In this photo taken Saturday, Oct. 1, 2011, workers conduct decontamination operations at a junior high school in Hara-machi district in Minami Soma, northeastern Japan. The district borders outside of the 12-mile (20-kilometer) no-go zone designated after the March 11 disaster that damaged the Fukushima Dai-ichi nuclear power plant. Japan feared aftershocks could further damage one of the nuclear power plant's fuel pools, possibly causing spent fuel rods to melt and spew radiation within hours, according to a new document. (AP Photo/Kyodo News) JAPAN OUT, MANDATORY CREDIT, NO LICENSING IN CHINA, FRANCE, HONG KONG, JAPAN AND SOUTH KOREA
In this photo taken Saturday, Oct. 1, 2011, workers conduct decontamination operations at a junior high school in Hara-machi district in Minami Soma, northeastern Japan. The district borders outside of the 12-mile (20-kilometer) no-go zone designated after the March 11 disaster that damaged the Fukushima Dai-ichi nuclear power plant. Japan feared aftershocks could further damage one of the nuclear power plant's fuel pools, possibly causing spent fuel rods to melt and spew radiation within hours, according to a new document. (AP Photo/Kyodo News) JAPAN OUT, MANDATORY CREDIT, NO LICENSING IN CHINA, FRANCE, HONG KONG, JAPAN AND SOUTH KOREA
In this photo taken Tuesday, Oct. 11, 2011 and released Saturday, Oct. 15, 2011 by Tokyo Electric Power Co., plastic bags, containing protective clothing used by workers battling the nuclear disaster at TEPCO's Fukushima Dai-ichi plant, are piled up in a roofed soccer training ground in the J-Village, an athlete's village now serves as base camp for the workers, in Hirono, Fukushima Prefecture, northeastern Japan. TEPCO has not yet decided measure to dispose these low-level radioactive waste properly, local media said. (AP Photo/Tokyo Electric Power Co.) EDITORIAL USE ONLY
In this photo taken Friday, Oct. 14, 2011 and released by Tokyo Electric Power Co., a piece of a roof for a huge iron tent is lowered by a crane to cover Unit 1 reactor building at the crippled Fukushima Dai-ichi nuclear power plant in Okuma, Fukushima Prefecture, northeastern Japan. Officials hope the tent covering Unit 1, one of the reactors worst-hit by the March 11 earthquake and tsunami, will keep leaked radioactive materials from spreading, prevent rainwater seepage and offer a barrier from further leakage. (AP Photo/Tokyo Electric Power Co.) EDITORIAL USE ONLY
NEW YORK (AP) ? The Fukushima nuclear disaster released twice as much of a dangerous radioactive substance into the atmosphere as Japanese authorities estimated, reaching 40 percent of the total from Chernobyl, a preliminary report says.
The estimate of much higher levels of radioactive cesium-137 comes from a worldwide network of sensors. Study author Andreas Stohl of the Norwegian Institute for Air Research says the Japanese government estimate came only from data in Japan, and that would have missed emissions blown out to sea.
The study did not consider health implications of the radiation. The long-term effects of the nuclear accident are unclear because of the difficulty of measuring radiation amounts people received.
In a telephone interview, Stohl said emission estimates are so imprecise that finding twice the amount of cesium isn't considered a major difference. He said some previous estimates had been higher than his.
The journal Atmospheric Chemistry and Physics posted the report online for comment, but the study has not yet completed a formal review by experts in the field or been accepted for publication.
Cesium-137 is dangerous because it can last for decades in the environment, releasing cancer-causing radiation.
Last summer, the Japanese government estimated that the March 11 Fukushima accident released 15,000 terabecquerels of cesium. Terabecquerels are a radiation measurement. The new report from Stohl and co-authors estimates about 36,000 terabecquerels through April 20. That's about 42 percent of the estimated release from Chernobyl, the report says.
It also says about a fifth of the cesium fell on land in Japan, while most of the rest fell into the Pacific Ocean. Only about 2 percent of the fallout came down on land outside Japan, the report concluded.
Experts have no firm projections about how many cancers could result because they're still trying to find out what doses people received. Some radiation from the accident has also been detected in Tokyo and in the United States but experts say they expect no significant health consequences there.
Still, concern about radiation is strong in Japan. Many parents of small children in Tokyo worry about the discovery of radiation hotspots even though government officials say they don't pose a health risk. And former prime minister Naoto Kan has said the most contaminated areas inside the evacuation zone could be uninhabitable for decades.
Stohl also noted that his study found cesium-137 emissions dropped suddenly at the time workers started spraying water on the spent fuel pool from one of the reactors. That challenges previous thinking that the pool wasn't emitting cesium, he said.
___
Online:
New study: http://bit.ly/tFURSr
Associated Pressentourage season 8 entourage season 8 avignon asn dukan diet mark sanchez faith hill
No comments:
Post a Comment
Note: Only a member of this blog may post a comment.