Background: Whether exposure to common electromagnetic fields affects human health adversely has been a controversial issue. The main goal of this study was to assess the role of 900 MHz microwave radiations with different specific absorption rates (SARs), emitted from some widely used cell phones, on the induction of adaptive response in male Balb/c mice after receiving a lethal dose of gamma radiation. Materials and Methods: This study was conducted on 120 male Balb/c mice. The animals were divided into groups of 20 mice each (6 groups). Group one (the control group) received neither microwave radiation nor the lethal dose of gamma radiation. Group two was exposed only to the lethal dose of 8.8 Gy. The mice in group three were first exposed to low SAR 900 MHz microwave radiations emitted from a cell phone for six hours (3 hours in the morning and 3 hours in the afternoon) for 5 days and then were exposed to a lethal dose of 8.8 Gy on day six. The mice in group 4 were treated as those in group 3 but with a moderate SAR and the mice in group 5 were also treated as those in groups 3 and 4 but with a high SAR. The mice in group six were exposed only to high SAR 900 MHz microwaves. Results: All groups were monitored for 12 days and their daily mortality rates were recorded. The results showed that there was a statistically significant difference between group two (the animals exposed only to lethal dose of gamma radiation) and the groups with a pre-exposure to microwave radiations before receiving the lethal dose. Conclusion: To the best of our knowledge, this is the first study that investigates the role of SAR on the induction of microwave-induced survival adaptive response. It can be concluded that 900 MHz microwaves emitted from cell phones, regardless of their SAR can induce adaptive responses which make the animals more resistant to subsequent lethal doses of ionizing radiation. These findings also confirm our preliminary findings obtained in a previous study.

Background: The health effect of rapidly increasing everyday exposure of humans to radiofrequency radiation is a major global concern. Mobile phone jammers prevent the mobile phones from receiving signals from base stations by interfering with authorized mobile carriers’ services. In spite of the fact that mobile jammer use is illegal, they are occasionally used in offices, shrines, conference rooms and cinemas. The purpose of this study was to investigate the biological effects of short term exposure of human sperm to radiofrequency radiation emitted from a commercial mobile phone jammer. Materials and Methods: Fresh semen samples were obtained by masturbation from 50 healthy donors who had referred with their wives to Infertility Treatment Center at the Mother and Child Hospital, Shiraz University of Medical Sciences. Female problem was diagnosed as the reason for infertility in these couples. The semen sample of each participant was divided into 4 aliquots. The first aliquot was subjected to swim-up and exposed to jammer radiation. The second aliquot was not subjected to swim-up but was exposed to jammer radiation. The third and fourth aliquots were not exposed to jammer radiation but only the 3^rd aliquot was subjected to swim-up.  Results: Semen samples exposed to radiofrequency radiation showed a significant decrease in sperm motility and increase in DNA fragmentation. Conclusion: Electromagnetic radiation in radiofrequency range emitted from mobile phone jammers may lead to decreased motility and increased DNA fragmentation in human semen. It can be concluded that mobile phone jamming might exert adverse reproductive health effects.