Otitoloju AA, Obe IA, Adewale OA, Otubanjo OA, Osunkalu VO. Preliminary study on the induction of sperm head abnormalities in mice, Mus musculus, exposed to radiofrequency radiations from Global System for Mobile communication base stations. Bull Environ Contam Toxicol. Ahead of print. Oct 9, 2009.
Some, but not all studies have found that low level radiofrequency (RF) radiation is associated adverse biological effects. A number of countries have set exposure safety limits, but they vary between countries and reflect differences in how mobile phone risk is perceived.
The objective of this study was to determine the effects of RF exposure from mobile phone base stations on sperm head abnormalities in mice.
Three locations were selected for the experiment. The first contained 2 GSM mobile phone base stations and was located in a residential neighbourhood, the second contained 1 base station and was located in an office block complex, and the third was a control site with no base stations within a 300m radius. Cages containing 5 male mice each were placed underneath mobile phone base stations for 6 months, over which time RF field strength at the sites was also measured. Mice were euthanized and their sperm was examined under a microscope.
The mean percent of sperm with head abnormalities was 2.13% in the control group, compared to 46.03% in the first exposure site (residential neighbourhood) and 39.78% in the second exposure site (office complex). The difference between the exposure and control site was statistically significant. The main abnormalities observed were sperm head with knobbed hook, pin-head, and banana-shaped head. The frequency of sperm head abnormalities was positively associated with the RF radiation levels at the test locations, suggesting that the occurrence of sperm head malformations is dose-dependent.
Interpretation and Limitations
Sperm head formation is genetically controlled. Therefore, damage to sperm DNA may result in malformations. Several studies have related large doses of RF radiation to genetic defects. The authors suggest that RF radiation may have damaged sperm DNA, resulting in malformations. The authors also suggest invoking the precautionary principle (“better safe than sorry”) in dealing with the potential health risks of mobile phones. The limitation of this study is the small sample size. It is also difficult to extrapolate the results to humans.
This study suggests that long-term exposure to RF radiation is associated with sperm head malformations in mice.