Radiation that drifted across the Pacific from the meltdown at the Fukushima Daiichi reactors -- the nuclear disaster triggered when a devastating tsunami disabled the Japanese power plant in 2011 -- could ultimately cause up to 12 deaths and up to 30 cancers in Alaska and other U.S. states, according to a new calculation of global health impacts from the fallout.
These estimates appear to be a tiny fraction of the potential global toll (and include the possibility of zero deaths or cancers in North America). But they contradict some early predictions that there would likely be no health consequences for people in Alaska or other U.S. states -- and minimal problems, even in Japan.
"There are groups of people who have said there would be no effects," said civil engineering Professor Mark Z. Jacobson, one of the co-authors of the study in a story released by Stanford University.
"A month after the disaster," the authors added in the story, "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."
Up to 1,300 deaths
But in a long-term project at Stanford's Atmosphere / Energy Program in Civil and Environmental Engineering, Jacobson and PhD graduate John Ten Hoeve used sophisticated atmospheric models and detailed observations of actual fallout to gauge the very real impact by exposure to radioactive iodine-131, cesium-137, and cesium-134, and other substances. They also extrapolated exposure due to eating contaminated food and drinking contaminated water.
The results? The two scientists found that between 15 and 1,300 people may die from cancer as a direct result of exposure, inhalation and ingestion of radioactive particles from Fukushima Daiichi, with 24 to 2,500 total cases of cancer occurring across the globe. The vast majority of the deaths and illnesses will occur in Japan among residents living close to the plant, but a very small number of fatalities or illnesses could appear in Asian and North American communities.
"This study provides first estimates of the worldwide health impacts of the Fukushima nuclear accident," the authors wrote in the paper. "Because of the significant number of current nuclear power plants and their potential increase in the future, quantification of the health impacts from Fukushima is important."
An estimated 600 people died from non-radiological reasons due to the meltdown, including fatalities that occurred as a result of mandatory evacuations, the authors said.
The results of their analysis -- "Worldwide health effects of the Fukushima Daiichi nuclear accident" -- was published Tuesday in the journal Energy and Environmental Science. They said it was most detailed analysis of the health impact by the world's worst nuclear disaster since Chernobyl. The paper contains some disconcerting graphics showing how measurable (if relatively small) radioactive fallout moved across the Pacific and drifted over Alaska and other North American locales.
"The estimates have large uncertainty ranges," the authors explained, "but contrast with previous claims that the radioactive release would likely cause no severe health effects."
Tsunami of trash
The Stanford study adds to the growing list of unintended and far-reaching consequences from the T?hoku 9.0 megathrust earthquake of March 11, 2011. The temblor -- the fourth most powerful on record -- triggered what may be the most damaging tsunamis to ever strike a populated area. Some of the waves rose as high as 133 feet as they flushed up to six miles inland -- destroying or damaging 125,000 houses and buildings in 28 towns. More than 15,800 people died.
Since then, a tsunami of trash bobbed across the Pacific Ocean and has begun making landfall on the U.S. West Coast, British Columbia and Alaska. During the tsunami in Japan, a 45-foot wave inundated the area surrounding a nuclear power plant designed to withstand an 18-footer. Although the reactors were off-line when struck, the wave disabled the emergency generators that operated water pumps keeping fuel rods cool, ultimately leading to partial meltdowns, explosions and releases of radioactive material.
In their study of health impacts from the disaster, Ten Hoeve and Jacobson deployed a 3-D global atmospheric model developed over 20 years of research to predict where and how the radioactive material would be transported.
"Because of inherent uncertainties in the emissions and the health-effects model, the researchers found a range of possible death tolls, with a best estimate of 130," the authors explained. "Those affected according to the model were overwhelmingly in Japan, with extremely small effects noticeable in mainland Asia and North America."
Best estimate for total cancers across the globe was about 180, also with a very wide possible range.
"These worldwide values are relatively low," said Ten Hoeve in the story posted by Stanford. But he added that they should "serve to manage the fear in other countries that the disaster had an extensive global reach."
Still, as of 2011, the authors wrote, modest to major radioactive releases have occurred at six of the world's 441 nuclear power plants, or about 1.5 percent.
Beware California
That suggests "the risk of a meltdown is not small," they wrote. "This study finds that atmospheric and ground-level radioactivity from a meltdown, even when diluted to the large scale, may have quantifiable health impacts" around the globe.
The two scientists then applied what they learned to a hypothetical disaster in California. What if an identical meltdown occurred at the Diablo Canyon Power Plant, near San Luis Obispo, Calif.?
Although California's population density is one-fourth of Japan's, a Diablo Canyon disaster would cause 25 percent greater health effects. Why? A larger percentage of any Diablo Canyon fallout would drift over land instead of ocean, including real estate where tens of millions of people make their homes in San Diego and Los Angeles areas.
"There's a lot more to the issue than what we examined, which were the cancer-related health effects," Jacobson said in the Stanford story. "Fukushima was just such a large disaster in terms of soil and water contamination, displacement of lives, confidence in government oversight, cost and anguish."
Contact Doug O'Harra at doug(at)alaskadispatch.com