EMF Project maintains a public database of research studies which can be consulted on-line [7]. Abstracts of studies are published as well as the complete reference. There are ca. 450 studies in the database related to mobile telephony EMF and health.
- 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)
Source: Gerard Hyland
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). [8] (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)
Health Hazzards of Base Stations
My contribution to this section (see below) was removed by Barrylb. Although there is still no proven causal relationship between brain tumours and Base Towers, the anecdotal evidence is mounting and the situation at RMIT I feel is of sufficient interest (and concern) to justify inclusion. What do others think? --angusj 23:24, 12 May 2006 (UTC)
- Of anecdotal interest, in May 2006, the top two floors of the RMIT University in Melbourne Australia were closed pending further investigation because seven staff members who worked there had contracted brain tumours over a seven year period. On the roof of the RMIT building there is a mobile phone transmission tower. While this does not demonstrate a causal relationship between brain tumours and proximity to mobile phone towers, it is certainly concerning. [9][10]
- It is interesting, but I think it is too soon to include anything in the article. Check out http://www.emfacts.com/weblog/index.php?p=459 for someone else's commentary. -- Barrylb 11:02, 13 May 2006 (UTC)
- Thanks Barry for the interesting link. Yes, seven brain tumours in 2 floors of a building in seven years could be due to other causes. I certainly agree it's too early to point the finger at base towers. Also, this cluster of cases could still be coincidental (though the probability of that seems pretty small). There's a judgement call on what's creating necessary vs unnecessary anxiety in the community, but generally I believe it best to err on the side of too much information and letting others make up their own minds. (As a side note, and having considered the comments made in your link, I'm not easily persuaded that electrical currents to air-conditioning units and lifts are likely to be significant contributors towards causing this cluster of tumours since air-conditioning units and lifts are found in just about every modern building without causing these problems. However, if base towers themselves require sufficient electricity to induce significant EMF exposure then of course that needs to be considered too.) --angusj 13:12, 13 May 2006 (UTC)
- I believe it does belong in the article, its big news at the moment, it's relevant, we just need to be clear that it shouldn't be taken as conclusive evidence. Brendanfox 11:50, 13 May 2006 (UTC)
- Ok, there has been feedback to the previous EMFacts link, saying perhaps the radiation underneath the mobile phone towers could actually be high enough for concern: http://www.emfacts.com/weblog/?p=460
- I also think it is good to "err on the side of too much information" but I suppose my concern was the prominance given to the story - it may be overstating the signficance of the story until we know any more. Perhaps it could be put in a separate current events section. -- Barrylb 22:36, 13 May 2006 (UTC)
OK, I've replaced the paragraph in the original location (pending a better place for it). Also, I've just done a quick calculation on the probability that this cluster of tumours is coincidental - and the probability of that is about 0.1% - ie it's very unlikely. (My calculation was based on an annual incidence of primary brain tumours = 20/100,000 and assumes that the number of people regularly visiting the top 2 floors would be no more than a few thousand.) --angusj 02:48, 14 May 2006 (UTC)
- The stories are saying it was only staff affected. One article says "more than 100 employees" were sent home [11]. So I presume it would be no more than, say, 150 employees. -- Barrylb 04:21, 14 May 2006 (UTC)
- I thought I would do some calculations too... According to statistics at http://www.cancer.gov/cancertopics/factsheet/braintumorstudy the annual incidence of brain tumours for people under 65 is 4.5/100,000, so over 7 years that is about 32/100,000 (I assume Australia is similar to US in brain tumour rates). I plugged in some values at http://home.clara.net/sisa/binomial.htm (expected proportion=0.00032, number observed=7, sample size=150) and it output 0.00000000 probability of it happening... -- Barrylb 06:05, 14 May 2006 (UTC)
- Interesting stuff. I've heard one suggestion that perhaps the peak exposure occured many years ago, and it is only now that the tumours are developing, explaining why the levels can be currently within normal limits. Just on that, does anyone know what the accepted exposure limits are based on? Is there a particularly good study that determined these values? Interested to read how these things are calculated...Brendanfox 07:26, 14 May 2006 (UTC)
- I think the suggestion that "peak exposure occurred many years ago" is absolute rubbish if it's to imply the staff must have been exposed prior to residence in the building. The extremely conservative statistics presented above should pretty much discount any thoughts that this cluster of tumours is coincidental. Also, the 'Telegraph Newspaper' link states that environmental tests were carried out 5 years ago (in 2001) after the first 2 cases were reported and these were reported as 'safe' - so there's nothing to suggest they've improved safety since then. However, it's important to note that none of these workers developed tumours overnight since all tumours take time (usually many months) to develop to clinically detectable sizes. Anyhow, the most likely explanation is that whatever is causing these tumours is undetectable with currently used monitoring devices. --angusj 08:42, 14 May 2006 (UTC)
