Given how much attention this issue has been receiving as of late, it seems worthwhile to draw attention to this story:
A major review of previously published research by a committee of experts from Britain, the United States and Sweden concluded there was no convincing evidence of any cancer connection.
It also found a lack of established biological mechanisms by which radio signals from mobile phones might trigger tumours.
"Although there remains some uncertainty, the trend in the accumulating evidence is increasingly against the hypothesis that mobile phone use can cause brain tumours in adults," the experts wrote in the journal Environmental Health Perspectives
The latest paper comes just two months after the World Health Organisation's (WHO) International Agency for Research on Cancer (IARC) decided cellphone use should be classified as "possibly carcinogenic to humans."
Anthony Swerdlow of Britain's Institute of Cancer Research, who led the new review, told Reuters the two positions were not necessarily contradictory, since the IARC needed to put mobile phones into a pre-defined risk category.
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Significantly, other studies from several countries have shown no indication of increases in brain tumours up to 20 years after the introduction of mobile phones and 10 years after their use became widespread, they added.
Proving an absence of association is always far harder in science than finding one, and Swerdlow said it should become much clearer over the next few years whether or not there was any plausible link.
What of that apparent disconnect between this latest research and the recent decision by the WHO's IARC? Some further explanation here of how this all squares:
The ICNIRP evaluation also considered the data on brain cancer incidence in several countries with reliable records, including Nordic Countries, Switzerland and the US; in all cases there has been no indication of an increase in brain tumour incidence (as I discussed previously, the trend is the same in Canada).
Overall ICNIRP concluded that the combined evidence suggests that there is no significant increase in adult brain tumours within 10 to 15 years of cell phone use, but noted that there are no data on the risk of childhood tumours.
These two evaluations do not really contradict each other as much as it might seem. Neither give a clear black and white conclusion – both show that the available studies have significant flaws and biases that make it difficult to draw solid conclusions. The two evaluations were done using a different approach; IARC looked at the evidence within a specific framework and set of rules for comparison with other evaluations, while ICNIRP looked at the overall weight of evidence and tried to make general conclusions.
Both evaluations acknowledge some major shortcomings in the data. In particular, cell phone use has only really been widespread for about 10 years, and some cancers may take longer than that to develop. There also aren’t any good data for risks to children, who might be expected to be more sensitive due to thinner skulls and still-developing brains.
More here:
It is understandable that people are concerned about mobile phones, especially because they are so widely used. But so far, the published studies do not show that mobile phones could increase the risk of cancer. This conclusion is backed up by the lack of a solid biological mechanism, and the fact that brain cancer rates are not going up significantly.
And here:
So we can’t rule out the possibility that mobile phones cause cancer, but it does look pretty unlikely, which is why the IARC has classed it as 2B. This is not an admission that mobile phones cause cancer, it is simply an honest indication that it is impossible at this stage to rule out. It is also, incidentally, pretty much in line with mobile phone guidelines handed out by the UK government since 2000, which is to keep calls short if you are concerned, and try to minimise your children’s use.
But if it turns out, later, that the evidence improves, what does it mean? Well, obviously, since right now the evidence is weak, we don’t know. But one study – and the headline figure, really, that is being bandied around – is that 10 years of heavy mobile phone use could lead to a 40 per cent increase in risk of glioma, a cancer of nervous tissues in the brain or spine. That sounds pretty bad, and, of course, it is. But bear in mind that gliomas, while the most common kind of brain tumour, still have an incidence of between 2.1 and 7.1 per 100,000 head of population per year, according to the Handbook of Clinical Neurology. So even if the headline-grabbing, scary 40 per cent figure is accurate, and the top-level 7.1 per 100,000 per year is also accurate, that leads us to a new level of 10 incidences per 100,000 per year. It’s an increase, but it’s not so terrible when you put it like that.
And here:
It's mildy amusing to note that mobile phone use appears to be prevent brain cancer among people who have ever made a cell phone call. Even among top ten percent of heavy users, their risk of brain cancer was well below Shapiro's 2.0 relative risk threshold.
Interestingly, as the number of cell phone subscriptions in the U.S. has risen from 1 million in 1987 to over 300 million today, the National Cancer Institute reports that brain cancer incidence [PDF] has been trending slightly downward.
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