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Harm from Fukushima Radiation: A Matter Of Perspective
A New York sushi chef tests fish for radiation. Image by Getty Images via @daylife
A leading biophysicist has cast a critical light on the government’s reassurances that Americans were never at risk from Fukushima fallout, saying “we really don’t know for sure.”
When radioactive fallout from Japan’s nuclear disaster began appearing in the United States this spring, the Obama Administration’s open-data policy obligated the government to inform the public, in some detail, what was landing here.
Covering the story, I watched the government pursue what appeared to be two strategies to minimize public alarm:
- It framed the data with reassurances like this oft-repeated sentence from the EPA: “The level detected is far below a level of public health concern.” The question, of course, is whose concern.
- The EPA seemed to be timing its data releases to avoid media coverage. It released its most alarming data set late on a Friday—data that showed radioactive fallout in the drinking water of more than a dozen U.S. cities.
Friday and Saturday data releases were most frequent when radiation levels were highest. And despite the ravages newspapers have suffered from internet competition, newspaper editors still have not learned to assign reporters to watch the government on weekends.
As a result, bloggers broke the fallout news, while newspapers relegated themselves to local followups, most of which did little more than quote public health officials who were pursuing strategy #1.
For example, when radioactive cesium-137 was found in milk in Hilo, Hawaii, Lynn Nakasone, administrator of the Health Department’s Environmental Health Services Division, told the Honolulu Star-Advertiser: ”There’s no question the milk is safe.”
Nakasone had little alternative but to say that. She wasn’t about to dump thousands of gallons of milk that represented the livelihood of local dairymen, and she wasn’t authorized to dump the milk as long as the radiation detected remained below FDA’s Derived Intervention Level, a metric I’ll discuss more below.
That kind of statement failed to reassure the public in part because of the issue of informed consent—Americans never consented to swallowingany radiation from Fukushima—and in part because the statement is obviously false.
There is a question whether the milk was safe.
In spite of the relative level of Fukushima radiation, which many minimized through comparison to radiation from x-rays and airplane flights—medical experts agree that any increased exposure to radiation increases risk of cancer, and so, no increase in radiation is unquestionably safe.
Whether you choose to see the Fukushima fallout as safe depends on the perspective you adopt, as David J. Brenner, a professor of radiation biophysics and the director of the Center for Radiological Research at Columbia University Medical Center, elucidated recently in The Bulletin of The Atomic Scientists:
Should this worry us? We know that the extra individual cancer risks from this long-term exposure will be very small indeed. Most of us have about a 40 percent chance of getting cancer at some point in our lives, and the radiation dose from the extra radioactive cesium in the food supply will not significantly increase our individual cancer risks.
But there’s another way we can and should think about the risk: not from the perspective of individuals, but from the perspective of the entire population. A tiny extra risk to a few people is one thing. But here we have a potential tiny extra risk to millions or even billions of people. Think of buying a lottery ticket — just like the millions of other people who buy a ticket, your chances of winning are miniscule. Yet among these millions of lottery players, a few people will certainly win; we just can’t predict who they will be. Likewise, will there be some extra cancers among the very large numbers of people exposed to extremely small radiation risks? It’s likely, but we really don’t know for sure.
via Fukushima: What don’t we know? | Bulletin of the Atomic Scientists.
A few people certainly will “win,” which is why it’s so interesting that the EPA’s standard for radionuclides in drinking water is so much more conservative than the FDA’s standard for radionuclides in food.
The two agencies anticipate different endurances of exposure—long-term in the EPA’s view, short-term in FDA’s. But faced with the commercial implications of its actions, FDA tolerates a higher level of mortality than EPA does.
FDA has a technical quibble with that last sentence. FDA spokesman Siobhan Delancey says:
Risk coefficients (one in a million, two in ten thousand) are statistically based population estimates of risk. As such they cannot be used to predict individual risk and there is likely to be variation around those numbers. Thus we cannot say precisely that “one in a million people will die of cancer from drinking water at the EPA MCL” or that “two in ten thousand people will die of cancer from consuming food at the level of an FDA DIL.” These are estimates only and apply to populations as a whole.
The government, while assuring us of safety, comforts itself in the abstraction of the population-wide view, but from Dr. Brenner’s perspective, the population-wide view is a lottery and someone’s number may come up.
Let that person decide whether we should be alarmed.
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