Effects of simultaneous combined exposure to CDMA and WCDMA electromagnetic field on immune functions in rats

Despite the importance of the immune system in defending the body against infection and cancer, little research on the possible effects of radiofrequency electromagnetic field (RF-EMF) signals on immune functions exists, and, in the case of simultaneous combined exposure of RF-EMF, to the best of our knowledge no work has been done. The aim of this study was to assess the effect of simultaneous exposure to two types of RF-EMF signals, single code division multiple access (CDMA) and wideband code division multiple access (WCDMA) signals on the immune system of rats.

Male Sprague-Dawley rats were exposed to RF-EMF for 45 min/day, 5 days/week for up to 8 weeks. The whole body average specific absorption rate (SAR) of CDMA or WCDMA was 2.0 W/kg. Every 2 weeks after the experiment began, 20 rats were autopsied. Blood hematology, subtype population of splenocytes and cytokine production or mRNA expressions, interleukin (IL)-6, tumor necrosis factor (TNF)-α, IL-1β, interferon (IFN)-γ and transforming growth factor (TGF)-β from the splenocytes or IL-6, TNF-α, and immunoglobulin (Ig) of IgG and IgM from blood serum, were examined.

The results suggest that 8-week exposure to CDMA (849 MHz) and WCDMA (1.95 GHz) RF simultaneously at 2.0 W/kg each for 45-min RF-EMF exposure (total, 4 W/kg) did not affect these immune parameters.

The present experiments suggest that simultaneous combined exposure of CDMA and WCDMA with total SAR dose of 4.0 W/kg for 45 min/day for 8 weeks, which is a relatively high SAR level compared to the exposure levels for the human system recommended by International Commission on Non-Ionizing Radiation Protection (ICNIRP, 0.4W/kg for whole body exposure levels and 2.0 W/kg for local exposure levels of general public), did not have any detectable effects on immune function in rats.