Radioactive cesium found in plankton off N-plant

High concentrations of radioactive cesium have been found in plankton from the sea near the Fukushima Daiichi Nuclear Power Plant.

Researchers from Tokyo University of Marine Science and Technology collected plankton in waters up to 60 kilometers from the coast of Iwaki City in July. They found 669 becquerels per kilogram of radioactive cesium in animal plankton from waters 3 kilometers offshore.

They say a wide range of fish feed on animal plankton and that the contamination could accumulate in the food chain and have a more serious impact when it gets into relatively large fish.

The research group's leader, Professor Takashi Ishimaru, says the plankton were so heavily contaminated because sea currents continuously carried contaminated water southward from the nuclear plant. He says detailed studies are needed to determine how long the effect on fish will continue.

Cesium detected in 4% of tested rice

Radioactive tests on rice have been completed in more than half of the Tohoku and Kanto regions, and radioactive cesium has been detected in 4 percent of the samples. But the highest level detected so far is about a quarter of the government's safety limit. Based on the interim results, shipments of rice have started in municipalities in 15 prefectures. A preliminary examination is conducted while the rice is still growing and another test is carried out after the harvest. Rice can only be shipped if the amounts of cesium in the post-harvest test are below the government-set safety limit of 500 becquerels per kilogram in all the locations within a municipality. Preliminary tests have been completed in 7 prefectures, but not in Fukushima or Miyagi. Radioactive cesium has been detected in 72 places so far, including 64 locations in Fukushima Prefecture, where the Fukushima Daiichi power plant is located. But the highest level detected was 136 becquerels per kilogram, which is about a quarter of the government's safety limit. The main test is being conducted in 17 prefectures, and has been completed in more than half of them. Radioactive materials were detected in rice harvested in 22 locations. But the highest level detected so far is 101.6 becquerels per kilogram, or one fifth of the government's safety limit. With the preliminary and main tests combined, the results are known for more than 60 percent of the test locations. Radioactive materials have been detected in 94 locations, or 4.3 percent of the total. Shipments of rice have started in municipalities in 15 prefectures, including all 52 municipalities in Chiba Prefecture. In Fukushima Prefecture, shipments of ordinary rice have started in 2 municipalities, and those of early-harvested rice in 20 municipalities.

Tokyo traces cows from contaminated farm

The Tokyo Metropolitan government has begun tracing beef from 6 cows shipped from a Fukushima farm where 11 other cows were found contaminated with high levels of radioactive cesium.

On Friday, tests detected 1,530 to 3,200 becquerels per kilogram of cesium in beef from the 11 cows raised in Minami Soma city, about 20 kilometers from the crippled Fukushima Daiichi nuclear power plant. The national safety limit is 500 becquerels. Tokyo ordered the beef to be removed from distribution.

But beef from 6 cows shipped from the farm to
Tokyo and Tochigi in May and June are believed to have already made it to market without radiation testing. Tests were supposed to have been conducted at the production site.
Tokyo plans to collect the beef for examination, if it can locate it along the distribution routes.

The Tokyo Metropolitan government is calling for tests to be conducted at production sites. Tokyo says it's difficult to check all the cows shipped to the city.
Sunday, July 10, 2011 07:3