The World Health Organization's International Agency for Research (IARC) today classified radiofrequency electromagnetic fields use as "possibly carcinogenic to humans" because it increases the risk for glioma, a malignant type of brain cancer.

The WHO says human exposure to radiofrequency electromagnetic fields can occur from occupational exposures to radar and to microwaves; environmental exposures associated with transmission of signals for radio, television and wireless telecommunication; and personal exposures associated with the use of wireless telephones.

The classification change came after a working group of 31 scientists from 14 different countries met to review scientific papers investigating exposure to radiofrequency electromagnetic fields.

The group found no evidence that occupational and environmental exposures was carcinogenic, however, the group did find enough evidence to suggest that mobile phone usage represents a group 2B ( possibly carcinogenic to humans) risk.

In a written statement, Dr Jonathan Samet, chairman of the Working group said that "the evidence, while still accumulating, is strong enough to support a conclusion and the 2B classification. The conclusion means that there could be some risk, and therefore we need to keep a close watch for a link between cell phones and cancer risk."

While the findings are not definitive, the sheer number of wireless phone users worldwide argues for more research and reducing exposure. Said IARC Director Christopher Wild, "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. "

CTIA, a trade group representing the interests of the wireless telecommunications industry, responded to the release by saying "This IARC classification does not mean cellphones cause cancer. Under IARC rules, limited evidence from statistical studies can be found even though bias and other data flaws may be the basis for the results."

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