I should note in response to several good replies here, that since cell phone usage varies by country and demographic, it seems that if it caused a (significant

I should note in response to several good replies here, that since cell phone usage varies by country and demographic, it seems that if it caused a (significant) increase in brain cancer (the organ most exposed to cell phone related radiation), it would show up in a distinctive pattern. Japan had widespread cell phone usage before the U.S.A., and in the US the upper class had widespread cell phone usage before the working class. If it were a significant factor that ought to stand out from the background noise of other possible carcinogens.