Single Code Division Multiple Access Research Articles

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

Purpose: 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.Materials and methods: 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.Results: 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.Conclusions: 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.

The effects of simultaneous combined exposure to CDMA and WCDMA electromagnetic fields on rat testicular function

Wireless mobile phones and other telecommunication devices are used extensively in daily life. We therefore examined the effects of combined exposure to radiofrequency electromagnetic fields (RF-EMF) on rat testicular function, specifically with respect to sensitive processes such as spermatogenesis. Male rats were exposed to single code division multiple access (CDMA) and wideband code division multiple access (WCDMA) RF signals for 12 weeks. The RF exposure schedule comprised 45 min/day, 5 days/week for a total of 12 weeks. The whole-body average specific absorption rate (SAR) of CDMA and WCDMA was 2.0 W/kg each or 4.0 W/kg in total. We then investigated the correlates of testicular function such as sperm count in the cauda epididymis, testosterone concentration in the blood serum, malondialdehyde concentrations in the testes and epididymis, frequency of spermatogenesis stages, and appearance of apoptotic cells in the testes. We also immunoblotted for p53, bcl2, GADD45, cyclin G, and HSP70 in the testes of sham- and combined RF-exposed animals. Based on the results, we concluded that simultaneous exposure to CDMA and WCDMA RF-EMFs at 4.0 W/kg SAR did not have any observable adverse effects on rat spermatogenesis.

Lymphoma development of simultaneously combined exposure to two radiofrequency signals in AKR/J mice

There are public concerns regarding possible carcinogenic or cancer-promoting effects of radiofrequency electromagnetic fields (RF-EMFs) because of the extensive use of wireless mobile phones and other telecommunication devices in daily life. However, so far it is unclear if non-thermal exposure of single EMF exposure in animal studies has a direct influence on carcinogenesis. Here, carcinogenic effects of combined signal RF-EMFs on AKR/J mice, which were used for the lymphoma animal model, were investigated. Six-week-old AKR/J mice were simultaneously exposed to two types of RF signals: single code division multiple access (CDMA) and wideband code division multiple access (WCDMA). AKR/J mice were exposed to combined RF-EMFs for 45 min/day, 5 days/week, for a total of 42 weeks. The whole-body average specific absorption rate (SAR) of CDMA and WCDMA fields was 2.0 W/kg each, 4.0 W/kg in total. When we examined final survival, lymphoma incidence, and splenomegaly incidence, no differences were found between sham- and RF-exposed mice. However, occurrence of metastasis infiltration to the brain in lymphoma-bearing mice was significantly different in RF-exposed mice when compared to sham-exposed mice, even though no consistent correlation (increase or decrease) was observed between male and female mice. However, infiltration occurrence to liver, lung, and spleen was not different between the groups. From the results, we suggested that simultaneous exposure to CDMA and WCDMA RF-EMFs did not affect lymphoma development in AKR/J mice.

Lack of Teratogenicity after Combined Exposure of Pregnant Mice to CDMA and WCDMA Radiofrequency Electromagnetic Fields

Concern about the possible adverse effects of radiofrequency (RF)-field exposure on public health has increased because of the extensive use of wireless mobile phones and other telecommunication devices in daily life. The murine fetus is a very sensitive indicator of the effects of stress or stimuli in the environment. Therefore, we investigated the teratogenic effects of multi-signal radiofrequency electromagnetic fields (RF EMFs) on mouse fetuses. Pregnant mice were simultaneously exposed to two types of RF signals, single code division multiple access (CDMA) and wideband code division multiple access (WCDMA). Mice received two 45-min RF-field exposures, separated by a 15-min interval, daily throughout the entire gestation period. The whole-body average specific absorption rate (SAR) of CDMA or WCDMA was 2.0 W/kg. The animals were killed humanely on the 18th day of gestation and fetuses were examined for mortality, growth retardation, changes in head size and other morphological abnormalities. From the results, we report for the first time that simultaneous experimental exposure to CDMA and WCDMA RF EMFs did not cause any observable adverse effects on mouse fetuses.