A large new study finds no link between long-term use of mobile phones and brain or central nervous system cancer. The research appears on bmj.com. In what is described as the largest study on the subject to date, Danish researchers found no evidence that the risk of brain tumors was raised among more than 350,000 mobile phone subscribers over an 18-year period.
We asked Elizabeth Ward, PhD, National Vice President, Intramural Research, to comment on the study.
“This large Danish study of mobile phone subscribers adds to the body of evidence regarding cell phone use and brain cancer. The study found no increased risk of central nervous system tumors among mobile phone subscribers compared to the general population. The strengths of this study include its large size (358,403 telephone subscribers), ascertainment of cell phone “exposure” from mobile phone subscription records rather than participant recall and ascertainment of brain tumor cases from a very complete national cancer registry. The most significant weakness of the study is that subscription to a mobile telephone does not necessary indicate exposure (for example, one family member may subscribe to a cell phone that other family members use) and there is no data on frequency or duration of use. Other limitations of the study include a maximum duration of exposure it fifteen years, does not address potential effects among children, and did not address parotid gland tumors which have been suggested as caused by cell phones.
“The authors of the study acknowledge that miss classification of exposure may have biased their study towards a negative finding, but conclude that the results can be used to rule out moderate to large risks associated with mobile phone use.
“The bottom line is that, at this point, there is not strong evidence for an association between cell phone use and cancer in humans. This study will not quell all concerns about this issue. However, those who are concerned about this electromagnetic field exposure can reduce it by using earpieces. In addition, it is important for the public to be aware that the primary documented risk of cell phones continues to be their association with vehicle accidents. “