Tiny amounts of an isotope, Iodine 131, from Japan have been detected in rainwater samples collected from the roof of a campus building in Cleveland, US.
Gerald Matisoff, professor of geology at the Case Western Reserve University, who has detected the presence of the isotope, said it presents no danger to human health.
He estimated that the level of radiation is about one-tenth that of natural background radiation. "In theory, the Iodine 131 could have come from any radioactive waste processing facility," Matisoff said, according to a Case Western statement.
"But, we know it's from Japan. The isotope is being seen worldwide," he said. Matisoff and graduate student Mary Carson collect water on the roof of the A.W. Smith Building, on the Case Western campus, to monitor the particulates being carried in rain into Lake Erie.
Carson ran the analysis on Friday and Matisoff verified the findings.