Induction of Adaptive Response in Human Blood Lymphocytes Exposed to Radiofrequency Radiation

Abstract

The incidence of micronuclei was evaluated to assess the induction of an adaptive response to non-ionizing radiofrequency (RF) radiation in peripheral blood lymphocytes collected from five different human volunteers. After stimulation with phytohemagglutinin for 24 h, the cells were exposed to an adaptive dose of 900 MHz RF radiation used for mobile communications (at a peak specific absorption rate of 10 W/kg) for 20 h and then challenged with a single genotoxic dose of mitomycin C (100 ng/ml) at 48 h. Lymphocytes were collected at 72 h to examine the frequency of micronuclei in cytokinesis-blocked binucleated cells. Cells collected from four donors exhibited the induction of adaptive response (i.e., responders). Lymphocytes that were pre-exposed to 900 MHz RF radiation had a significantly decreased incidence of micronuclei induced by the challenge dose of mitomycin C compared to those that were not pre-exposed to 900 MHz RF radiation. These preliminary results suggested that the adaptive response can be induced in cells exposed to non-ionizing radiation. A similar phenomenon has been reported in cells as well as in animals exposed to ionizing radiation in several earlier studies. However, induction of adaptive response was not observed in the remaining donor (i.e., non-responder). The incidence of micronuclei induced by the challenge dose of mitomycin C was not significantly different between the cells that were pre-exposed and unexposed to 900 MHz RF radiation. Thus the overall data indicated the existence of heterogeneity in the induction of an adaptive response between individuals exposed to RF radiation and showed that the less time-consuming micronucleus assay can be used to determine whether an individual is a responder or non-responder.

Increased Radioresistance to Lethal Doses of Gamma Rays in Mice and Rats after Exposure to Microwave Radiation Emitted by a GSM Mobile Phone Simulator

“…lethal dose of gamma radiation in our study versus chemical agent of mitomycin C in the study by Sannino et al (2009) and the endpoint; i.e. survival rate, 30 days after LD 50/30 in our study versus induction of micronuclei in the study by Sannino et al (2009).…”

“…The cardinal differences between our study and that conducted by Sannino et al (2009) include the type of the challenge dose ; i.e. lethal dose of gamma radiation in our study versus chemical agent of mitomycin C in the study by Sannino et al (2009) and the endpoint; i.e. survival rate, 30 days after LD 50/30 in our study versus induction of micronuclei in the study by Sannino et al (2009).…”

Window Theory in Non-Ionizing Radiation-Induced Adaptive Responses

“…On the other hand they reported that they had previously conducted a preliminary experiment to determine the minimum power density for RF pre-exposures to minimize the damage induced by subsequent exposure to DOX. We and other investigators have previously reported that radiofrequency radiation can induce adaptive response phenomena (Haghani et al 2012;Jiang et al 2012;Mortazavi et al 2011;Mortazavi et al 2012;Sannino et al 2009;Zeni et al 2012). Jin's findings as well as findings obtained in our studies (Mortazavi et al 2012) clearly support the dose window theory that is well discussed for adaptive responses induced by ionizing radiation.…”

Induction of adaptive response: Pre-exposure of mice to 900 MHz radiofrequency fields reduces hematopoietic damage caused by subsequent exposure to ionising radiation

“…In this context, Markkanen et al (2008) have reported that pre-exposure of murine L929 cells to 50 Hz magnetic fields modified DNA damage response when the cells were subsequently exposed to ultra-violet radiation or menadione. Similarly, Sannino et al (2009) reported a significant reduction in cytogenetic damage in human blood lymphocytes which were pre-exposed to 900 MHz RF and then challenged with mitomycin C (a chemotherapeutic drug used to treat cancer patients).…”