from Japan’s Fukushima Daiichi nuclear disaster may eventually cause
approximately 130 deaths and 180 cases of cancer, mostly in Japan, Stanford University
researchers have calculated.
estimates have large uncertainty ranges, but contrast with previous claims that
the radioactive release would likely cause no severe health effects.
numbers are in addition to the roughly 600 deaths caused by the evacuation of
the area surrounding the nuclear plant directly after the March 2011
earthquake, tsunami, and meltdown.
PhD graduate John Ten Hoeve and Stanford civil engineering Professor Mark
Z. Jacobson, a senior fellow at the Precourt Institute for Energy and the
Woods Institute for the Environment, are set to publish their findings in the
journal Energy and Environmental
Science. The research constitutes the first detailed analysis of the
event’s global health effects.
The Fukushima Daiichi meltdown was the most extensive nuclear disaster since
Chernobyl. Radiation release critically contaminated a “dead zone” of
several hundred square kilometers around the plant, and low levels of
radioactive material were found as far as North America and Europe.
most of the radioactivity was dumped in the Pacific—only 19% of the released
material was deposited over land—keeping the exposed population relatively
are groups of people who have said there would be no effects,” said
after the disaster, the head of the United Nations Science Committee on the
Effects of Atomic Radiation, for example, predicted that there would be no
serious public health consequences resulting from the radiation.
Evaluating the claim, Ten Hoeve and Jacobson used a 3D global atmospheric
model, developed over 20 years of research, to predict the transport of
radioactive material. A standard health-effects model was used to estimate
human exposure to radioactivity.
of inherent uncertainties in the emissions and the health-effects model, the
researchers found a range of possible death tolls, from 15 to 1,300, with a
best estimate of 130. A wide span of cancer morbidities was also predicted,
anywhere from 24 to 2,500, with a best estimate of 180.
affected according to the model were overwhelmingly in Japan, with extremely
small effects noticeable in mainland Asia and North America. The United States
was predicted to suffer between 0 and 12 deaths and 0 and 30 cancer
morbidities, although the methods used were less precise for areas that saw
only low radionuclide concentrations.
worldwide values are relatively low,” said Ten Hoeve. He explained they
should “serve to manage the fear in other countries that the disaster had
an extensive global reach.”
The Japanese government’s response was much more rapid and coordinated than
that of the Soviets in Chernobyl, which may have mitigated some of the cancer
government agencies, for example, evacuated a 20-km radius around the plant,
distributed iodine tablets to prevent radioiodine uptake, and prohibited
cultivation of crops above a radiation threshold—steps that Ten Hoeve said
“people have applauded.”
paper also notes that nearly 600 deaths were reported as a result of the
evacuation process itself, mostly due to fatigue and exposure among the elderly
and chronically ill. According to the model, the evacuation prevented at most
245 radiation-related deaths—meaning the evacuation process may have cost more
lives than it saved.
the researchers cautioned against drawing conclusions about evacuation policy.
still have an obligation to evacuate people according to the worst-case scenario,”
To test the effects of varying weather patterns and geography on the reach of a
nuclear incident, the two researchers also analyzed a hypothetical scenario: an
identical meltdown at the Diablo Canyon Power Plant, near San Luis Obispo,
California’s population density being about one-fourth that of Japan’s, the
researchers found the magnitude of the projected health effects to be about 25%
model showed that rather than being whisked toward the ocean, as with
Fukushima, a larger percentage of the Diablo Canyon radioactivity deposited
over land, including population centers such as San Diego and Los Angeles.
stressed, however, that none of the calculations expressed the full scope of a
a lot more to the issue than what we examined, which were the cancer-related
health effects,” he said. “Fukushima was just such a large disaster
in terms of soil and water contamination, displacement of lives, confidence in
government oversight, cost and anguish.”
Source: Stanford University