Lehrer S, Green S, Stock RG. Association between number of cell phone contracts and brain tumor incidence in nineteen U.S. States. J Neurooncol. Jun 30 2010. Ahead of print.
In view of the growing number of cell phone users, there is a concern about adverse health effects, in particular the possibility that radiofrequency radiation emitted by cell phone antennas can cause brain tumors or accelerate their growth. Results of studies conducted by different groups of researchers have produced inconsistent results.
The objective of this study was to examine “the relation of cell phone subscriptions to brain tumor incidence by U.S. state.”
The data were obtained from the following sources: reports on brain tumor incidence 2000-2004 and population from 19 U.S. states; 2007 cell phone subscriber data from the Governing State and Local Sourcebook; mean population age and income by state 2004-2006 from census data. Multiple linear regression analysis was conducted with number of brain tumors as a dependent variable, cell phone subscriptions, population size, mean age and income as independent variables.
Results and Interpretation
There was a significant linear relationship between cell phone subscriptions and brain tumor incidence (p=0.017). Tumor type was not taken into account in the analysis, which the authors consider a weakness of their study. Also, it would be useful to see if similar linear relationships exist for each individual state to exclude the possibility that the apparent trend is due to “a disproportionate and disparate increase in the state of NY only.” The authors suggest that the increase in the number of subscriptions might be mainly due to increasing number of children using cell phones, but not adults. They refer to results of a study indicating high risk of acoustic neuroma and astrocytoma in persons who started using a cell phone under 20 years of age.
The authors have concluded that the observed linear relationship needs further epidemiological evaluation. They believe that at this time “it would be prudent to limit exposure to all sources of electro-magnetic radiation”