300% Increased Brain Cancer Risk For Long-term Users Of Cell Phones And Cordless Phones, New Study Revealed.
There is insufficient information to definitively say whether or not wireless phones increase brain cancer risk. Available studies show an association between mobile and cordless phone use and malignant tumors, but have not proven that the wireless phone technology is directly responsible for the increased brain cancer risk.
Press release distribution sites have warned cell phone users of an increased risk of brain tumors in people who use wireless phones for 25 years or longer.
Cell phones and cordless phones emit a form of electromagnetic radiation which can be absorbed by adjacent tissues and cells. In 2011 the International Agency for Research and Cancer (IARC) classified radio frequency electromagnetic radiation as Group 2B risk i.e. possible human carcinogens.
Nordic countries were among the first countries worldwide to adopt wireless technology widely. One of the Nordic countries, Sweden, has a National Cancer Register which covers the six main administrative medical regions. This makes Sweden an ideal venue for studying the possible link between long-term mobile/cordless phone use and cancer.
Swedish investigators published a study (1) in the International Journal of Oncology in 2013 which looked at the possible link between malignant brain tumors and mobile/cordless phone use.
Drs. Hardell and Carlberg carried out a case control study of all newly diagnosed malignant brain tumors in men and women (between the ages of 18 and 75) between the years 2007 and 2009. A total of 1334 cases of brain cancer were reported over this time period. For the purposes of this study, cases of malignant brain tumor were limited to histopathologically confirmed cases and not just cases with a clinical or radiological suspicion of a diagnosis of brain cancer.
Glioblastoma multiforme was the most common form of brain cancer diagnosed, and the average survival time from the diagnosis of brain tumor was less than a year.
People who were confirmed to have a malignant brain tumor were initially asked to fill out a written questionnaire. They also participated in a follow-up telephone interview to clarify any areas of uncertainty in the written questionnaire.
The study showed a statistically significant increased risk of malignant brain tumors associated with the use of wireless phone technology. People who use cell phones for more than 25 years had a 300% increased risk of developing a malignant brain tumor. The risk of developing a brain tumor was greatest on the side of the head that was preferred for listening and talking while using a cell phone.
The key limitation of the study was the fact that it was difficult to find people who do not use cell phone technology to act as controls. Some statistical manipulation was used to correct for this shortage of non-cell phone users.
Another limitation is the study was the fact that actual wireless phone usage and phone minutes were not verified and cross-checked with the cell phone provider.
There is no agreed biological mechanism by which radio frequency electromagnetic radiation produces changes in the DNA and cancer.
The authors of the study conclude that they showed, ‘An association between mobile/cell phone use and malignant brain tumors’ and that this ‘provides support for the hypothesis that radio frequency electromagnetic radiation plays a role in carcinogenesis’
In summary, this study shows an association between wireless phone use and brain tumors but does not prove that the wireless phones are directly responsible for the increased risk of brain tumors.
- Int J Oncol. 2013 Dec; 43(6): 1833–1845. Published online 2013 Sep 24. doi: 10.3892/ijo.2013.2111 PMCID: PMC3834325 Case-control study of the association between malignant brain tumours diagnosed between 2007 and 2009 and mobile and cordless phone use LENNART HARDELL,1 MICHAEL CARLBERG,1 FREDRIK SÖDERQVIST,1,3,4 and KJELL HANSSON MILD2