Abstract :
Purpose
The wide use of cellular phones has raised public concern for its possible relationship with cancer risk because the radio frequency (RF) exposure from cellular phones has been suspected as a possible carcinogen. However, the data for evaluating the issue is limited especially for the long term effects because only within the past decade has cellular phone use become nearly ubiquitous. Current results from case-control studies for this issue are inconsistent. Recently, a study from the nationwide Danish cohort showed no large association between cellular phone use and cancer risk.
Methods
To evaluate the possible association between cellular phone use and cancer risk, the Danish cohort data has been re-analyzed and the statistical power was estimated.
Results
The results suggested that the Danish cohort data had enough statistical power to detect the weak association (>2% increase) with the overall cancer risk. However, the statistical power for brain (and nerve system) tumors was inconsistent. The cohort data had 94% and 99% power to detect 15% and 20% increase in cancer risk respectively, but the power was sharply reduced to 22% and 66% for 5% and 10% increase in risk for brain tumors respectively. The cohort data did not have enough statistical power to detect a lower increase in risk for brain tumors. Suspected association of the wide use of cellular phones could be small and mainly related to brain tumors; thus, further study is needed for the issue. To assess the possible association with brain tumors, studies with larger population and/or longer follow-up data will be needed.
Conclusion
Overall, there is no evidence to rule out cellular phoneʹs carcinogenic effect for brain tumors yet; the possible increase in risk for brain tumors could be lower. Further studies should be conducted for the issue.