- Yeah I think the idea was more that there was a peak in exposure at some point (perhaps an incident of some kind) at the actual site, some time ago, but this is clearly very speculative. It's also possible that there's some other factor that the workers have in common. Brendanfox 11:42, 14 May 2006 (UTC)
- Tumours like these probably take something like 10 years to develop. [12] Regarding the exposure limits, they are set based on the level at which thermal affects are known to occur. They take no account of non-thermal affects. I think it is unlikely that the phone towers exceed the exposure limits. If the phone towers are to blame it will be due to non-thermal affects and this is the key battleground for the entire industry. -- Barrylb 12:34, 14 May 2006 (UTC)
- Some slow growing brain tumours may take 10 years to develop but others can develop much more rapidly (and as a retired anaesthetist I've seen quite a few patients with brain tumours). Also, with any kind of EMF radiation both dosage and duration of the exposure are important factors in morbidity. Obviously workers who've been there the longest are at greatest risk. --angusj 14:11, 14 May 2006 (UTC)
- Tumours like these probably take something like 10 years to develop. [12] Regarding the exposure limits, they are set based on the level at which thermal affects are known to occur. They take no account of non-thermal affects. I think it is unlikely that the phone towers exceed the exposure limits. If the phone towers are to blame it will be due to non-thermal affects and this is the key battleground for the entire industry. -- Barrylb 12:34, 14 May 2006 (UTC)
- Yeah I think the idea was more that there was a peak in exposure at some point (perhaps an incident of some kind) at the actual site, some time ago, but this is clearly very speculative. It's also possible that there's some other factor that the workers have in common. Brendanfox 11:42, 14 May 2006 (UTC)
- I think the suggestion that "peak exposure occurred many years ago" is absolute rubbish if it's to imply the staff must have been exposed prior to residence in the building. The extremely conservative statistics presented above should pretty much discount any thoughts that this cluster of tumours is coincidental. Also, the 'Telegraph Newspaper' link states that environmental tests were carried out 5 years ago (in 2001) after the first 2 cases were reported and these were reported as 'safe' - so there's nothing to suggest they've improved safety since then. However, it's important to note that none of these workers developed tumours overnight since all tumours take time (usually many months) to develop to clinically detectable sizes. Anyhow, the most likely explanation is that whatever is causing these tumours is undetectable with currently used monitoring devices. --angusj 08:42, 14 May 2006 (UTC)
- Interesting stuff. I've heard one suggestion that perhaps the peak exposure occured many years ago, and it is only now that the tumours are developing, explaining why the levels can be currently within normal limits. Just on that, does anyone know what the accepted exposure limits are based on? Is there a particularly good study that determined these values? Interested to read how these things are calculated...Brendanfox 07:26, 14 May 2006 (UTC)
- Brendanfox - current limits are based solely on thermal exposure models. If it won't (literally) fry you, it's safe. This leads to limits in the 10's of W per kg levels or single W per kg for continuous exposure, just to be safe. This is probably a very useless measurement, considering that people have observed nonthermal effects at microwatts per kg levels. The problem is that such effects are not easy to reproduce... some evidence indicates that the results may be affected by ambient RF noise, or the strength and relative orientation of constant magnetic fields (the Earth's magnetic field, for example). That means that you could live next to a powerline and get cancer from it, but your neighbor (for whom the powerline and Earth magnetic fields intersect at a different angle) is perfectly safe. It is not a simple matter, and gross epidemiological studies can completely miss that. ObsidianOrder 02:26, 25 May 2006 (UTC)
The final report RMIT report is available here. Their media release says "there is no brain cancer cluster on the top floors". There is an interesting independent response here -- Barrylb 21:26, 13 August 2006 (UTC)
- Thanks Barry for the interesting link to the independent response. (The obvious solution now is to move RMIT administration into the 2 floors in question.) --angusj 22:09, 13 August 2006 (UTC)
Moved from article - Conclusions
This new section sounds like original research and POV to me. -- Barrylb 16:12, 21 May 2006 (UTC)
Mobile phones and its corresponding base stations seem to be remarkably safe devices, as far as the majority of well accepted and reproducible experimental and observational studies could determine. They are in use for more than 30 years, so long range effects have also been taken into account. They are used by more than a billion users worldwide, and vast numbers of people are constantly exposed to low-level, non-ionizing radiation coming out of base stations, so lack of a strong statistical base is not an issue. The spectrum of radio waves used for communication for more than a century, at intensities orders of magnitude larger than microwave radiation used in mobile telephony, an exposing even larger numbers of people, has not been implicated either.
