A new report says 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.
The new estimate for cesium-137 comes from a worldwide network of sensors. Study author Andreas Stohl of the Norwegian Institute for Air Research says the Japanese government estimates would have missed emissions blown out to sea.
Stohl says finding twice the amount of cesium isn't considered a major difference because such measurements are so imprecise. He said some previous estimates had been higher than his. The study didn't address health effects.
The journal Atmospheric Chemistry and Physics posted the report online for comment but has not been reviewed by experts in the field or accepted it for publication.
Explore further: China insists wealthy countries should improve emission targets