Another note about cell phones: While they’re not causing significant interference with medical equipment, it’s more comforting to believe they’re not frying your brain, either. This report from scientists at Wash U suggests we can speak, stress-free:
“We performed highly sensitive, extremely well-controlled tests on living cells irradiated with energy like that from mobile phones, but at levels 5 to 10 times higher than those set for the devices by regulatory agencies,” says Andrei Laszlo, Ph.D., associate professor of radiation oncology and a researcher at the Siteman Cancer Center at Barnes-Jewish Hospital and Washington University School of Medicine. “We see no indication that factors involved in the stress response increase their activity as a result of such exposures.”
Prior research into the effect of cell phones on the stress response has been fraught with contradictory results, which in part may be due to less-than-ideal experimental conditions. For example, in the past it has been difficult to prevent temperature changes caused by microwave exposure.
Because heating of tissues has been shown unlikely to be a component of the effect of cell phone radiation on biological systems, Laszlo and his group sought to reduce as far as possible any heating of the cells in culture during the study. Using sensitive equipment that continuously monitored and adjusted temperature, they were able to keep temperature variations to plus or minus 0.3 degrees centigrade.
Experiments like this are no substitute for large-scale prospective studies on cell phone-using populations (where will they find a control group of non-cell users?) Still, it’s nice to know that mobile phones aren’t causing harm to cells in vitro.
More: Recent articles in Radiation Research: this stress-factor article, and a piece on oncogene expression after irradiation. Drs. Laszlo’s and Roti Roti’s work was supported by Motorola.
