Pacific Bluefin tuna caught off the coast of California have been found to have radioactive contamination from last year’s Fukushima nuclear accident.
The fish would have picked up the pollution while swimming in Japanese waters, before then moving to the far side of the ocean.
Scientists stress that the fish are still perfectly safe to eat. [editor's note: wtf?!]
However, the case does illustrate how migratory species can carry pollution over vast distances, they say.
“It’s a lesson to us in how interconnected eco-regions can be, even when they may be separated by thousands of miles,” Nicholas Fisher, a professor of marine sciences at Stony Brook University, New York, told BBC News.
All the fish examined in the study showed elevated levels of radioactive caesium – the isotopes 134 and 137.
Caesium-137 is present in seawater anyway as a result of the fallout from atomic weapons testing, but the short, two-year half-life of caesium-134 means the contamination can be tied directly to Fukushima. There is no other explanation for the isotope’s presence.
The measured concentrations were about 10 times the total caesium radioactivity seen in tuna specimens taken from before the accident.