Abstract
The potential health effects of radio frequency (RF) radiation associated with cellular mobile telephones and related wireless devices remain a focus of concern. Although our knowledge regarding the health effects of RF radiation has increased considerably, the scientific evidence on biological effects of RF radiation associated with these wireless devices is still tentative. The uncertainties persist, in part, because of the limited number and scope of studies that have been conducted. Aside from the lack of a scientific consensus on experimental studies that provide clear evidence either refuting or supporting the cancer induction or promotion potential of RF radiation from cell phones, there is a concern that an established effect from wireless radiation, however small, could have a considerable impact in terms of public health. This chapter provides an updated review on recent research results on cancer induction and promotion in normal and transgenic mice and rats subjected to prolonged or life-long exposure to modulation schemes such as GSM, TDMA, CDMA, UMTS, and others. A majority of the laboratory mouse and rat studies did not exhibit a significant difference in carcinogenic incidences between exposed and sham-exposed animals. Although this observation may be comforting from the perspective of safety evaluation, most of the studies are one-of-a-kind investigations – only three mouse and perhaps four rat studies were designed as replication or confirmation studies. It is noteworthy that the findings of these studies have not been consistent, making it difficult to arrive at a definitive conclusion. It could be a major flaw that in a majority of the investigations, cage-control animals were not part of the investigation or were not included in the data analyses. Moreover, restraining the experimental animals during exposure could have introduced a stress factor, which further complicates interpretation of the results since stress has often been associated with cancer induction in these animals.