Researchers have found no consistent link between cell phone use and the risk of developing brain cancer, but experts speaking at a recent AAAS briefing on Capitol Hill said science faces a communications challenge in dispelling the public’s lingering fears.
George M. Gray, a professor and director of the Center for Risk Science and Public Health at George Washington University, noted that concerns about cell phones have persisted in part because the public has received mixed messages. At the 7 September briefing organized by AAAS’s Office of Government Relations and supported by the Dana Foundation, Gray said people want to understand both the cause of the concern and “how big a problem” they face in assessing health risks.
Radiofrequency electromagnetic energy, such as the waves emitted by cell phones, clearly do not damage DNA in cells, which, were it true, might in turn cause cancer. According to the U.S. National Cancer Institute, studies so far “have not shown a consistent link between cell phone use and cancers of the brain, nerves, or other tissues of the head or neck.”
But the International Agency for Research on Cancer classified such radiofrequency fields as “possibly carcinogenic,” based on an increased incidence of glioma, a malignant brain cancer. That classification represented “the weakest result they could come to,” without clear evidence to disprove a connection, Gray said, yet the terminology may confuse people.
Adding confusion has been the fact that different types of studies have yielded different results about the overall effects of cell phone use, said Nora Volkow, director of the U.S. National Institute on Drug Abuse. Studies examining cognitive abilities, cerebral blood flow, or the brain’s electrical activity before and after cell phone exposure have been inconsistent.
Volkow’s research has revealed increased brain glucose metabolism following cell phone use, but she stressed that it is unclear whether this change is harmful. Amid uncertainty, she suggested minimizing risks by using hands-free devices, sending text messages, selecting phones with antennas at the bottom, and limiting children’s use of cell phones. Additional research is needed to clarify the long-term effects of cell phone use, she said.