The Cellular Telephone and its Discontents
The authors of the study compared the incidence of brain tumor in 358,403 Danish subscribers to cellphones with that of people of the same age who did not subscribe. There was no increase in such tumors among subscribers, and just as importantly there was no evidence of a dose-response curve among them: that is to say, a higher rate of tumor development the longer people had subscribed.
There were minor limitations to the study; for example it was assumed that subscribers used phones and non-subscribers did not, so that some people might have been wrongly classified. But this is unlikely to have affected the result very seriously.
It is impossible to prove a negative conclusively, of course, and cellphones have been in widespread use only for twenty years. There are some cancers whose latency -- the period between exposure to cause and the development of the tumor -- is longer than twenty years. It is possible, therefore, that an association will appear one day between the use of cellphones and the development of brain tumor; so far, however, such an association has not appeared, and in Sweden, where nearly 90 per cent of the population has had a cellphone from a very early stage of the technology, national rates of brain tumor have not risen.
Just because cellphones do not harm brains physically, however, does not mean that they do not do other forms of harm. So I say to users of cellphones: improve the average quality of human communication, do not make that call.
(Thumbnail on PJM homepage created using multiple Shutterstock.com images.)