Heavy users of wireless mobile phones face increased risks of developing severe brain tumors, according to the most comprehensive study ever conducted on the possible link between cancer and the long-term use of cellular telephones.
Researchers at the Swedish National Institute for Working Life and the University of Oerebro compared the mobile phone use of 4,400 people—half of them cancer patients, and the other half healthy people who made up the control group—and made some disturbing discoveries. [The U.S. Food and Drug Administration has since questioned the results of this study. For information, see FDA Questions Results of Study Linking Mobile Phones and Cancer.]
Heavy Mobile Phone Use Increases Cancer Risk
According to Kjell Hansson Mild, who led the study, heavy users of mobile phones have a 240 percent increased risk of developing a malignant tumor on the side of the head where they press the phone to their ear.
Published in the International Archives of Occupational and Environmental Health, the study defines “heavy use” as 2,000 hours of mobile phone use in the course of a decade, which "corresponds to 10 years' use in the work place for one hour per day."
Of the 2,200 cancer patients in the study, who ranged in age from 20 to 80 years old, 905 had a malignant brain tumor and just under one-tenth of that number were heavy mobile phone users.
"Of these 905 cases, 85 were so-called high users of mobile phones, that is they began early to use mobile and/or wireless telephones and used them a lot," said the authors of the study in a statement issued by the Institute.
In addition, the study concluded that early users, defined as people who started using a mobile phone before age 20, are also at greater risk of developing a malignant brain tumor.
The study also took into account factors such as smoking habits, working history and exposure to other known cancer-causing agents.
Limit Mobile Calls and Use Handsfree Options
Hansson Mild advised that the best ways for consumers to lower their risk of cancer related to mobile phones are to use their wireless phones less frequently and to use handsfree options when they do make or receive mobile calls. He said the research report about the study is not intended to cause public alarm or to raise concerns about widespread risk for the majority of people who use mobile phones.
"It does however give reason to use caution when calling on wireless phones,” he said in an interview with Dow Jones. “Use handsfree and avoid wireless when possible.”
Swedish Study Breaks New Ground
The Swedish study is the first to show a significant link between long-term mobile phone use and cancer. Previous studies found no evidence that radiation from mobile phones is harmful, but those earlier studies looked at mobile phone use among fewer people over a shorter time.
The Swedish study is the largest and most comprehensive to date. Also, people in Sweden have been using mobile phones since 1984, longer than people in many other countries, so getting a large sample of people who have been using cellular telephones for a long time was relatively easy.