Falzone N, Huyser C, Frankenc DR, Leszczynskid D. 2010. Mobile phone radiation does not induce pro-apoptosis effects in human spermatozoa. Radiat. Res. 174: 169-176.
Recent reports suggest that mobile phone radiation may diminish male fertility. However, the effects of this radiation on human spermatozoa are largely unknown. Significant genotoxic effects and oxidative stress resulting from RF EMF have been demonstrated in human spermatozoa but it is not known whether apoptosis can be initiated in fully differentiated spermatozoa.
The objective of this study was to examine the effects of radiation on the induction of apoptosis related properties in human spermatozoa.
Semen samples were collected from healthy, non smoking donors (n=12). Ejaculated, density purified, highly motile human spermatozoa were exposed to mobile phone radiation (900 MHz GSM) at specific absorption rates (SARs) of 2.0 and 5.7 W/kg for 1 hour. Directly after the exposure, spermatozoa were incubated under capacitating conditions and examined at different times after exposure: immediately, after 2 hours, and after 24 hours. Flow cytometry was used to examine caspase 3 activity, externalization of phosphatidylserine (PS), induction of DNA strand breaks, and generation of reactive oxygen species.
Caspase activation in 2.0 W/kg RF EMF-exposed sperm did not differ significantly from that in control sperm over the 24-h period (P=0.4). Similarly, at an SAR of 5.7 W/kg, there was no significant difference between caspase activation in RF EMF-exposed and control sperm (P=0.5). No significant differences were seen in the total number of cells with externalized PS and no significant difference (P=0.41) between control cells, and cells exposed at a SAR of 2.0 W/kg directly 2 hours or 24 hours after exposure. For a SAR of 5.7 W/kg, no significant differences between RF EMF-exposed and control cells (P=0.45) were noted directly, 2 hours or 24 hours after exposure. There were no statistically significant differences between control sperm and exposed sperm with respect to DNA fragmentation or in terms of reactive oxygen species generation.
Interpretation and Limitations
Although the effects of mobile phone radiation on human spermatozoa are largely unknown, several studies have shown significant genotoxic effects, oxidative stress and the generation of reactive oxygen species after RF EMF exposure. The role of RF EMF in apoptosis is controversial. The authors found no evidence of any in vitro effect of RF EMF exposure on pro-apoptosis events such as caspase activation, phosphatydylserine expression DNA fragmentation or reactive oxygen species generation in human spermatozoa. The authors suggest that apoptosis is not the mechanism responsible for changes in fertility. One limitation of this study is the small sample size. It is also difficult to extrapolate the results at the organismal level therefore; in vivo experimentation may produce different results.