Oceanographers have detected isotopes linked to Japan’s wrecked Fukushima nuclear plant off California’s coast, though at levels far below those that could pose a measurable health risk.
Volunteer ocean monitors collected the samples that tested positive for trace amounts of the isotope cesium-134 about 100 miles (160 kilometers) west of Eureka, California, the Massachusetts-based Woods Hole Oceanographic Institution said yesterday on its website.
Tokyo Electric Power Co’s Fukushima Dai-Ichi plant, which released “unprecedented levels” of radioactivity during the March 2011 accident, was the only conceivable source of the detected isotopes, Woods Hole oceanographer Ken Buesseler said in the release.
Explosions during the accident, during which three reactors suffered meltdowns, sent a burst of radioactivity into the atmosphere, while water used to cool overheating fuel rods flowed into the ocean in the weeks after the disaster. Lower levels of radiation have continued to trickle into the ocean via contaminated groundwater.
The radioactivity detected off the California coast was at levels deemed by international health agencies to be “far below where one might expect any measurable risk to human health or marine life,” according to Woods Hole.
It’s also more than 1,000 times lower than acceptable limits in drinking water set by the US Environmental Protection Agency, the organization said.
Tepco, as the Fukushima plant’s operator is known, said in an e-mailed statement today that the radiation’s spread had been expected and that the company has significantly improved water management at the site since the accident.
