Daniel Hirsch, Haakon Williams, Cameron Kuta
In May, President Donald Trump issued a series of executive orders that, in part, require the US Nuclear Regulatory Commission (NRC) to consider dramatically weakening its radiation protection standard. If federal radiation limits are gutted in the manner urged by the president, the new standard could allow four out of five people exposed over a 70-year lifetime to develop a cancer they would not otherwise get.
Contesting the scientific consensus. Section 5(b) of the executive order—formally titled “Ordering the Reform of the Nuclear Regulatory Commission”—directs the NRC to issue a proposed “wholesale revision of its regulations and guidance documents,” including reconsideration of the agency’s “reliance on the linear no-threshold (LNT) model for radiation exposure.” The LNT model maintains that risk from radiation exposure is proportional to the dose: Even a tiny amount of radiation causes some small but real increased risk of cancer, and that risk goes up linearly as the dose increases.
While most Americans have doubtless never heard of the LNT model, it has been the bedrock of radiation exposure risk analysis for decades and forms the basis of public health protection from radiation. The LNT model is scientifically robust, supported by the longstanding and repeatedly affirmed determinations on low-dose radiation by the National Academies of Sciences, Engineering, and Medicine, virtually all international scientific bodies, the Environmental Protection Agency (EPA), and the NRC itself.
Despite the LNT model’s long track record and the well-established body of scientific evidence upon which it is built, President Trump has unilaterally issued a presidential finding that this scientific consensus is wrong. His order could lead to LNT’s complete abandonment in a matter of months, posing a serious increase in the amount of radiation that industries and government agencies would be allowed to inflict upon the public.
If the NRC goes along with Trump’s assertion, the weakening of radiation protection standards would likely be extreme. Advocates of abandoning LNT have often asserted that low-dose radiation is harmless or even beneficial, and therefore, that the public health radiation limits should be hugely increased. In 2015, three petitions for rulemaking to the NRC proposed doing away with the LNT model and increasing allowable radiation exposures for everyone—including children and pregnant women—to 10 rem. (The Roentgen equivalent man (rem) is a unit of effective absorbed radiation in human tissue, equivalent to one roentgen of X-rays. One rem is equal to 0.01 Sievert in the international system of units.)
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