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Study Links Cell Phones and Eye Cancer
Sara Chan writes "There have been lots of claims that cell phones might cause cancer. The Sunday Times of London reports that there now seems to be real evidence to show these claims are true, at least for cancer of the eye. A study found a strong statistical link and a feasible mechanism is known: microwave radiation is absorbed by
certain cells (melanocytes) in the uveal layer of the eye (which affects their growing/dividing). The study
appeared in the journal Epidemiology
and the abstract is available here."
Now we'll have to deal with blind people on cell phones in traffic.
Disclaimer: I'm a physics student. This means I know a bit about the subject, but certainly not everything.
The mechanism by which the radiation might cause cancer is uncertain but it is known that the watery contents of the eye assists the absorption of radiation.
The watery portion of the eye would only experience very mild thermal effects (heating). Microwaves aren't ionizing radiation.
Other research showed that cells called melanocytes found in the uveal layer started growing and dividing more rapidly when exposed to microwave radiation.
Since uveal melanoma starts within such cells, there is a ready-made mechanism by which mobile phone radiation might help to initiate cancer, especially in people with a genetic predisposition to the condition.
This is a poor explanation. If microwaves cause unusual growth rates among the melanocytes, then microwave radiation could act as a promoter, not an initiator, of cancer. Ultraviolet light is both a promoter and an initiator, because it is high-enough energy to ionize DNA molecules and cause mutations. Microwaves are non-ionizing, so there is no known mechanism by which they could act as an initiator.
As for increasing growth rate of melanocytes, this is hardly surprising. Melanocytes reproduce and produce pigment in response to electromagnetic radiation (this is how you tan). It would have to be shown that melanocytes reproduce at an unusually high rate when exposed to microwaves (of the levels emitted by cell phones), as compared with the reproduction rate from exposure to sunlight. In short, until someone shows that melanocytes react more strongly to cell-phone level radiation than to sunlight, this is a straw man.
When the results were analysed they found the cancer victims had a much higher rate of mobile phone use,
They found a correlation. That's not the same as cause-and-effect. One strong factor that many people overlook is socio-economic effects. For instance, perhaps affluent Brits are more likely to own cell phones and more likely to go on vacations to places to sunny places. People who are normally exposed to low levels of ultraviolet light (i.e. Brits) who suddenly find themselves in sunny climates have very little skin pigment, and are much more prone to get cancer-causing sunburns (or perhaps eye damage) than those accustomed to those levels of sun.
though Stang cautions that his study needs confirmation
Good for him. It sounds like he's a responsible scientist who's found a correlation worthy of further increase. He also has at least the beginnings of a mechanism to explain the correlation. Unfortunately, the Sunday Times has done the usual media thing, and overreacted. One study does not a fact make.
Sadly, the lawyers will probably jump all over this. It's not like science, truth, or facts ever had any place in the courts...
According to the abstract the conclusions are based on intreviews with volunteers (self-selection being one confounding factor). The only source of informatiuon is the interview script, making it likely that many other corrolations were missed in questions unasked.
No mention was made about conmtrolling for even such obvious effects as family medical history
The "control" is an interpretation control but not a test grou pcontrol. Given that herte is no control on the writing of the questions, control on the interpetation of the results is of minimal value.
In short, this looks like very very very BAD science.
It's true of cigarettes...
# debian/rules
Second-hand cell-phone radiation is not a threat, due to the inverse-square law. The cell phone is 5 cm (2") from the user's head, whereas it's probably at least a metre (3'3") from your head. That means you recieve about one quarter of one percent of the radiation the user does. Hardly significant.