Timothy J. Jorgensen, Director of the Health Physics and Radiation Protection Graduate Program and Associate Professor of Radiation Medicine, Georgetown University - You might guess that a frequent flyer’s radiation dose is coming from the airport security checkpoints, with their whole-body scanners and baggage x-ray machines, but you’d be wrong. The radiation doses to passengers from these security procedures are trivial. The major source of radiation exposure from air travel comes from the flight itself. Most people do not fly 370,000 miles (equal to 150 flights from Los Angeles to New York) within their lifetimes. So for the average flyer, the increased risk is far less than 0.01 percent.
Jay Lehr, Ph.D. Science Director at The Heartland Institute: New research shows people exposed to low-doses of radiation, contrary to the assumptions behind the regulatory standards of U.S. agencies, are not at increased risk of developing cancer. Scientific and regulatory bodies currently estimate the risk of low doses by extrapolating directly (linearly) from the risk known to exist from high doses. They assume there is no threshold of exposure to radiation below which cancer might not be caused and that a low dose of radiation might have a protective effect called hormesis.
Edward Calabrese, Professor of Toxicology at the University of Massachusetts, Amherst: Considerable recent ﬁndings have revealed that the linear dose response for cancer risk assessment has not only outlived its utility in predicting risk but is based on a ﬂawed scientiﬁc foundation. The present article characterizes this demise of a key concept of environmental risk assessment, in the framework of a ﬁgurative obituary of a long-lived concept that has poorly served society. This obituary is intended to illustrate an integrated mix of poignant and improper historical judgments that led to both the acceptance and ultimately the demise of this once intellectually facile and nearly universally accepted concept.
Dr. A. David Rossin is a Center Affiliated Scholar, Center for International Security and Arms Control, Stanford University. He was President of the American Nuclear Society (1992-93) and served as Assistant Secretary for Nuclear Energy, USDOE, in 1986-87: He initiated this letter to the National Academy of Sciences recommending that guidelines for radiation risk assessment be based on science rather than the arbitrary Linear No Threshold Model.
Theodore (Ted) Rockwell, Member, National Academy of Engineering: We have the ability to measure very small amounts of radiation - we can actually detect single atoms as they disintegrate. So when we hear the clatter of a radiation detector, we feel that we are in danger. But the numbers we encounter from various human-made sources are quite trivial compared with the natural bath of radiation that the galaxies pour down on us as cosmic rays, and the earth and all its lovely vegetation produce, and even our water, food, and our bodies themselves are naturally radioactive.