Sunday, March 27, 2011
RADIATION IN FISH?
The experience of Chernobyl, as well as of smaller incidents at power plants (including in the U.S.) would argue that it is. And it is not just a question of contaminated marine fish. The Chernobyl disaster of 1986 showed that radiation can also enter rivers and lakes and show up in the fish living there. Fish is very important in the Japanese diet. Fish is also a major export commodity. It comes from a variety of sources: wild-caught ocean fish, marine aquaculture, inland fishing and inland water aquaculture.
After plowing through a number of research studies and scientific papers, I concluded that the levels of radionuclides entering a particular water body will not be the only factor in determining which fish are most likely to become contaminated. A number of other factors are also likely to be involved. One is whether the water is flowing rapidly or not. Another is the type of fish: whether it is predatory, and whether it is a bottom feeder or a surface feeder. The experience of Chernobyl suggests that fish in lakes and ponds will have higher build-up of radionuclides than the same type of fish from fast-moving rivers and streams. Predatory fish will have higher levels than fish which were not predatory. Benthic fish (those that like to lie on the bottom, such as carp - Japan's most popular fish) are more likely to pick up contamination than those fish which tend to live near the surface.
As far as I know, no contamination of seafood from Japan has been reported so far. But the chances are, that it will be soon. If so, don't panic. As I keep saying, in most countries, any radiation-contaminated fish is likely to be caught before it reaches the market. Even if it does get there, a few meals are unlikely to harm you. But if you are pregnant, and for young children, it is still better to stick to the safer fish.