The American Geophysical Union is meeting in Honolulu this week to discuss the impact of Japan's 2011 earthquake and tsumani, and the resulting nuclear plant disaster at Fukushima, and their talks are breeding a lot of terrifying headlines: the plant's radiation, it would appear, could hit the Pacific coast by April; some has already been detected offshore Canada.
It's enough to drown out the assurances of scientists that we have no reason to be worried. “It’s clearly not an environmental or human health radiological threat,” John Norton Smith, a senior research scientist at Canada’s Bedford Institute of Oceanography who detected minuscule amounts of cesium-134 off his country's coast, told KQED.
We've known that the radiative water spilled into the Pacific from Fukushima was headed this way for a while now; researchers are following it both in order to counter the glut of misinformation circulating, and also because of what it can teach them about the way in which ocean currents move throughout the ocean -- diluting the radiation in the process.
"The radioactivity is also being transported over very long distances with the ocean currents, but will at the same time be diluted to levels where there is no concern for harmful effects on sea life or for using, for example, the beaches along the North American west coast for recreational purposes," Carl-Magnus Larsson, chair of the UN's Scientific Committee on the Effects of Atomic Radiation, explained to Al Jazeera.
There's much, much more on the rumors and myths being circulated, and why they're mostly wrong, courtesy of Dr. Kim Martini, a physical oceanographer at the University of Alaska, Fairbanks, here.
The people with the most reason for concern, of course, are those living in the plant's immediate vicinity. Writing Tuesday in the journal Proceedings of the National Academy of Sciences, researchers at Kyoto University reported that there, too, radiation isn't posing a significant risk. By a year after the disaster, they found, people living on the outskirts of the evacuation zone were receiving only slightly more radiation than the normal amount we're zapped with every day.
Scientists explain it like this: there's no such thing as a "safe" level of radiation exposure. But if you're living here on Earth, there's also no such thing as avoiding radiation entirely. This new study looked at three towns that were only about 20 to 50 kilometers (12 to 30 miles) from the plant, hooking residents up to dosimeters to measure their radiation exposure and studying the food they ate, much of which was grown in personal vegetable gardens. They found that in 2012, residents were exposed to between .89 and 2.51 millisieverts of the radioactive element cesium. (A sievert is a measure of radiation that quantifies its ability to damage biological tissue -- more on that here). Compare that to the average amount of radiation that people in Japan are exposed to from natural sources: 2.09 millisieverts.
Compare that, too, to the amount of radiation those in the hardest-hit areas were exposed to immediately after the explosion, which the World Health Organization reported was between 12 and 25 millisieverts. Even that higher dosage, scientists were careful to point out, is only the equivalent of one or two CAT scans.
As for the more tangible concern -- cancer risk -- the researchers also reported encouraging findings. The average risk of cancer for any of the residents studied only increased by 1.06 percent. That's especially small when put into context: a typical person living in the U.S., for example, already has a roughly 40 percent chance of developing cancer in their lifetime. A 1 percent increase isn't nothing, but the researchers say it's unlikely to be noticeable on a epidemiological level. "The lifetime excess risk is small compared with the baseline risk of the Japanese population," they wrote. Their results echoed WHO's 2013 assertion that any increase in disease from the meltdown was "likely to remain below detectable levels."
The study confirms the Japanese government's assertions that decontamination efforts have been successful. On Sunday, officials announced that some of the 138,000 people who, three years later, remain evacuated from their homes nearby Fukushima will soon be allowed to return. About 300 people will be given the all-clear by April 1; over the next two years, 31,000 more could follow.
That the situation at Fukushima has been mismanaged from the start, however, is unlikely to help put remaining fears to rest. In its latest show of incompetence, Tepco, the plant's operator, admitted that it "significantly underestimated" radiation levels in water samples taken last year (the water wasn't from the ocean). It will be decades before the plant is entirely decommissioned, during which time there will be plenty of opportunity to set off new catastrophes. Rest assured, at least, that the world will be watching closely.