Danish study finds no evidence of causal link between mobiles and cancer
by Dr Windsor Holden on October 21st, 2011
Ladies and gentlemen, you’ll be pleased to know that the hours that you’ve spent calling and texting and browsing over the past months and years are unlikely to give you brain cancer.
Or, let me rephrase that: there appears to be no direct correlation between spending your life with an iPhone clamped to your ear and an earlier than anticipated one-way trip to the Hereafter.
For the past 18 years, Dr Patricia Frei and her colleagues at Institute of Cancer Epidemiology in Denmark have been conducting a study of nearly 360,000 Danes aged 30 or over (or, to put it another way, more than 10% of the country’s residents who fell into that demographic). This study looked at levels of incidence of tumours of the central nervous system, and participants were subdivided into two groups: those who subscribed to mobile phones before 1995, and those who did not. The crucial finding of Frei et al was simple: for the phone subscribers, “there were no increased risks of tumours of the central nervous system, providing little evidence for a causal association.”
Of course, this does not prove that there is no such association, but proof is notoriously hard to come by: as David Hume pointed out, we expect that the sun will come up tomorrow morning, but we can’t prove that it will on the basis that it did so today and yesterday and every day before that. What it does is demonstrate that such an association is that much less likely, providing one more piece of evidence for the defence.
As things stand, electromagnetic fields produced by mobile handsets are classified as “possibly carcinogenic” (category 2B) by the International Agency for Research on Cancer: this classification is primarily – but by no means exclusively – based on a large-scale study, Interphone, conducted by the agency and published earlier this year. While the study (like Dr Frei’s) “found no increased risk of glioma or meningioma with mobile phone use of more than 10 years”, it did observe “some indications of an increased risk of glioma for those who reported the highest 10% of cumulative hours of cell phone use, although there was no consistent trend of increasing risk with greater duration of use” (my italics). Hence the “possibly carcinogenic” categorisation, an appellation that mobile handsets share – for the time being at least – with bedfellows ranging from coffee to gasoline, from phenobarbital to (I am not making this up) pickled vegetables.
I am not entirely sure of the IARC’s delisting process as far as carcinogens are concerned: nor does there appear to be a 2C category into which “possible carcinogens” could be reclassified as “faintly possible carcinogens”. Thus, mobile phone use will remain in 2B for the time being; but the case for the defence will continue to grow stronger.
So, I will continue to use my mobile phone in good heart and, hopefully, good health.
(Furthermore, I don’t like coffee, so I’m in the clear on that one…)
Tags: electromagnetic radition, mobile handsets, mobile networks
