Limited sampling in early 2016 by the Alaskan Department of Environmental Conservation failed to detect evidence of Fukushima derived contamination in commercially important fish species. While only 7 individual fish were analyzed for gamma emitting isotopes the results from Alaska are consistent with more intensive sampling carried out by the Integrated Fukushima Ocean Radionuclide Monitoring (InFORM) project based in British Columbia Canada. Thus far the amount of Fukushima derived contamination in northeast Pacific seawater and the food of culturally and economically important fish do not lead to levels that are known to pose a significant health risk to consumers. The following summary was prepared by Dr. Jonathan Kellogg.
No Fukushima contamination was found in any of the 7 fish Alaskan fish samples that were collected during February and March of 2016. The results, released on the Department of Environmental Conservation website, show that the herring, cod, and pollock sampled did not have any detectable levels of 131I, 134Cs (the Fukushima fingerprint radionuclide with a half-life of ~2 years) or 137Cs in the tissues. These samples follow on their similar results from 2015 and are part of the network of institutions monitoring for Fukushima radiation in marine waters and seafoods.
InFORM sampling of BC salmon and steelhead is currently underway. We anticipate collecting >100 samples from fish returning to most major BC fisheries. Results will be made public as soon as possible.
Note: The average minimum detectable concentrations for these Alaskan samples on this gamma spectrometer were 8.8 Bq kg-1, 2.1 Bq kg-1, and 1.8 Bq kg-1 respectively. For comparison, the intervention levels for 131I = 170 Bq kg-1 and 134Cs + 137Cs = 1200 Bq kg-1 according to the US Food and Drug Administration.