Blue Fin Tuna, migrating from Japan to California, are arriving with Fukushima’s ongoing radioactive discharge.
OMGWAWDTOP DEPT (Oh My God What Are We Doing To Our Planet Department)
“Yes, Madam, the tuna is marinated at sea during its long migration from Japan to here in both Cesium-134 and Cesium-137. It’s so good, it glows.”
There was about five times the background amount of cesium 137 in the bluefin tuna they tested, but that is still a tiny quantity, Madigan said: 5 becquerels instead of 1 becquerel. (It takes 37 billion becquerels to equal 1 curie; for context, a pound of uranium-238 has 0.00015 curies of radioactivity, so one becquerel would be a truly miniscule proportion.)
Bluefin tuna spawn only in the western Pacific, off the coasts of Japan and the Philippines. As young fish, some migrate east to the California coast, where upwelling ocean water brings lots of food for them and their prey. They get to these waters as juveniles or adolescents, and remain there, fattening up.
Judging by the size of the bluefin tuna they sampled – they averaged about 15 pounds (6 kg) – the researchers knew these were young fish that had left Japanese water about a month after the accident.
Most of the radiation was released over a few days in April 2011, and unlike some other compounds, radioactive cesium does not quickly sink to the sea bottom but remains dispersed in the water column, from the surface to the ocean floor.
Fish can swim right through it, ingesting it through their gills, by taking in seawater or by eating organisms that have already taken it in, Madigan said.