A number of common sense and science-based facts would sum up to the conclusion that significant ill effects are improbable:
- Even with a very low risk ratio, an increase in the number of several diseases which have been attributed to low-level microwave radiation would be easily detected, and this has not been the case;
- The penetration power of microwaves into the human body is very low. Most of the radiation is converted to heat within a few millimeters of external anatomic structures and clothing. Those who are not afraid of being exposed to visible light in reasonable amounts, should not fear microwave radiation, which has many properties of weak visible light toward the infrared range, i.e., they have comparatively lower power density than light, lower frequencies, are non-ionizing, non-cumulative, and with too large a wavelenght to promote interaction with subcellular structures
- The levels of radiation emitted by base stations is too low to be biologically significant, and represent an increase of a few tenths of microwatts per cm2 over the already-existent microwave background radiation of a typical modern city.
- Emission power absorbed by the human body are higher for handsets, but they are typically used only a few minutes per day close to the head;
- Exposure limits defined by international standards, such as ICNIRP, are typically 50 or more times lower than the biological safety limit. If they are respected, biological effects are
extremely improbable.
- Are you really antagonizing the additions to this article, which was started by me in the first place? What is your agenda?? Of course conclusions are warranted. Of course they are not a POV unless you have a POV. They are NPOV, based on published evidence. But I have renamed it to Summary and will reinsert it back as many times as I wish. If you want to submit this to a votation, please do. --R.Sabbatini 16:17, 21 May 2006 (UTC)
- Sorry I upset you. As you probably know, Wikipedia has a No original research policy which they summarize as:
![]() | This page in a nutshell: Articles may not contain any unpublished theories, data, statements, concepts, arguments, or ideas; or any new analysis or synthesis of published data, statements, concepts, arguments, or ideas that serves to advance a position. |
- This section appears to violate that, whether you call it Conclusions or Summary or whatever. -- Barrylb 16:35, 21 May 2006 (UTC)
I agree with Barrylb. The evidence regarding the safety of mobile base stations in particular is still very scant for reasons touched on in the main article. Also, I'm still of the view that the recent cluster of brain tumours at RMIT is of sufficient interest and concern to warrant a comment in the main article. It appears that the paragraph mentioning the RMIT issue has been removed. --angusj 03:16, 22 May 2006 (UTC)
- I agree too. This section presents one POV very nicely, but that's not we're here to do (at least not without presenting the other side). -- Avenue 04:18, 22 May 2006 (UTC)
"remarkably safe devices" - RSabbatini, I gotta give you this, you're certainly not trying to hide your POV. Now, I wouldn't say that they are remarkably dangerous, but I am not so sure they are safe either... and there is a huge controversy in the published literature about that. For an encyclopedia to state as a fact that they are safe when there is such a controversy is an example of extreme (and unacceptable) POV. Yes, I also agree with Barrylb, the "Conclusions" section was in violation of NOR. I am going to attempt to clean up the rest of the article (again), while preserving any sourced material, please bear with me. ObsidianOrder 01:01, 24 May 2006 (UTC)
cleanup again
Cut a number of bogus statements which fall under the general category of opinions presented as undisputable facts, examples:
- "Currently the only universally accepted biological effect of microwaves is heating" - which is why there are 3000+ papers on non-thermal effects
- "they are unable to interact with microscopic cell structures" - only if you don't understand the interaction mechanism
- "[The WHO] have concluded that there is no convincing evidence for harmful effects" - actually, they've concluded quite the opposite, as judged by their recommendation of the precautionary principle applied to this
- "relative risk is comparatively small" - opinion
- "One should be aware that that documented effects..." and "... should be considered with great caution" - really not our place to say that. Find an expert who says that and quote him if you want.
