Round-the-clock cell phone radiation may harm growing brains, a mouse study suggests. Mice exposed to an active phone for the duration of a pregnancy gave birth to pups that displayed long-lasting behavioral and brain abnormalities, researchers write March 15 in Scientific Reports
Although the results indicate that chronic exposure to cell phone radiation can disrupt the fetal brain in mice, it's unclear whether the same holds true for people. "The paper is an interesting paper. There are no two ways around that," says Nora Volkow, director of the National Institute on Drug Abuse in Bethesda, Md., who has studied the effects of cell phone radiation. "The issue is, ultimately, what is the significance to humans?"
In the study, reproductive endocrinologist Hugh Taylor of Yale School of Medicine and colleagues rigged up bare-bones cell phones (not smart phones) to pregnant mice's cages. Half the phones were actively receiving a call on mute for the entirety of the mice's pregnancies, which last about 17 days. The other phones were inactive.
On average, offspring from the mothers exposed to cell phone radiation performed worse on a memory test, moved around more, and were less anxious than mice who were not exposed to cell phone radiation. Nerve cell signaling in the prefrontal cortex - a brain region that, in humans, sits behind the forehead and has been implicated in many mental disorders - was also dampened in exposed mice.
In the report, Taylor and his colleagues suggest that these behavioral and brain deficits are similar to those seen in people with attention-deficit/hyperactivity disorder, and speculate that increased cell phone use could explain an increase in ADHD in children.
Other scientists disagree. "To blame the increase in ADHD on mobile phones, that is premature," says cognitive neuroscientist and ADHD researcher Katya Rubia of King's College London, who says that such a claim is alarmist and unjustified. The behavioral deficits of the mice are very different from the behavioral symptoms seen in people with ADHD, she says.
Mouse fetuses in the experiment were between 4.5 and 22.3 centimeters from the phone at all times - creating a different exposure than what a human fetus would receive. And Volkow notes that human fetuses have more protective amniotic fluid around them. "The exposures were too high and too intense to be translated to humans," she says.
So far, other research has hinted at a possible link between pregnant women who used cell phones frequently and behavioral problems in their children. Two studies, led by epidemiologist Hozefa Divan, who conducted the research at UCLA and at the University of Southern California in Los Angeles, found such an association. But more studies are needed, he says. "There's still a lack of really solid evidence one way or the other."
In the meantime, the researchers agree that pregnant women should avoid carrying a cell phone near the abdomen. "I don't want to sensationalize this or cause panic, but I think it's worth being cautious," Taylor says.