Thanks to a group of Canadian scientists and First Nations fisheries, we’re starting to answer that question. They’ve been testing salmon caught in British Columbia and the Yukon for both cesium-134, which they haven’t expected to find because of its short half life, and cesium-137, which remains in the environment for a long time.
Of the 156 salmon caught last summer, none tested positive for 134; seven had detectable levels of cesium-137. The levels were very, very low, they say— “well below levels known to be a health risk to the salmon or human consumers,” according to Fukushim InFORM (Integrated Fukushima Ocean Radionuclide Monitoring Network), a group of scientists from various Canadian universities, Health Canada and the Woods Hole Oceanographic Institute who are monitoring the impact on North America.
The levels are “thousands of times below the maximum allowable [level] of cesium in our drinking water,” Dr. Jay Cullen, the BC scientist who started the InFORM project, told The Globe & Mail newspaper. “ In order for us to detect it, we have to use the most sensitive techniques that we have,” he said. (And because there is still cesium -137 in the Pacific from nuclear testing decades ago, they can’t be absolutely certain that Fukushima is the culprit.)
In the coming year, Fukushima InFORM will continue to monitor seawater and fish and will start to look at shellfish as well.
Meanwhile, if you’re looking for the cleanest salmon, choose pink salmon, says Dr. David Welch, a renowned expert on salmon and their migratory patterns.
Pink feed low on the food chain most of their lives, are relatively small and of all the species, live the shortest lives—completing their life cycle in two years, he says. Thus they have less time to accumulate toxins.
Unfortunately, pink is considered the trash of the family. Its flesh goes soft very easily, Welch says, so you’re not likely to find it fresh. Instead, you can buy it canned or frozen.
Interestingly, among all those samples tested, pinks were consistently clean.
photo courtesy of Holly Botner, the Jittery Cook