- "mere 30 metres away ... would be extremely unlikely to occur" - opinion, POV writing
- "media exposure frenzy created around conflicting and often badly conducted scientific studies" - opinion, POV writing
Please note that I left all of the sourced information, including stuff in the biblio and quotes from various reports, no matter how lame. I will be expanding the section that talks about the Stewart report shortly. ObsidianOrder 01:18, 24 May 2006 (UTC)
"only if you don't understand the interaction mechanism" Oh dear it seems like Obsidian Order is referencing the discredited work of Gerald Hyland, whose theory on the mechanism of non thermal fields on health has never been proven and which has been condemned by his peers. —Preceding unsigned comment added by 80.229.27.251 (talk) 12:53, 20 December 2007 (UTC)
- More than 3000 scientific articles that documents non-thermal effects? I have seen this statement before, but never seen any list of these alleged papers. Please give a reference to such a list, or at least the first 1000 papers. Mossig 17:21, 24 May 2006 (UTC)
- Mossig - I will gladly get you started. Here are the first 500: [13]. Want more? You'll have to do some digging ;) Search MEDLINE [14] for anything by the following authors: "Adey WR", "Blackman CF", "Becker RO", "Frey AH", "Blackwell RP" (many more, but these come to mind first, their work is almost exclusively in this area...) and also for "magnetic fields" or "electromagnetic" or "microwave" in combination with one of the following terms: calcium, embryo, melatonin, ornithine, "bone healing", opioid, cholinergic, analgesia, hyperalgesia, "power frequency", "power line", VDT, ... That should easily get you over the 1000 mark, probably close to 2000. Enjoy. ObsidianOrder 23:03, 24 May 2006 (UTC)
- P.S. Mossig - alternatelty do this exact search on MEDLINE: ("magnetic fields" OR electromagnetic OR microwave) AND (opioid OR cholinergic OR embryo OR melatonin OR calcium OR ornithine OR "bone healing" OR expression OR analgesia OR modulation) -> 2661 results, from a random sample I'd say about 75% are directly relevant. A random pick from the middle, #1318 "Flipo D et al, Increased apoptosis, changes in intracellular Ca2+, and functional alterations in lymphocytes and macrophages after in vitro exposure to static magnetic field. J Toxicol Environ Health A. 1998 May 8;54(1):63-76." Do I even need to explain why a static field is completely non-thermal? Or why this is a flat-out impossible result according to the conventional (forces exerted on molecular dipoles) theory of interaction of biological systems with magnetic fields? ObsidianOrder 23:18, 24 May 2006 (UTC)
- One more for you: WHO EMF project bibliography [15] - just hit search -> "There are 2679 studies that match your criteria" ObsidianOrder 00:25, 25 May 2006 (UTC)
- The paper you use as an example is regarding static fields, which by definition is not microwaves. There are a lot of research also being done, and non-thermal effects shown, for low frequency fields. Regarding your list: The first paper is not a scientific publication, it is a discussion. The seconds discusses thermal effects. A couple further down discusses influences on driving when talking in a mobile phone, which may be due to the microwaves, or due to the cognitive task of having a conversation. etc. (The list even includes papers from the EU regarding the precautionary principle!) Please give me a list of 3000+ scientific articles that show non-thermal effects of microwaves. (And btw, Yes, I know how to do scientific searches. And I have done them. And I am very sceptical that there are 3000+ papers in existance which shows non-thermal effects of microwaves. As you assert that they exist, it is up to you to show that they do.) Mossig 12:01, 25 May 2006 (UTC)
- Regarding the WHO-database: the search result of 2679 includes 710 review articles, which gives 1969 articles of original research. If we narrow it down to microwaves related articles, we get 1837 relevevant articles. The list includes high-power, ie. thermal studies. And it includes negative results, ie. no effects were shown from microwave radiation. The database also includes non-peer reviewed articles...Mossig 12:31, 25 May 2006 (UTC)
- "very sceptical that there are 3000+ papers in existance which shows non-thermal effects of microwaves" - not exactly what I claimed. I would estimate that the total scientific literature about non-thermal effects of EMF (any frequency) consitis of ~3000 papers. Please bear in mind that all the conveniently accessible indexes do not include most of the Russian and Chinese literature on the subject, which is very extensive. So 2000 in MEDLINE is something like 3000 total. Of these 20 or 30% report negative results, and some smaller percentage are reviews or theoretical studies. Probably less than 50% of the remainder is specifically about microwaves or RF. I would estimate 400-600 experimental studies reporting positive non-thermal effects of microwaves specifically, and 100-150 studies reporting no effect. I hope that clarifies things. ObsidianOrder 16:08, 25 May 2006 (UTC)
- As a regular reader of the scientific press, my estimates of the percentage of negative resutls articles is considerable higher. I am still waiting for the specific list so that it can be discussed.Mossig 16:24, 25 May 2006 (UTC)
- Hang on, I will get you a list. From a small random sample of the IEGMP biblio, I get 12 positive, 1 negative, 7 not about microwaves or not an experimental study. My percentage of negatives may actually be high. ObsidianOrder 16:42, 25 May 2006 (UTC)
- Mossig - got your list, see the msg at the bottom. ObsidianOrder 21:56, 25 May 2006 (UTC)
- "regarding static fields" - the question was papers about non-thermal effects of any type, I believe. I did not say microwave-only and neither did you. If there are non-thermal effects, it is likely they would occur in a wide range of frequencies, depending on the interaction mechanism(s), as indeed has been shown to be the case. For one thing, any non-linear medium (tissue) would demodulate RF or microwave fields down to ELF. Also, the reported ELF effects occur at SAR numbers in the milli-, micro- or sometimes nano-watt per kg level, which demonstrates that "thermal" SAR limits are based on a faulty premise. So ELF non-thermal effects are quite relevant to cell phones, although indirectly.
