Zena Iovino, reporter, newscientist.com, 29 March 2011:
Plutonium was detected in soil samples taken at five locations at the Fukushima Daiichi nuclear power plant between 21 and 22 March, according to the Tokyo Electric Power Company (TEPCO). However, TEPCO says that only two of the five samples appear to contain plutonium released during the current crisis.
The two samples in question show elevated levels of plutonium-238. Though these findings grabbed headlines on Monday, experts contacted by New Scientist say that the contamination is not severe.
"I'm not going to lie awake at night worrying about these levels," says Dan Strom, staff scientist at the Pacific Northwest National Laboratory in Richland, Washington, who notes that the US Environmental Protection Agency would deem soil with this level of contamination fit for farming.
"If this site were to be used just for a recreational area - a parking lot or golf course - then you could easily have 100 times this level," Strom adds.
Jasmina Vujic, a nuclear engineer at the University of California, Berkeley, suggests that some plutonium may have spread from steam that arose when water was dumped on the damaged buildings housing the reactors to cool spent fuel rods. Read more>>