WHO says mobiles cause cancer?

The mobile phones/cancer link is back in the headlines thanks to the World Health Organization’s International Agency for Research on Cancer (IARC). And as usual, some people are drawing erroneous conclusions.
 
The IARC, having just wrapped up a week-long panel reviewing the studies done so far looking at the possible effects of cell-phone radiation on users, stated that it has “classified radiofrequency electromagnetic fields as possibly carcinogenic to humans (Group 2B), based on an increased risk for glioma, a malignant type of brain cancer, associated with wireless phone use.”
 
Cue the usual headlines with words like “warning” and “concern” and “risk”, as well as the usual rebuttals from mobile industry groups like the GSM Association and CTIA.
 
In reality – and as the GSMA and CTIA point out – the health risk of mobile phones hasn’t been proven to be any greater as a result of the IARC study, which evaluated existing research. The IARC’s conclusion was that there wasn’t enough evidence to draw a definite link between cell-phone usage and certain types of cancer like glioma and acoustic neuroma, but that there was enough evidence to classify cell phone RF under Group 2B in its risk classification system.
 
Here’s what Group 2B means (from the IARC press release):
 
Group 2B: The agent is possibly carcinogenic to humans.
 
This category is used for agents for which there is limited evidence of carcinogenicity in humans and less than sufficient evidence of carcinogenicity in experimental animals. It may also be used when there is inadequate evidence of carcinogenicity in humans but there is sufficient evidence of carcinogenicity in experimental animals. In some instances, an agent for which there is inadequate evidence of carcinogenicity in humans and less than sufficient evidence of carcinogenicity in experimental animals together with supporting evidence from mechanistic and other relevant data may be placed in this group. An agent may be classified in this category solely on the basis of strong evidence from mechanistic and other relevant data.
 
Put another way, the IARC statement says what we’ve already understood for some time now – there’s no solid proof that mobile phones cause cancer, but there’s enough evidence to warrant further study on the long-term effects of mobile phone use for heavy users. 
 
Granted, IARC Director Christopher Wild did add in the statement that, pending the outcome of future studies, “it is important to take pragmatic measures to reduce exposure such as hands‐free devices or texting.” But that’s a far cry from saying, “Cell phones are dangerous – don’t use them.”
 
Meanwhile, Ed Yong of Cancer Research UK has a good breakdown of the IARC statement and the essential context needed to understand it.