- The question was about microwaves specifically. You stated in the beginning of this sections: ""Currently the only universally accepted biological effect of microwaves is heating" - which is why there are 3000+ papers on non-thermal effects". If that was not what you inteded to say then your phrasing is bordering on the dishonest.Mossig 16:24, 25 May 2006 (UTC)
- I see what you mean. I guess I don't really tend to think of such a strong distinction between effects at different frequencies - except for ELF (where a 0.01Hz sometimes makes a big difference), the observed effects are usually remarkably non-frequency-sensitive (or I should say, not carrier-frequency-sensitive, they are quite sensitive to modulation). Based on my reading of the literature the existence of nonthermal effects at any frequency strongly implies the existence of some effects at other frequencies as well. The main point is the existence of (one or more) non-thermal primary interaction mechanisms. ObsidianOrder 16:42, 25 May 2006 (UTC)
- "The first paper is not..." - you're nitpicking. The IEGMP biblio is full of examples of what you want - how about, for example: "Adey W R, Bawin S M and Lawrence A F (1982). Effects of weak amplitude-modulated microwave fields on calcium efflux from awake cat cerebral cortex. Bioelectromagnetics, 3, 295.". There are several hundred of those in there. If you really want, go through and count the number of experimental studies about microwaves specifically, I would actually be quite interested in the percentage.
- The title does not show if they had a positive or negative result, and the paper is so old so that it is not available in electronic format. Thus I can not check it at the moment. An Why should I do the work of proving your conjectures? Mossig 16:24, 25 May 2006 (UTC)
- "it includes negative results" - yes, indeed, I didn't say papers which show non-thermal effects, I said papers on non-thermal effects. I would say somewhere between 20 and 30% report negative results. I was also including theoretical studies and review articles.
- "narrow it down to microwaves related articles, we get 1837 relevevant articles" - isn't that quite a lot already? The WHO database while quite good is not exhaustive, so the real total is higher. Also see above re: non-English/Western literature. ObsidianOrder 16:08, 25 May 2006 (UTC)
- You are using the total number of articles in the field of research to argue for your poit of view, regardless of what they showed? Intriguing tactic, but it is not science. You can only use the articles that support your view, and I am still waiting for that list.Mossig 16:24, 25 May 2006 (UTC)
- Regarding "Currently the only universally accepted biological effect of microwaves is heating" - this statement is intended to mean that everyone accepts the heating effects. It is not intended to dismiss non-heating effects. Just that not everyone accepts them. -- Barrylb 19:00, 24 May 2006 (UTC)
- Technically correct, I suppose, but it was hardly an example of neutral writing. ObsidianOrder 00:25, 25 May 2006 (UTC)
- You should have seen the original sentence by another author: "The only known and clearly documented biological effect of microwaves is heating". I edited that into the one you quoted. -- Barrylb 07:03, 25 May 2006 (UTC)
- Heh. Sorry if I sounded like I was picking on you, that was not my intention. ObsidianOrder 16:13, 25 May 2006 (UTC)
- You should have seen the original sentence by another author: "The only known and clearly documented biological effect of microwaves is heating". I edited that into the one you quoted. -- Barrylb 07:03, 25 May 2006 (UTC)
- Technically correct, I suppose, but it was hardly an example of neutral writing. ObsidianOrder 00:25, 25 May 2006 (UTC)
OK, here is an exhaustive search of all MEDLINE records specifically about nonthermal effects of microwave or RF radiation from Jan 2005 to the present, organized in three categories: positive (non-thermal effect definitely observed, 38 articles), negative (no non-thermal effect observed or dubious, 29 articles) and other (not an experimental study - reviews, letters to the editor, and theoretical studies, 14 articles). These are in bibtex format. Considering that this covers just a year and a half, and the subject has been studied for ~30 years, my original numbers are about right (400-600 positives), although possibly the number of negatives I cited was low (it's probably around 200-300). I can do 10 years if you want, this is kind of fun ;)
I would also mention that there was a lot of studies on (for example) in-vitro Ca++ efflux in the 80's which were mostly positive, whereas recent work is often on whole-animal models studying cell-phone-like exposure, which are often negative. It is also notable that virtually none of these studies control the total EM envitonment, including static magnetic fields and broad-spectrum noise, and those can and do critically influence the results.
