I was relieved to read that Alaskan fish has tested negative for radioactive isotopes iodine-131, cesium-137, and cesium-134. Testing in 2014, and now this year, confirms no measurable levels of these isotopes. In case anyone has forgotten why scientists are testing fish for radioactivity, it's related to the Fukushima nuclear disaster following the tsunami in Japan in 2011. Personally, I wasn't worried about radiation in my Alaska king salmon, but perhaps some people were. In 2014, scientists reported trace quantities of radiation in coastal waters off British Columbia that they believe came from Japan. But these amounts were far less than 1% of the quantity of radiation the U.S. Food and Drug Administration allows in drinking water and, in my opinion, nothing to get worked up about.
So, the underlying message is that the Fukushima disaster has not affected Pacific seafood, which is welcome news for those of us who enjoy eating fish. Scientists tested cod, halibut, herring, pollock, sablefish, and several varieties of salmon.
Unfortunately, we still have to worry about mercury contamination. Decades of improper dumping of household and industrial waste has caused mercury to leach into our waterways. Bacteria convert the mercury to methylmercury, which can build up in the body and cause health problems. Plankton eat the bacteria, small fish eat the plankton, and bigger fish eat the smaller fish. The further up the food chain, the greater the mercury concentration in fish. The Washington State Department of Health publishes an extensive guide to eating fish, for those who are interested.
A statewide mercury advisory in Washington recommends avoiding shark, swordfish, king mackerel, tilefish, or tuna steaks. This is especially a problem for pregnant women and young children, but perhaps all of us should go easy on the tuna at the sushi bar. Maybe I'll stick with salmon. It's low in mercury, radiation-free, and delicious.