As I sit here in the Winnipeg airport waiting for my delayed flight on my way home from a great agricultural conference in Saskatoon (Food and Farm Saskatchewan), Im counting the number of people talking on cell phones. Out of about 25 in the vicinity, 11 are on the phone. One girl has been talking since Ive been sitting here, which is about two and a half hours. So it gets me thinking about the age-old question (if you can call two decades or so age-old) about cell phones causing brain cancer. That saga began back in 1993 with an appearance by David Reynard on the Larry King Show. Davids wife had developed a rare type of brain tumour in an area that according to David was very close to where she held her cell phone for long periods. He was convinced that the phone had caused the tumour and sued the manufacturer. The suit was eventually dismissed for insufficient scientific evidence. Since that time we have had a number of studies about the effects of cell phone radiation and one might ask the question if the outcome of the suit would be different today. I dont think so. Exposing human cells to radio frequency radiation in the lab has shown no mutations which would be indicative of carcinogenicity. Experiments exposing animals to such radiation has had no effect. What about people? One study did show a slight increase in glucose metabolism near the position of the cell phone, probably due to heat. But many things including visual stimulation, such as watching for people on cell phones, can cause increased glucose metabolism. Despite the huge increase in the number of cell phones there has been no increase in age-adjusted brain tumours. One Swedish research groups claims to have found a link to brain tumours in people who have used cell phones extensively for over 25 years but the number of tumours is too small to be convincing. And there is the problem of recall bias. People who have brain tumours are likely to exaggerate the time they had spent on the phone because they are searching for an explanation as to why me? The largest human epidemiological study ever carried out, the Interphone trial administered by the World Health Organization found no relationship overall between cell phone use but did come up with a couple of curioisities. Regular uses had a decreased risk when compared with non-users but heavy users had an increased risk in one type of tumour. Recall bias is the likely explanation. What we really need is a study of brain tumour cases and records of exact time spent on cell phones as determined from company data. But such data is not forthcoming. Basically, I have no concern calling home and chatting to my wife about the delay, but I wonder if I should go over and tell the girl that maybe after three hours she should switch to the other ear.
Posted on: Fri, 12 Dec 2014 03:34:29 +0000
Trending Topics
Recently Viewed Topics
© 2015