Radioactive isotopes from the Fukushima nuclear disaster in Japan have been detected in the great kelp forests off the California coast, according to a new study released by researchers at Cal State Long Beach. Following the earthquake and subsequent tsunami, a wave of radioactivity traveled across the Pacific Ocean.
After the Fukushima incident last spring, Stephen Manley and Chris Lowe, biology professors at California State-Long Beach wondered how released radiation would affect giant kelp canopies, a keystone for the coastal ecosystem. What they found, low-levels of certain radioactive isotopes, seemed to have no impact on the kelp's health, but their discovery adds anxiety for those who fear the ability for nuclear fallout to have long-ranging consequences.
Iodine 131 "has an eight-day half-life, so it's pretty much all gone," Manley told the San Francisco Chronicle. "But this shows what happens half a world away does effect what happens here. I don't think these levels are harmful, but it's better if we don't have it at all."
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The San Francisco Chronicle reports:
Kelp off California was contaminated with short-lived radioisotopes a month after Japan's Fukushima Dai-ichi nuclear plant accident, a sign that the spilled radiation reached the state's coastline, according to a new scientific study.
Scientists from CSU Long Beach tested giant kelp collected off Orange County, Santa Cruz and other locations after the March 2011 accident and detected radioactive iodine, which was released from the damaged nuclear reactor.
The largest concentration was about 250 times higher than levels found in kelp before the accident.
"Basically, we saw it in all the California kelp blades we sampled," said Steven Manley, a CSU Long Beach biology professor who specializes in kelp.
The radioactivity had no known effects on the giant kelp, or on fish and other marine life, and it was undetectable a month later.
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And KPCC in California reports:
Sampling revealed high levels of Iodine 131, as well as in some fish species that feed on the kelp. Iodine 13, a radioisotope, dissipates quickly. It has no known effects on kelp or fish, and Manley and Lowe said it’s not a human health concern.
However, the Corona del Mar sample had 250 times the iodine kelp in the area usually has.
Researchers suspect that airborne radioactivity carried in rainfall ran off into the ocean there.
As a result of this work, Manley and Lowe said they now want to trace longer-lived radioactivity through the marine food web.
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