Study Says RF From AM Stations Could be Hazardous, Others Say No is reporting Korean scientists have found greater incidence of leukemia and other cancer deaths near AM radio-broadcasting tower. The details are in the Wired article Is AM Radio Harmful? by Stephen Leahy.
The article quotes Mary McBride an epidemiologist at the British Columbia Cancer Agency saying the studies aren't very convincing and many other factors could have contributed to the increase in cancer rates. An American Journal of Epidemiology article suggested there was an association between lymphatic and hematopoetic cancers and residential exposure to RF fields based on a study of the cancer rates in people living near the Vatican Radio transmitter sites. Also see the article Electromagnetic radiation - Environmental pollution and health in the British Medical Bulletin.
I should note that most studies show the only effect of non-ionizing RF energy on people is related to the over-heating it can cause in the body, although one study I described in the December 6, 1999 RF Current showed exposure to microwave energy had an impact on long-term memory in rats.