The report by the United Nations Scientific Committee on the Effects of Atomic Radiation on the radiation impacts of the 2011 Fukushima Daiichi accident came out a few weeks ago. A lot of it is a dense, heavy read, but the introduction – essentially the executive summary - is much easier going.
I wasn’t sure what to expect of the report, except that it was unlikely to be alarming or disturbing. The Japanese did a good job of keeping people out of harm’s way – more harm’s way, actually, as the earthquake and tsunami that precipitated the nuclear accident killed over 20,000 people - and the report more-or-less confirms that, if largely by implication.
The best section to see this is Health Effects, starting on page 17.
The doses to the general public, both those incurred during the first year and estimated for their lifetimes, are generally low or very low. No discernible increased incidence of radiation-related health effects are expected among exposed members of the public or their descendants.
This next bit is interesting: it essentially explains why non-Japanese commentary on reopening the facilities can seem glib:
The most important health effect is on mental and social well-being, related to the enormous impact of the earthquake, tsunami and nuclear accident, and the fear and stigma related to the perceived risk of exposure to ionizing radiation.
It is a stigma and not rational, but that’s how it is. Nuclear energy got entangled in – and contributed to – a nationally traumatic event. It may not have been the most traumatizing aspect, but given the circumstances, it was plenty enough. One has to give Japan room to weigh in factors that we can barely imagine – what it decides to do is up to the government and the people, whatever we may think of it.
Still, given the hysteria expressed over here, the actual impact on health has been exceptionally small:
For adults in Fukushima Prefecture, the Committee estimates average lifetime effective doses to be of the order of 10 mSv or less, and first-year doses to be one third to one half of that. While risk models by inference suggest increased cancer risk, cancers induced by radiation are indistinguishable at present from other cancers. Thus, a discernible increase in cancer incidence in this population that could be attributed to radiation exposure from the accident is not expected.
All children in Fukushima Prefecture were scanned for evidence of thyroid abnormalities due to exposure to radioactive iodine. This can lead to thyroid cancer later on.
Increased rates of detection of nodules, cysts and cancers have been observed during the first round of screening; however, these are to be expected in view of the high detection efficiency.
I wasn’t sure what that meant, but the next sentence clarifies it.
Data from similar screening protocols in areas not affected by the accident imply that the apparent increased rates of detection among children in Fukushima Prefecture are unrelated to radiation exposure.
And if you’ve seen Chernobyl Diaries, this will act as the tonic:
There have been many studies of possible heritable effects following radiation exposure; such studies were reviewed by the Committee in 2001. It has been generally concluded that no heritable effects in humans due to radiation exposure have been explicitly identified (specifically in studies of offspring of survivors of the atomic bombings).
James Conca over at Forbes has much the same response as we do to the report:
But if you want to continue feeling afraid, and want to make sure others keep being afraid, by all means ignore this report on Fukushima. But then you really can’t keep quoting previous UNSCEAR policy and application of LNT (the Linear No-Threshold dose hypothesis) to support more fear.
Conca spends a few paragraphs on LNT (which basically says that all levels of radiation carry health risks), which Conca and many others consider unsupported by evidence. He also summarizes findings I missed:
All of the foods produced within Fukushima Prefecture show radioactivity a hundred times less than the low limits set by the Japanese government after the accident, and a thousand times lower than limits in the United States.
I found Conca’s conclusion about relative risk especially germane:
During the writing of this post, five people were killed, a hundred injured and an entire building destroyed in a natural gas explosion in Florida (Gas Explosion In Jail), continuing the trend of a gas explosion a week in America. In addition, a crude-oil-carrying train derailed and burst into flames in downtown Lynchburg (Virginia Crude Train Explodes), spilling thousands of gallons of oil and catching the James River on fire. No one was killed, but the crash was the sixth fiery derailment to occur in North America since a runaway train in Quebec derailed and exploded, killing 47 people last July and destroying a major portion of the town.
These kinds of stories – and Fukushima Daiichi, too - are catnip to renewable energy advocates, so it can be a double edged turbine blade. Playing the “you’re more likely to die driving a car” game only gets you so far – almost every human activity carries risk. The point is, nuclear energy is exceptionally low on the risk thermometer, which the UNSCEAR report makes abundantly clear.