Robert Hargraves is right to reject the theory that “any level of radiation is harmful” (“How Much Radiation Is Too Much?” op-ed, Sept. 22). This theory, proposed in 1946, before DNA was discovered, is a grave impairment to accurate public perception of radiation risks and the use of nuclear energy. Unfortunately, it has been the dominant belief of the Atomic Energy Commission and now the Nuclear Regulatory Commission, although there was scant evidence of its truth in 1946 and even less now.
We now understand how radiation can damage our DNA, which is also damaged constantly due to exposure to sunlight and natural and artificial carcinogens in our food and air. We also know that our cells have no less than five molecular pathways that are active to repair DNA and prevent the development of cancer. Thus, low-level molecular damage from radiation or carcinogens is routinely repaired by our body, rendering these exposures harmless.