Now, what does this all mean? Is there a non-thermal effect (or category of effects)? Yes, obviosuly, there is. Is it reproducible? Also obviously not very well reproducible - although some of the factors affecting that are by now well known, most studies still fail to take them into account. Is it a strong effect? Sometimes it is, usually not very. Is it physiologically or medically significant? Again, maybe, and in some circumstances - usually in a health adult organism it is similar to a relatively weak generalized stressor. Can we conclude that modulated microwaves are "generally safe", and can safety be established with SARs? Hell no! But the dangers would usually only manifest in combination with other factors (physical or chemical). SARs are irrelevant since EMF effects rarely or never have a traditional dose-response relationship, moreover effects are observed at ridiculously low power densities. Just my two cents. ObsidianOrder 21:56, 25 May 2006 (UTC)
- Very interesting. I will look at the list later. But I have to ask you how you define "non-thermal"? The usual "definition" is effects shown below todays SAR-limits, but the first article in your positive list seems to be working at levels of 2.4W/kg, which is above? Further articles seems to be testing at the limits, and one even has "high power microwaves" in the title. Mossig 22:43, 25 May 2006 (UTC)
- If effects occur at levels only marginally above the current limits then there is still cause for concern that the limits are not adequate. -- Barrylb 09:33, 26 May 2006 (UTC)
- Mossig - yes, some of these are testing at the limits, they are included here because there are definite effects reported which cannot be attributed to temperature. As procedures with a "thermal intent" such as PRF treatment of nerves and RF ablation have become more common in medical practice, people started observing results which are frankly quite bizarre, such as growth of new nerves in the area adjacent to RF ablation. So some of the studies address that, and yes, the power levels are a bit high for those. Needless to say, other studies have vastly lower power levels.
- Barry - yes, indeed, particularly since according to the ARFL study cited in the article a 1W cell-phone will cause localized areas of up to 20W/kg in the brain and 76W/kg in surface tissues. ObsidianOrder 15:13, 26 May 2006 (UTC)
- Are you here referring to the SAR values taken over one voxel, ie. over a volume of 1mg? These are absolutly not comparable to the limits for volumes of 10g and 1g resp. It is not possible to compare SAR values taken over different averaging volumes. To do so is very very wrong. Mossig 22:41, 26 May 2006 (UTC)
- I admit I fail to see the logic of this. If a SAR of X under uniform exposure is sufficient to produce effects, for example in vitro, surely under non-uniform exposure you would expect any areas with a SAR above X to exhibit effects - no matter how small or large that area is? In fact the only meaningful scale to calculate SAR over is a scale such that the field is essentially uniform over it, which in the case of cell phones would be one to several mm, no larger. ObsidianOrder 18:51, 27 May 2006 (UTC)
- The problem is that there is no way to have an uniform exposure. All studies I have seen give their SAR values as average exposure over the whole cell culture or animal. Thus it is not possible to compare these values with spatial peak voxel values. This as we do not know the spatial peak values in the experiments, and they are not possible to claculate without very precise knowledge about the experimental setup.Mossig 22:02, 27 May 2006 (UTC)
- Well-done in-vitro studies typically take steps to ensure uniformity, or measure the degree of non-uniformity. Cellular or tissue-level studies commonly use samples of a few mm in their smallest dimension, so exposure is essentially uniform. Your point is partially correct for MW studies of whole organisms, given the rapid attenuation of MW in tissue, but even then, the typical setup is a TEM waveguide which is far more uniform than the near-field of an antenna. For most RF (not MW) studies, exposure is fairly uniform over the whole organism.ObsidianOrder 23:51, 27 May 2006 (UTC)
- Please show me a reference to an exposure system that is uniform, as verified by FDTD-simulations. I am very interested in finding such a system! A TEM-cell gives nothing even close to uniform absorption in the body of the animal or even in a Petri dish: "Investigation of SAR uniformity in TEM cell exposed culture media", Andrews, E.F. et al.; Journal: Antenna Measurements and SAR, 2004. AMS 2004.Mossig 10:13, 28 May 2006 (UTC)
- Well-done in-vitro studies typically take steps to ensure uniformity, or measure the degree of non-uniformity. Cellular or tissue-level studies commonly use samples of a few mm in their smallest dimension, so exposure is essentially uniform. Your point is partially correct for MW studies of whole organisms, given the rapid attenuation of MW in tissue, but even then, the typical setup is a TEM waveguide which is far more uniform than the near-field of an antenna. For most RF (not MW) studies, exposure is fairly uniform over the whole organism.ObsidianOrder 23:51, 27 May 2006 (UTC)
