SAB NewsRadiation: Menace or Good Thing?Posted 11/2/2004 Until relatively recently, the scientific community believed that low doses of ionizing radiation caused detrimental health effects in proportion to the effects produced by high-level radiation. Much of this belief was founded on research conducted after the atomic bomb explosions in Hiroshima and Nagasaki. Studies concerning life span of atomic bomb survivors showed a linear relationship between cancer mortality and high doses of radiation. Consequently, the United Nations Scientific Committee on the Effects of Atomic Radiation proposed the linear no-threshold (LNT) theory. According to LNT theory: The effects of low doses of ionizing radiation can be estimated by linear extrapolation from effects observed by high doses. There is not any safe dose because even very low doses of ionizing radiation produce some biological effect. However, more and more evidence has accumulated that low-dose ionizing radiation is not only undamaging but often is beneficial. Despite this mounting body of data, a definitive explanation of this phenomenon remains elusive. Members of The Science Advisory Board weighed in on this discussion. Of the nearly 1,200 participants, 42% claim that the stimulation of immune system is responsible for low-dose ionizing radiation’s positive health effects. Almost equal percentages supported enhanced DNA repair (30%) versus free radical detoxification (28%) as the biological mechanism to best explain this phenomenon. “It certainly sounds radical to claim that low-level ionizing radiation may be an essential trace energy for life,” observes Tamara Zemlo, Ph.D., M.P.H, Director of Scientific & Medical Communications for The Science Advisory Board, “But studies have shown that it stimulates certain biologic functions.” Hence, the results of many investigations do not support the LNT theory calling into question whether it should abandoned for estimating low-dose radiation risks. To read more about this debate, please see Dr. Yuan’s Perspective, Chronic Radiation Is Beneficial to Human Beings. |
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