科学家称日本核事故危害被严重夸大

　　Fukushima is not Chernobyl, scientists repeat, and even Chernobyl was not as deadly as popularly believed。

　　Dire warnings of radiation spreading from Japan's embattled Fukushima Daiichi nuclear power plant to deadly effect across Japan, or even to California, are likely overblown, they say。

　　Radiation is all around us, varying with the number of miles we fly, the elevation of our towns, and the minerals in our environments, scientists point out. We live with it, and most of the time it is harmless。

　　“There is an increased level of anxiety disproportionate to the actual risk,” says Jerrold Bushberg, who directs programs in health physics at the University of California at Davis. “It’s the dose that makes the poison. It’s not a binary thing。”

　　Fear and hype surround radiation, which has become something of a bogeyman in part because of popular culture. A radioactive spider bit Peter Parker and turned him into Spiderman. Bruce Banner absorbed radiation in a bomb explosion and became The Incredible Hulk. Radiation from nuclear detonations morphed a small lizard into Godzilla。

　　“It gives you subliminal messages about the capacity of radiation to do harm,” Professor Bushberg says in a telephone interview。

　　A buy-up of potassium iodide tablets, which some say guard against some effects of radiation exposure, is “premature” in America, he says, and concerns over contaminated Japanese exports are also alarmist。

　　“That’s crazy, absolutely crazy,” agrees Shan Nair, a former nuclear physicist who was one of two UK experts assisting the European Commission in the post-accident Chernobyl response. “It’s important to have a sense of proportion here。”

　　And even then, Chernobyl was a very different incident from what is now unfolding at Fukushima Daiichi. Chernobyl’s reactor lacked a containment facility, unlike the Fukushima plant, whose GE-made containment vessels have withstood both an earthquake, tsunami, and thus far, a partial meltdown。

　　When it comes to nuclear power, says Bushberg of the University of California, "there is a lot of misinformation."