Whether or not cell phones cause brain cancer is a question that's been debated (but not answered) for years, and today the World Health Organization (WHO) stepped into the fray. A WHO committee that evaluates various potential cancer-causing agents concluded that radiofrequency electromagnetic fields, including cell phones, are "possibly carcinogenic" to people. The announcement was seized upon and published in dozens of news outlets within minutes.
The International Agency for Research on Cancer (IARC) arrived at the conclusion of possible carcinogenicity after an 8-day review of the literature by 31 experts, in Lyon, France. The classification falls in the middle of IARC's hierarchy of risk, joining a group of more than 250 potential carcinogens that also includes lead, engine exhaust, and occupational exposure to dry cleaning. In a sign of how tough it is to determine that something doesn't cause cancer, just one of the 900 or so agents that IARC has evaluated, caprolactam, a component of fibers and plastics, falls in the "probably not carcinogenic" category.
When it comes to cell phones, "we found some threads of evidence telling us how cancer might occur, but I think there are acknowledged gaps and uncertainties," said Jonathan Samet, chairperson of the IARC Working Group and a physician and public health expert at the University of Southern California in Los Angeles, during a press conference. The working group was particularly influenced by an international study called Interphone that's examining whether exposure to radiofrequency electromagnetic fields from cell phones causes cancer. Last year, the Interphone study group wrote in the International Journal of Epidemiology that it saw "no increase in risk of glioma or meningioma." It continued: "There were suggestions of an increased risk of glioma at the highest exposure level, but biases and errors" make it tough to show that the phones were the cause. "The possible effects of long-term heavy use of mobile phones require further investigation," they concluded.