A Map of Fukushima's Radiation Risks
by Jocelyn Kaiser on 22 April 2011, 11:17 AM
Credit: U.S. DOEA new map from the U.S. Department of Energy (DOE) shows the long-term radiation risks to people living near Japan's ailing Fukushima Daiichi nuclear plant.
DOE-sponsored aerial surveys began measuring radiation around the plant about 1 week after the reactor was hit by a tsunami on 11 March. The maps released before, however, have been reporting current radiation levels. Now DOE has projected what the first-year dose would be to people living around the plant up to about 80 kilometers away (see map). The analysis, released on 18 April, takes into account the fact that radiation levels are slowly falling—mainly due to the decay of iodine-131, which has a half-life of 8 days. It shows the high end of external exposures—what people would receive if they didn't evacuate after the accident and didn't follow advice to stay indoors.