Abstract:
The Fukushima Daiichi power station released several radionuclides into the Pacific following the March 2011 earthquake and tsunami. A total of 26 Pacific albacore (Thunnus alalunga) caught off the Pacific Northwest U.S. coast between 2008 and 2012 were analyzed for 137Cs and Fukushima-attributed 134Cs. Both 2011 (2 of 2) and several 2012 (10 of 17) edible tissue samples exhibited increased activity concentrations of 137Cs (234824 mBq/kg of wet weight) and 134Cs (18.2356 mBq/kg of wet weight). The remaining 2012 samples and all pre-Fukushima (20082009) samples possessed lower 137Cs activity concentrations (103272 mBq/kg of wet weight) with no detectable 134Cs activity. Age, as indicated by fork length, was a strong predictor for both the presence and concentration of 134Cs (p < 0.001). Notably, many migration-aged fish did not exhibit any 134Cs, suggesting that they had not recently migrated near Japan. None of the tested samples would represent a significant change in annual radiation dose if consumed by humans.
Full report:
http://pubs.acs.org/doi/abs/10.1021/es500129b
From the article:
They discovered that levels of specific radioactive isotopes did increase after the accident, although by a minute amount.
"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," Neville said.