- The problem is that there is no way to have an uniform exposure. All studies I have seen give their SAR values as average exposure over the whole cell culture or animal. Thus it is not possible to compare these values with spatial peak voxel values. This as we do not know the spatial peak values in the experiments, and they are not possible to claculate without very precise knowledge about the experimental setup.Mossig 22:02, 27 May 2006 (UTC)
- I admit I fail to see the logic of this. If a SAR of X under uniform exposure is sufficient to produce effects, for example in vitro, surely under non-uniform exposure you would expect any areas with a SAR above X to exhibit effects - no matter how small or large that area is? In fact the only meaningful scale to calculate SAR over is a scale such that the field is essentially uniform over it, which in the case of cell phones would be one to several mm, no larger. ObsidianOrder 18:51, 27 May 2006 (UTC)
- Are you here referring to the SAR values taken over one voxel, ie. over a volume of 1mg? These are absolutly not comparable to the limits for volumes of 10g and 1g resp. It is not possible to compare SAR values taken over different averaging volumes. To do so is very very wrong. Mossig 22:41, 26 May 2006 (UTC)
- To answer the question of what is non-thermal: any effect which cannot be reproduced by equivalent heating is non-thermal. If there is no measurable heating, the effect is non-thermal by definition. If for example there is substantial heating, but the effect is only observed with modulated RF and not with CW RF of equivalent power (or perhaps the effect is frequency-dependent, or only occurs in a narrow power window, etc) then that is also a non-thermal effect despite the fact that there is heating. ObsidianOrder 00:01, 28 May 2006 (UTC)
- I prefer the following definition, taken from , "Biological Effects of Electromagnetic Fields-Mechanisms for the Effects of Pulsed Microwave Radiation on Protein Conformation", LAURENCE, J.A. et. al, J. Theor. Biol.(2000) 206. "An athermal exposure to microwaves is one which does not cause the temperature of a specied volume of the subject averaged over a specied time period to exceed the normal value." The paper also includes some interesting ideas on the background to some of the athermal effects noticed.Mossig 10:57, 28 May 2006 (UTC)
- Mossig - athermal is not the same as nonthermal ;) athermal means (without) heat (heat is absent), and nonthermal means (other than) heat (heat, even if present, is not the causative agent). (cf anaerobic and nonaerobic). See Becker and Marino, "Electromagnetism and Life" [16] for an interesting perspective. P.S. Yes, I have seen FDTD (or FEM) simulations of experimental setups, as well as direct measurements, stay tuned - I don't have time to look for that right now but I'll have it in a day or two. ObsidianOrder 01:57, 1 June 2006 (UTC)
- Still waiting for the references... And the text, even though it is old, was interesting. I especially liked the passage: "From an evolutionary standpoint, nature would favor those organisms that developed a capacity to accept information about the earth, atmosphere, and the cosmos in the form of electromagnetic signals and to adjust their internal processes and behavior accordingly." A sad fact for the authors is that this is as much nonproven today as it was then.Mossig 00:04, 18 June 2006 (UTC)
- Mossig - athermal is not the same as nonthermal ;) athermal means (without) heat (heat is absent), and nonthermal means (other than) heat (heat, even if present, is not the causative agent). (cf anaerobic and nonaerobic). See Becker and Marino, "Electromagnetism and Life" [16] for an interesting perspective. P.S. Yes, I have seen FDTD (or FEM) simulations of experimental setups, as well as direct measurements, stay tuned - I don't have time to look for that right now but I'll have it in a day or two. ObsidianOrder 01:57, 1 June 2006 (UTC)
- I prefer the following definition, taken from , "Biological Effects of Electromagnetic Fields-Mechanisms for the Effects of Pulsed Microwave Radiation on Protein Conformation", LAURENCE, J.A. et. al, J. Theor. Biol.(2000) 206. "An athermal exposure to microwaves is one which does not cause the temperature of a specied volume of the subject averaged over a specied time period to exceed the normal value." The paper also includes some interesting ideas on the background to some of the athermal effects noticed.Mossig 10:57, 28 May 2006 (UTC)
- To answer the question of what is non-thermal: any effect which cannot be reproduced by equivalent heating is non-thermal. If there is no measurable heating, the effect is non-thermal by definition. If for example there is substantial heating, but the effect is only observed with modulated RF and not with CW RF of equivalent power (or perhaps the effect is frequency-dependent, or only occurs in a narrow power window, etc) then that is also a non-thermal effect despite the fact that there is heating. ObsidianOrder 00:01, 28 May 2006 (UTC)
