Low levels of Fukushima cesium found in West Coast tuna

http://lightyears.blogs.cnn.com/2012/05/28/low-levels-of-fukushima-cesium-found-in-west-coast-tuna/

May 28th, 2012
"Last week, the plant's owner, the Tokyo Electric Power Company, raised its estimate of the amount of radioactive material released from the plant in the first weeks of the crisis to 900,000 terabecquerels - about a fifth the size of the release from the 1986 Chernobyl disaster. A terabecquerel is equal to one trillion becquerels.

The revised figure more than two and a half times what was estimated in April 2011, when Japan declared Fukushima Daiichi a top-level event on the international scale that ranks nuclear disasters."


"Cesium-137 has a radioactive half-life of about 30 years, and traces of the isotope still persist from above-ground nuclear bomb tests in the 1950s and '60s. But cesium-134, which has a half-life of only two years, "is inarguably from Fukushima Daiichi," Stanford University marine ecologist Dan Madigan told CNN."

"Madigan said the concentrations were likely higher in smaller fish, but shrank as the bluefin grew during their migration and processed some of the cesium in their bodies. Japanese government figures estimate cesium levels in fish caught off its shores at between 61 and 168 bq/kg.
"This year's study will be much higher sample size across a greater range of fish, ages and sizes," Madigan said. And if any fish are found with dangerous levels of radioactive material in their tissue, "It would be our responsibility to report it right away," he said. "