Sunday, April 02, 2006

Cell phone use raises brain tumor risk

Using a cell phone or mobile phone over a long period raises the risk of malignant brain tumors, according to a new Swedish study published in the International Archives of Occupational and Environmental Health.The study found that heavy users of cell phones increased their risk of a malignant brain tumor on the side of the head the phone is used by 240 percent.By heavy users, the authors referred to those who used a cell phone for 2,000 hours or for one hour a day over a period of more than ten years.
In the current study, researchers at the Swedish National Institute for Working Life compared cell phone use of 2,200 patients with malignant tumors and an equal number of healthy control cases. Among the tumor patients aged 20 to 80, 905 had a malignant brain tumor, one third of them were heavy users of cell phones."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," Reuters quoted the authors of the study in a statement issued by the Institute.
The study may have more say than some previous studies about the effect of cell phones on the risk of brain tumors, according to Kjell Mild, lead author of the current study, because this is the biggest study looking at the long-term effect of the wireless phone. One study published last April by the American Academy of Neurology found no link between use of mobile phones and brain tumors. That study found that the risk of developing a brain tumor was not related to the frequency of cell phone calls or the number of years they had been used.
ne drawback of that study is that few study participants regularly used cell phone for more than 10 years. Short-term exposure to radiation from cell phones and long-term development of a brain tumor may make it impossible for the researchers to see any tumor-causing effect of cell phones in such a study.
Another weakness of the 2005 study is that the participants were "hand-picked". The study is not a population-based cohort study. Bias can not be avoided and the potential risk of cell phone use may be diluted out by other factors.As with other studies of the same type, the current study also has its limitations. For one thing, the study relied on data collected from subjects through interviews, which may be subject to biases and errors when someone recalled his use of cell phones.Dr. Lydia Zablotska, an epidemiologist at Columbia University's Mailman School of Public Health, was quoted by New York Daily News as saying: "You're interviewing subjects in an era when everyone has a suspicion that cell phones may be harmful."Regardless, few scientists may deny the fact that cell phone radiation can damage cells and potentially cause tumors.
What needs to be clarified is how much damage use of cell phones may cause in the brain, which can be quite some task. With the continuing controversy over the safety of cell phone use, it's only prudent for one at least not to overuse cell phone if he can't avoid using cell phones. "The way to get the risk down is to use handsfree," Mild told Reuters.Experts suggest children should avoid using cell phones whenever possible because they are the people who are most vulnerable to the tumor risk than adults.