- Hi Mossig, sorry for the delay in responding... yes, here are some references: [17] [18] [19] [20] [21]. As you see the maximum variation - both as calculated and as measured - using standard containers (Petri dishes or rectangular flasks) is on the order of 3dB. Non-standard container/exposure systems like strip-lines can bring that down to maybe 0.5-1.0dB, but are not used in most studies. Compare that with the AFRL model of a head which has a variation on the order of 36dB, and the variation in whole-organism studies using small lab animals which are on the same order of magnitude, 20-30dB. The point is that if in-vitro studies show an effect at a certain power level, then a whole organism in which any part is at that level can reasonably be expected to have a similar effect in that part, and so looking at the peak voxels in a whole-organism FDTD simulation is correct. ObsidianOrder 02:57, 14 November 2006 (UTC)
- I do not agree. The first reference gives a variation of +8/-72 dB of max/min SAR in the testtube relative the mean (figure 4). Other tests in the same article gives numbers of +6/-78 dB (figure 8), +8/-36 dB (figure 11) etc. The second reference gives similar numbers: +7/-17 dB (figure6). The third article does not give enough statistical data to evaluate the spread of the exposure. The fourth does only give data on the bottom of the petri dish. And it goes on to state that the maximum deviation can be up to 1W/kg at the edge, and thus they dont include the edge in their calculations! The fifth article does not state maximum and minimum calculated SAR-values. In conclusion I can not see that these articles backs the statement that the variation in the peak voxels are on the order of +3dB. Mossig 15:26, 1 January 2007 (UTC)
- Welcome back ;) Please look carefully at the fourth article. The liquid layer they are working with is only 2mm thick (as I had mentioned, well-done studies use thin films). Thus 1mm from the bottom is right in the middle vertically, and vertical variation is very small. In terms of horizontal distribution, Fig.5 shows (on the right) -2 to -8dB approximately, where the whole cell average is just under -2 and the area close to -8 is very small (most of the volume being within +/-1dB of -2). This meets my +/- 3dB specification exactly. Other good studies are roughly on par with this. I think in general "cold spots" or localised areas with much lower field strength are both inevitable and far less important than "hot spots"... if an exposure system produces +/-1dB over 80% of the volume and the other 20% is lower, in parts much lower (this describes most competent real-life setups), then the behavior in that in vitro system at a given average SAR can reasonably be extrapolated to in vivo effects in voxels with the same peak SAR. Unless you think that the effect occurs only in the cold spots? P.S. I think you're going to prompt me to write a paper or two on this... if highly uniform exposure is so important, I know how to produce it ;) ObsidianOrder 09:34, 30 January 2007 (UTC)
- So we are down to one article. Which I have numerous issues with, but lets keep to the SAR-variation. Fig. 5 to the right shows a variation between 1.7W/kg and 0.1W/kg, or 12dB. A lot more than the 6dB, or +/-3dB. My main concern is not about the cold spots, but about the (really) hot spots, typically at the edges: as all the in vitro and in vivo tests shows small effects, these may be due to only things happening in the hot spots, which makes the common use of the mean SAR fallacious. But that part is Original Research, and may very well be published one day... Mossig 10:48, 30 January 2007 (UTC)
Sensitivity to Digital Microwave Wireless Signals
It would be interesting to conduct a survey on how many people are experiencing interference to their nervous systems or eye problems from using microwave wireless technology such as cellphones or wireless LAN's. But doing a respectable survey could prove troublesome because those who have no problems tend to deride those who do as if they are hypochondriacs and dismiss their reports as nonsense.
I find when I use a mobile phone or PDA with WiFi, I start to experience problems with my nerves and also eyes. It seems like the digital microwave signals are somehow interfering with my nervous system. Here are some observations I have experienced:
- Sensations of false vibrations, particularly lower legs and arms
- A tight (or false pressure) feeling on scalp when using a cellphone
- Twitches and spasms
- Itchy and swollen eyes and small flashes in peripheral night vision when moving eyes
- Slight dizziness and disorientation and often a headache that develops
These symptoms are most pronounced when holding and using the device (cellphone or WiFi PDA) and develop very quickly upon commencement of use. They tend to slowly fade away over 12 to 24 hours after cessation of usage, although they can sometimes persist for a longer duration. When sitting near a device (within a couple of feet), the symptoms take much longer to develop (after about 15 minutes of web browsing on a WiFi PDA at a distance of a bit over a foot - although much contact is made with the stylus in selecting links etc...) and, particularly the nerve problems, are much less noticable. -PaulSyd 17-09-2006.
- Unfortunately, attempting to conduct any sort of survey would be very much original research, and therefore unsuitable for inclusion in WP. DWaterson 11:18, 17 September 2006 (UTC)
- Unless it's a government or corporation who's funding it.
- Nevertheless there is a long way from proposed research to inclusion in an encyclopedia. Although interesting it's true that this would not be suitable Wikipedia material. Winston.PL 21:57, 15 September 2007 (UTC)
- Unless it's a government or corporation who's funding it.