Scientists in California have found large numbers of Bluefin tuna that have carried radioactive contamination leaked from Japan's earthquake-devastated Fukushima nuclear plant 6,000 miles to the U.S.
It is the first known time that a large migrating fish has been shown to carry radioactivity such a great distance.
The levels of radioactive cesium found in the tuna were ten times higher than the amount found in Bluefin tuna off the California coast just one year prior.
Experts stress that humans are in no danger of getting sick from consuming Bluefin tuna, as these levels of radioactive material are still far below the 'safe to eat' limits approved by both the United States and Japanese governments.
Still, scientists are fascinated that nuclear fallout could linger for so long in such a large fish, since such fish can easily metabolize and shed such radioactive substances as they grow larger.
Pacific Bluefin tuna can grow to a size of up to 10 feet long and weigh more than 1,000 pounds.
Scientists believe the tuna absorbed the radioactive material from swimming in contaminated waters and feeding on prey that had already been exposed. As the tuna swam towards the U.S. they were able to shed some of the radiation through metabolism, but simply weren't able to completely eradicate the substance from their systems.
Researchers plan to repeat a similar study later this summer to see if the elevated levels of radiation have persisted, or risen even higher. Be sure to check back here for those results!