Features

CHICAGO — A study of people who used cell phones for an average of less than three years found no evidence the devices cause brain cancer. 

The research does not answer the question of whether longer-term use is dangerous. 

The study, funded by the industry group Wireless Technology Research and the National Cancer Institute, appears in Wednesday’s Journal of the American Medical Association. 

The study of 891 people did find a slightly increased risk for a rare type of brain cancer, but the researchers said it was not statistically significant. 

While they acknowledge longer-term studies are needed, the researchers said the overall results should reassure the more than 86 million cell phone users nationwide. 

“We feel confident that the results reflect that cell phones don’t seem to cause brain cancer,” said epidemiologist Joshua Muscat, a scientist at the American Health Foundation who helped lead the study. 

Publication of Muscat’s research prompted the New England Journal of Medicine to release a study Tuesday showing similar results. The study, led by National Cancer Institute researchers and set for publication on Jan. 11, looked at 782 brain cancer patients and 799 people without cancer. 

Maximum cell phone use was at least an hour per day for five or more years, and no brain-cancer link was found even at that level.  

The authors of the second study said longer-term use needs more study. 

Unlike regular telephones, handheld cell phones contain an antenna inside the receiver, which puts the user’s brain close to the electromagnetic radio waves the antenna emits. Since cell phones were introduced in the United States in 1984, conflicting data have emerged from safety studies on animals and humans. 

The Food and Drug Administration has said there is no evidence that the phones are unsafe, but it has joined with the wireless industry in sponsoring research on the devices. Some cell phone makers have also started disclosing their products’ radiation levels. 

The JAMA study, co-written by Dr. Mark Malkin of Memorial Sloan-Kettering Cancer Center in New York, involved phone-use questionnaires given to 469 men and women ages 18 to 80 with brain cancer and a 422-member cancer-free control group. 

Cell-phone use was slightly more common among the cancer-free participants, though average cell-phone use for both groups was under three hours monthly for less than three years. 

The amount and duration of cell-phone use were not related to an increased brain cancer risk except for a type of neuron-cell tumors called neuroepitheliomatous cancer. Of the 35 patients with these rare tumors, 14 – 40 percent – used cell phones. 

“An isolated result like that can occur entirely due to chance,” said Russell Owen, chief of the FDA’s radiation biology branch. He said the overall findings are in line with previous research and “certainly not cause for concern.” 

The Cellular Telecommunications & Internet Association said in a statement that it welcomes the JAMA findings and noted that its collaboration with the FDA will produce additional research into safety questions. 

Professor Henry Lai of the University of Washington, whose animal research linked cellular phone signals with cell damage in rat brains, called the JAMA study “very preliminary and inconclusive.” 

“Since most solid tumors take 10 to 15 years to develop, it is probably too soon to see an effect,” Lai said. 

——— 

On the Net: 

http://jama.ama-assn.org 

http://www.fda.gov/cdrh/radhealth.html 

http://www.nejm.org