[...] low levels of radioactive cesium from Japan’s Fukushima Daiichi nuclear accident turned up in fish caught off California in 2011, researchers reported Monday.

Tissue samples taken from 15 bluefin caught in August, five months after the meltdowns at Fukushima Daiichi, all contained reactor byproducts [...]

But neither thought they were likely to find cesium at all, they said. And since the fish tested were born about a year before the disaster, “This year’s fish are going to be really interesting,” Madigan said.

“There were fish born around the time of the accident, and those are the ones showing up in California right now,” he said. “Those have been, for the most part, swimming around in those contaminated waters their whole lives.”

[...]

And if any fish are found with dangerous levels of radioactive material in their tissue, “It would be our responsibility to report it right away,” he said.