EMF Health-effects Research

Measurement of DNA damage in mammalian cells exposed in vitro to radiofrequency fields at sars of 3-5 w/kg.

Li L, Bisht KS, LaGroye I, Zhang P, Straube WL, Moros EG, Roti Roti JL.

Radiat Res 156:328-332, 2001

In the present study, we determined whether exposure of mammalian cells to 3.2-5.1 W/kg specific absorption rate (SAR) radiofrequency fields could induce DNA damage in murine C3H 10T(1/2) fibroblasts. Cell cultures were exposed to 847.74 MHz code-division multiple access (CDMA) and 835.62 frequency-division multiple access (FDMA) modulated radiations in radial transmission line (RTL) irradiators in which the temperature was regulated to 37.0 +/- 0.3 degrees C.

Using the alkaline comet assay to measure DNA damage, we found no statistically significant differences in either comet moment or comet length between sham-exposed cells and those exposed for 2, 4 or 24 h to CDMA or FDMA radiations in either exponentially growing or plateau-phase cells. Further, a 4-h incubation after the 2-h exposure resulted in no significant changes in comet moment or comet length.

Our results show that exposure of cultured C3H 10T(1/2) cells at 37 degrees C CDMA or FDMA at SAR values of up to 5.1 W/kg did not induce measurable DNA damage.

Additional Web Notes

The detection sensitivity being claimed in this paper is 0.3 rad (cG) with x-rays. They are using the Olive comet-assay method, and they now claim to have nearly doubled the senstitivity over their previous report (0.5 cG) in the Malyapa sensitivity study published in Radiation Research in 1999.

There was more that slight cynicism expressed at the time about this group's previous claims to such high sensitivities, including those expressed by Dr Peggy Olive herself. See

Dr Neil Cherry writes"

"I have been through the Motorola funded paper of Malyapa et al which claim to show no DNA damage from 2450 MHz and cell phone radiation. In fact there data does show significant DNA damage followed by repair, in a time sequence of length of exposure. Look closely at the DNA sequence in this latest paper and it shows a jump in DNA damage followed by induced repair, confirming Phillips. and Malyapa.

Please e-mail comments, information and updates to DON MAISCH: