Cell phones and cancer risk: an update 7/11
(This article is adapted from ConsumerReportsHealth.org.)
More details were revealed by the group of scientists at the World Health Organization's International Agency for Research on Cancer (IARC), which has classified low-level radiation from cell phones as "possibly carcinogenic to humans."
In a report published online in The Lancet Oncology, the scientists have clarified how they arrived at their conclusions.
The panel of 30 scientists from 14 countries reviewed hundreds of articles, including animal research and human studies, some of which had methodological limitations or provided inconsistent results. The new report cites some key studies, including the 2010 INTERPHONE study, the largest investigation so far of cell phone use and brain tumors.
The INTERPHONE data showed that people who used cell phones appeared to be at a slightly lower risk, overall, of developing glioma, a type of brain cancer, than those who never used cell phones. However, in that same study, the top 10 percent of cell phone users in terms of call time (total exposure 1,640 hours and over) had a 40 percent increased risk of glioma compared with those who never used cell phones.
The findings also suggested an increased risk for tumors on the side of the head where the phone was held, and in the brain's temporal lobe, where exposure to cell phone radiation is highest.
In their new article, the scientists also cited Swedish research published in 2011, that showed an increased risk for glioma with the use of cell phones for more than 10 years. The risk was highest in subjects who first used cell phones before age 20.
Although the INTERPHONE and Swedish studies are susceptible to bias-due to selection of subjects and errors in recall about cell phone use—the scientists said they could not dismiss the findings. They concluded that a "causal interpretation" between exposure to cell phone radiation and glioma is possible.
The new report also noted that those studies drew a "similar" conclusion for acoustic neuroma, a non-cancerous tumor, although the case numbers were substantially smaller than for glioma. Moreover, a study from Japan has found some evidence of an increased risk for acoustic neuroma associated with the same side of the head as cell phone use.
What you can do to minimize possible risks
Until further research provides clear findings, if you're concerned about radiation risks, Consumer Reports health experts recommend that you can minimize exposure: 1) by using a speakerphone or hands-free headset; 2) by holding the phone away from the head and body (especially when a call is connecting); 3) by texting rather than voice messaging; and 4) by reducing use, especially by children.
What the federal government is doing
Phone manufacturers are required by federal law to package every cell phone with information about its specific absorption rate (SAR) values. The higher the SAR value, the more radiation the body absorbs. But there's usually no explanation provided with those numbers, not even the fact that all phones sold have levels lower than what the federal Food and Drug Administration considers a concern.
In September 2010, the Federal Communications Commission (FCC) revised its Web page to address some of the confusion about SAR values. The updated FCC fact sheet (www.fcc.gov/cgb/consumerfacts/sar.html) states that SAR values indicate the maximum possible exposure from a given phone, not the varying levels of exposure in normal use. So a phone with a lower reported SAR value isn't necessarily safer than one with a higher value, and SAR values can't be used to reliably compare cell-phone models. The FCC says it requires SAR values only to ensure that maximum radiation exposure falls below the level at which experts agree there could be adverse health effects.
The consensus among the experts is that that more research is needed to identify potential risks, especially to children and over longer-term use. Consumers Union believes a number of additional measures would benefit consumers now:
• The U.S. needs a national research program on cell phones and health. Rep. Kucinich has called for such an effort as part of his cell-phone safety proposals. Bottom line
• The FDA and the FCC should step up their efforts to provide better and more visible guidance to consumers on the risks, if any, of cell-phone radiation.
• The FCC should mandate that the SAR information included with phones be more consistent. The information that's currently provided varies greatly in its format and details.
The IARC action is based on limited evidence and doesn't convincingly link typical cell-phone use with cancer. But it does underscore the need for further study, as well as better and more visible guidance to consumers on the issue.
National Cancer Institute Fact Sheet: Cell phones and Cancer Risk. 6/11
Saferphonezone.org from Environmental Health Trust
Cell-phone radiation 'possibly carcinogenic'. 6/11
Cell phones alter brain function, but health effects still unknown. 2/11
How risky is cell-phone radiation? 1/11
FCC Guide: Specific Absorption Rate (SAR) For Cell Phones: What It Means For You.