Revisiting low-level radiation

A recent convention in Pasco brought together participants from all over the world, representing multiple scientific, medical and regulatory disciplines, and people directly impacted by evacuations caused by radiation concerns. The topic was the effects of low levels of radiation on humans.

This has been argued with considerable heat in the media for decades. At issue was whether the most current research and studies should influence existing regulations for the protection of nuclear workers and the public.

Presentations detailed the most current findings and conclusions. Attendees could be categorized into three groups:

1. Those who believe that the Linear No Threshold (LNT) model should continue to be used to set radiation protection guidelines.

2. Those who believe there is a threshold below which there are no negative health effects.

3. Those who believe that there is a beneficial effect to very low doses (the Hormesis effect). The second and third groups have mountains of current and recent research to substantiate their positions.

What is most compelling is the areas of agreement among the three camps.

A questionnaire was sent to the attendees after the conference. The results were as instructive as the information from the conference itself.

Over 94 percent of respondents agreed that: “In general, the public’s perception of the risk of low doses of radiation is far greater than the observed risk based on current scientific knowledge” — a virtual consensus. Given the range of disciplines represented at the conference, that is an astounding number.

A principal ethical and moral consideration in this debate is the unintended consequences of ultra-conservative regulations, such as stress-related deaths due to the evacuations at Fukushima, and earlier, reported abortions in the aftermath of Chernobyl.

When asked to respond to a statement in this regard, over 88 percent of respondents agreed or strongly agreed that the LNT model has resulted in such unintended consequences.

Perhaps the most telling survey question of all was: “In the event of a radiological release, what level of projected dose would you tolerate for yourself and/or family members before considering evacuation…?” Three-quarters of the world’s greatest experts in a broad variety of radiation-related disciplines would not consider evacuating their families until the threat level reached at least 50 mSv, or 5 rem. For comparison, the average background radiation in the United States, not counting medical diagnostics and treatments, averages about 300 mrem (3 mSv) per year.

There are areas around the world which experience much higher levels of everyday background radiation than the United States. If the LNT premise were true, there should be a proportionate increased rate of radiogenic health issues in these areas, but there isn’t.

Research continues to add to our immense amount of knowledge. Indeed, the effects of ionizing radiation on humans is one of the most thoroughly studied phenomena in all of science.

The real health effects from low doses of radiation are vanishingly small or nonexistent compared to the problems generated by fear and misunderstanding of radiation effects, especially after a nuclear accident like Chernobyl or Fukushima.

The moral and ethical resolution of this issue in the direction of greater common sense has tremendous implications for Hanford cleanup, for the management of nuclear accidents, and for the American taxpayer in the form of reduced expenditures for nonexistent problems.