Levels of radioactive plutonium in Earth’s stratosphere from nuclear tests and accidents is higher than previously thought, but probably not dangerous to humans, scientists in Switzerland said Tuesday. It was previously thought that plutonium radionuclides — radioactive atoms which can take decades or thousands of years to degrade — were present in the stratosphere only at negligible levels. It was also believed that levels of these pollutants were higher in the troposphere, the layer of […]
Reported by Raw Story 7 hours ago.
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