The authors of the Oregon State University study say a sample of albacore tuna caught off the coasts of Oregon and Washington state have increased, but still small, levels of radioactivity -- a result of Japan's 2011 Fukushima nuclear disaster.

The researchers tested different parts of 26 Pacific albacore tuna. About half of the test subjects were caught between 2008 and the March 2011 nuclear meltdown, while the others were caught and tested between the accident's aftermath and 2012. Certain radioactive isotopes tripled in that tuna specimens' loins, carcasses and guts in the wake of the disaster.

Even at triple their normal levels, the scientists point out that the isotopes are barely detectable -- trace amounts that remain well below the safety standards set by the EPA.

"You can't say there is absolutely zero risk because any radiation is assumed to carry at least some small risk," Delvan Neville, an Oregon State graduate research assistant and lead author of the study, said in a news release. "But these trace levels are too small to be a realistic concern."

"A year of eating albacore with these cesium traces is about the same dose of radiation as you get from spending 23 seconds in a stuffy basement from radon gas, or sleeping next to your spouse for 40 nights from the natural potassium-40 in their body," Neville added. "It's just not much at all."

Levels of radioactive cesium isotopes in West Coast waters are expected to slowly increase over the summer, as ocean currents continue to carry the polluted water across the Pacific. But researchers don't expect radiation amounts to come close to broaching safe drinking levels.