Nearly a year after the Japanese tsunami and subsequent meltdown at the Fukushima nuclear plant, the good news is that the risk from radiation doesn’t seem to be as high as many initially feared. Take the Pacific Ocean, for example, where most of the radioactive fallout from the plant eventually ended up. Nicholas Fisher, a marine science professor at New York’s Stony Brook University, took samples of the seawater three months after the accident. He found levels of radiation that were elevated, but still just a fraction of the amount of radioactivity sea life is exposed to from naturally occurring potassium in seawater.
As Fisher told CNN in an interview:
The total radiation in the marine organisms that we collected from Fukushima is still less than the natural radiation background that the animals already had, and quite a bit less. It’s about 20%.
MORE: Aftermath: How Japan Will Recover From the Quake
So that’s good news for the Pacific Ocean—and those of us who might want to take fish from it. Early reports also suggest that the radiation risk in the area surrounding Fukushima may be less severe as well, though scientists will need more time to be certain.
But what about the U.S.? Thousands of Americans bought potassium iodine pills in the wake of the Fukushima meltdown, afraid that a radioactive cloud was on it was to the U.S. Did any Fukushima fallout make it over here—and if so, was it enough to cause any harm?
It turns out that you can rest easy. In a new study, researchers from the U.S. Geological Survey found that only minute levels of radiation from Fukushima reached the U.S. in the immediate aftermath of the accident. As part of the National Atmospheric Deposition Program (NADP), USGS scientists looked for radiation at 167 sites around the country a few weeks after Fukushima. Just about 20% showed levels of radiation from the plant—and those levels were minimal at most, well below any threat to human health.
From USGS director Marcia McNutt:
Japan’s unfortunate nuclear nightmare provides a rare opportunity for U.S. scientists to test an infrequently needed national capability for detecting and monitoring nuclear fallout over a wide network. Had this been a national incident, NADP would have revealed the spatial and temporal patterns of radioactive contamination in order to help protect people and the environment.
VIDEO: After the Tsunami
The greatest concentration of radiation was found on the West Coast, which makes sense. Radioactive particles can be carried in the high atmosphere for thousands of miles, but when they meet a rain system, they can fall to the Earth as precipitation, spreading the radiation—hence the term “fallout.” Some fallout from Fukushima was found as far away as the East Coast and Europe in the month after the accident, but the levels were so low that researches likely wouldn’t have detected the radiation without looking. The positive, as McNutt put it, is that the accident gave the USGS a chance to work with its radioactive detection network, which could come in handy if another accident occurs—especially one in the U.S.
Which of course brings us to the big question from Fukushima: could it happen here? That remains unanswered, but anyone interested in the issue should read a new article in Prevention by the journalist Chanan Tigay. Tigay spent months reporting inside the Diablo Canyon nuclear power plant in California, which sits near four earthquake faults. The piece looks at the risks of living next to one of the biggest nuclear plants in the U.S.—Diablo provides power for 3 million homes—as well as the benefits, and asks whether nuclear power is worth it:
Diablo Canyon’s watchdogs have long worried about the plant’s proximity to the faults, but in the wake of Fukushima, fears have escalated. Mothers for Peace, an antinuclear activist group that has opposed the operation at Diablo Canyon since the start, says its in-box has swelled with questions about safety. Sen. Sam Blakeslee, a California Republican who represents San Luis Obispo and holds a PhD in earthquake studies, says he can understand why. “This entire area is a patchwork of faults,” he says. “It was probably an imprudent location to site a nuclear power plant.”
Diablo Canyon and Fukushima have that in common–but so do many other power plants. The production of nuclear power relies on an abundance of water: That’s why all but one of America’s 104 nuclear reactors sit on oceans, lakes, or rivers. And earthquakes of varying strength have been detected near most US nuclear power plants.
Diablo Canyon has a strong safety record: It has never had a nuclear emergency or meltdown, it’s designed to withstand a 7.5-magnitude earthquake, and it routinely self-reports problems, which experts consider to be a sign that the system is working as it should. What’s more, nature has cooperated: Diablo Canyon has never been overrun by a tsunami or damaged by an earthquake.
Even so, it’s hard to shake off the echo of similar assurances–assurances now known as the “safety myth”–that the Japanese were given before Fukushima. Now, in that catastrophe’s aftermath, the fundamental question looms: How safe is safe enough when you’re talking about nuclear energy?
I don’t know the answer yet—but I do know the article is well worth a read.