Next time you head over to your local sushi joint you may want to take a Geiger counter with you. According to researchers at the National Academy of Sciences radiation from the Fukushima disaster has found its way across a 6,000 mile ocean to the coasts of California:
Across the vast Pacific, the mighty bluefin tuna carried radioactive contamination that leaked from Japan’s crippled nuclear plant to the shores of the United States 6,000 miles away — the first time a huge migrating fish has been shown to carry radioactivity such a distance.
“We were frankly kind of startled,” said Nicholas Fisher, one of the researchers reporting the findings online Monday in the Proceedings of the National Academy of Sciences.
The levels of radioactive cesium were 10 times higher than the amount measured in tuna off the California coast in previous years. But even so, that’s still far below safe-to-eat limits set by the U.S. and Japanese governments.
But scientists did not expect the nuclear fallout to linger in huge fish that sail the world because such fish can metabolize and shed radioactive substances.
To rule out the possibility that the radiation was carried by ocean currents or deposited in the sea through the atmosphere, the team also analyzed yellowfin tuna, found in the eastern Pacific, and bluefin that migrated to Southern California before the nuclear crisis. They found no trace of cesium-134 and only background levels of cesium-137 left over from nuclear weapons testing in the 1960s.
The results “are unequivocal. Fukushima was the source,” said Ken Buesseler of the Woods Hole Oceanographic Institution, who had no role in the research.
Despite warnings from various international organizations about the dangers posed from radiation contamination to global food supplies, researchers funded by the US and Japanese governments maintain that the food is safe to eat.