Last week, we looked at evidence gathered in Seattle of tiny amounts of radioactive material that had made its way across the Pacific from the stricken nuclear reactors in Fukushima, Japan.
So it's no surprise that similar evidence is turning up further down the coast in San Francisco.
Between 16 and 26 March, Eric Norman and pals at the department of nuclear engineering at UC Berkeley placed buckets at various locations in the Bay Area to gather rain water (the earthquake that triggered the accident occurred on 11 March). They then analysed the water they collected, looking for the tell tale gamma rays from radioactive stuff.
As expected, they found it. "Gamma ray spectra measured from these samples show clear evidence of fission products - iodine-131 and132, tellurium-132 and cesium-134 and 137," say Norman and co.
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