To conduct a large-scale in vitro study focused on the effects of low level radiofrequency fields from mobile radio base stations employing the International Mobile Telecommunications-2000 (IMT-2000) cellular system in order to test the hypothesis that modulated radiofrequency fields may act as a DNA damaging agent.
First, the responses of human cells to microwave exposure at a specific absorption rate (SAR) of 80 mW/kg, which corresponds to the limit of the average whole body SAR for general public exposure defined as a basic restriction in the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines were evaluated.
Second, it was investigated whether continuous wave and Wideband Code Division Multiple Access (W-CDMA) modulated signal radiofrequency fields at 2.1425 GHz induced different levels of DNA damage.
|Chamber||A beam-formed RF exposure incubator employing a horn antenna, a dielectric lens, and a culture case in an anechoic chamber was developed. For details, see the reference article. Briefly, two identical RF field exposure incubators, one for RF field exposure and the other for sham exposure, were established in separate anechoic chambers, and a mechanical switch in a dummy box allows the selection of RF field exposure or sham exposure.|
|Setup||This system allows simultaneous exposure of 49 (7 x 7 array) 35 mm culture dishes with a uniform SAR distribution in the medium of all 49 culture dishes. Five dishes in the inner dish positions were used in this study. They were subjected to RF field or sham exposure for 2 or 24 h, respectively.|
Under the same radiofrequency field exposure conditions, no significant differences in the DNA strand breaks were found between the test groups exposed to W-CDMA or continuous wave irradiation and the sham exposed negative controls. The data confirm that low level exposures do not act as a genotoxicant up to a SAR of 800 mW/kg.