The greenling fish, caught in the small harbor by the plant damaged in the March 2011 earthquake and tsunami, contained 231,000 becquerels of radioactive cesium per pound, Kyodo News reported Friday.
If someone were to eat around 2 pounds of fish with this level they would be exposed to about 7.7 millisieverts of internal radiation, about the dose received in a full-body CT scan.
Tepco has set up a 6-foot-tall net at the seafloor of the harbor, which has been significantly contaminated with radioactive substances, to prevent bottom fish from swimming out.
During efforts by Tepco to rid the harbor of all fish, a spotbelly rockfish containing 125,000 becquerels of radioactive cesium per pound was also caught, officials said.
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