Researchers have found that bluefin tuna caught off the coast of San Diego, California are still carrying contamination from the Fukushima nuclear plant in Japan.
According to Huffington Post, this is the first time a large migratory fish species has been known to carry radiation over such a large distance – 6,000 miles from Fukushima to the West Coast of the United States. “We were frankly kind of startled…That’s a big ocean. To swim across it and still retain these radionuclides is pretty amazing,” said Nicholas Fisher, one of the researchers who has reported findings to the Proceedings of the National Academy of Sciences.
Scientists tested yellowfin tuna in the eastern Pacific Ocean and bluefin tuna that came before the leak at the nuclear plant and did not find radioactivity, ruling out other sources of the contamination in the bluefin tuna. Despite the fact that the tuna are showing levels of radioactivity 10 times higher than previous years, they are still safe to eat according to the governments of the US and Japan.
The researchers believe the tuna became contaminated while swimming in affected waters and eating prey that had become radioactive. The fish are sometimes able to metabolize a radioactive substance and eliminate it, but in this instance, they have continued to carry it from Fukushima. More tests will be conducted this summer, and scientists plans to also track migrating sea turtles, birds, and sharks.
The bluefin tuna also faces declining populations due to overfishing. As their numbers decrease, their price increases, as seen in Tokyo where a massive bluefin sold for a record $736,00 USD earlier this year. With the species struggling to survive, the National Geographic channel has received criticism for its show, Wicked Tuna, following fishermen as they catch the fish for loads of money.
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