Bluefin tuna that was caught off the southern California coast was found to contain radiation from the Fukushima nuclear plant that was destroyed after the earthquake and subsequent tsunami last year, but scientists insist that the tuna is still safe for consumption.
Scientists conducted the study after the earthquake to see if there would be any contamination of fish that were in the area during the nuclear plant's meltdown.
The study was published this week by the Proceedings of the National Academy of Sciences. The study explained that researchers found "modestly elevated levels" of two radioactive isotopes in 15 bluefin tuna caught off the coast of San Diego, California in August 2011.
"We were quite surprised to find that bluefin carried both of these isotopes," the study's co-author Nicholas Fisher, of New York's Stony Brook University, told CNN.
Researchers found small amounts of radioactive cesium-134 and cesium-137 in the 15 tuna caught. They then compared the findings to other tuna species, such as yellowfin, which tend to stay in the eastern pacific.
"These findings indicate that Pacific Bluefin tuna can rapidly transport radionuclides from a point source in Japan to distant ecoregions and demonstrate the importance of migratory animals as transport vectors," it said.
The researchers stressed that bluefin tuna was still safe to eat and explained that all fish have naturally occurring levels of radiation like potassium-40. Scientists also explained that the new radiation found was far less than the naturally occurring isotopes.
"I personally would not hesitate to eat the tuna that were caught off the coast of California," Fisher said.
In March 2011 a 9.0-magnitude earthquake and tsunami killed tens thousands of people and crippled the cooling systems at the Fukushima plant, causing several of its reactors to melt down.
Radiation leaked into the sea, air and land around the power plant which has prevented tens of thousands of people from returning.