This is a link to an article investigating leukemia rates in areas near AM
transmitters.

http://www.wired.com/news/medtech/0,1286,64579,00.html

I don't doubt that high levels of RF can be dangerous. The first two chief
engineers I worked with both died of cancer in their 50s.

Maybe they got cancer from some other cause (both smoked), but I still feel
like I'm inside a microwave oven anytime I'm around an AM transmitter site.