Since the first Gordon Gekkos of the world picked up their 10-pound brick mobile phones more than two decades ago, there have been numerous studies into the relationship, if any, between mobile phone use and cancer. And it’s a debate that won’t disappear anytime soon thanks to the World Health Organization’s announcement that it has categorized wireless phone use as “possibly carcinogenic to humans.”

The WHO’s International Agency for Research on Cancer issued a statement earlier today saying that it had recently convened a working group of 31 scientists from 14 countries to comb through research on the topic of exposure to radiofrequency electromagnetic fields.

The results of their investigation:

The evidence was reviewed critically, and overall evaluated as being limited among users of wireless telephones for glioma and acoustic neuroma, and inadequate to draw conclusions for other types of cancers. The evidence from the occupational and environmental exposures mentioned above was similarly judged inadequate. The Working Group did not quantitate the risk; however, one study of past cell phone use (up to the year 2004), showed a 40% increased risk for gliomas in the highest category of heavy users (reported average: 30 minutes per day over a 10-year period).

But before you go looking for a lead-lined iPhone case, the IARC findings classified the level of risk as:

[One] 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.

From the IARC director:

Given the potential consequences for public health of this classification and findings, it is important that additional research be conducted into the long-term, heavy use of mobile phones. Pending the availability of such information, it is important to take pragmatic measures to reduce exposure such as hands-free devices or texting.

See the entire PDF here.

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