Non-thermal Exposure to Radiofrequency Energy from Digital Wireless Phones does not Affect Ornithine Decarboxylase Activity in L929 Cells

Abstract

L929 murine fibroblast cells were exposed to radiofrequency (RF) radiation from a time division multiple access wireless phone operating at 835 MHz frequency to determine the effect of RF-radiation energy emitted by wireless phones on ornithine decarboxylase (ODC) activity in cultured cells. Exposure was for 8 h to an average specific absorption rate (SAR) from <1 W/kg up to 15 W/kg. After exposure, cells were harvested and ODC activity was measured. No statistically significant difference in ODC activity was found between RF-radiation-exposed and sham-exposed cells at non-thermal specific absorption rates. At SARs which resulted in measurable heating of the medium, a dose-dependent decrease in enzymatic activity was observed and was shown to be consistent with a comparable decrease caused by non-RF-radiation heating. Thus we observed only the well-known enzyme inhibition due to heating, rather than the previously reported enhancement attributed to RF-radiation exposure.

Ornithine decarboxylase activity of L929 cells after exposure to continuous wave or 50 Hz modulated radiofrequency radiation—a replication study

“…In their attempt to replicate results of Penafiel et al [1997], Desta et al [2003] reported results that were quite consistent with the present study. They exposed L929 cells in a Crawford chamber for 8 h to DAMPS modulated RF radiation at SAR levels from <1 to 15 W/kg and no enhancement of ODC activity was observed.…”

Exposure to Radiofrequency Radiation (900 MHz, GSM signal) does not Affect Micronucleus Frequency and Cell Proliferation in Human Peripheral Blood Lymphocytes: An Interlaboratory Study

“…Data are available from in vivo and in vitro studies for different cellular targets such as gene expression (4)(5)(6), intracellular Ca ϩϩ concentration (7,8), cell proliferation (9)(10)(11), enzyme activity (12)(13)(14)(15) and apoptosis (5,11,16).…”

Radiofrequency radiation does not significantly affect ornithine decarboxylase activity, proliferation, or caspase-3 activity of fibroblasts in different physiological conditions

“…Some reports have indicated increased ODC activity in cells exposed to a 835 MHz Digital advanced mobile phone system (DAMPS, 50 Hz modulated) signal (Litovitz et al 1993, whereas some studies were not able to confirm these results with or without DAMPS modulation (Desta et al 2003, Hö ytö et al 2007b), or with CW or GSM signal at 900 MHz (Hö ytö et al 2006 or at 872 MHz (Hö ytö et al 2007a). Desta et al (2003) reported decreased ODC activity after RF radiation exposure at SAR levels over 6 W/kg, but the temperature increase in cell cultures was shown to cause this effect, and this was further confirmed by our previous work (Hö ytö et al 2006). The results of the present study support the conclusion that ODC activity in L929 cells is not affected by RF radiation if temperature is kept constant.…”

“…Reports of RF radiation-induced alterations in cellular ODC activity were in the range of 40-90% in murine L929 fibroblasts, Reuber H35 hepatoma, Chinese hamster ovary, and 294T melanoma cells (Byus et al 1988, Litovitz et al 1993. Some recent studies were unable to show any effects of RF radiation on ODC activity in vitro (Desta et al 2003, Höytö et al 2006) and also a decrease in activity in rat primary astrocytes has been reported (Höytö et al 2007a).…”