Fukushima radiation release analyzed

FUKUSHIMA, Japan, Dec. 9 (UPI) -- Radiation levels in water discharged into the ocean from nuclear power plants peaked one month after the Fukushima disaster, U.S. and Japanese researchers say.

The study by Woods Hole Oceanographic Institution chemist Ken Buesseler and Japanese colleagues found the level of radioactivity in discharges into the ocean from the Fukushima Dai-Ichi nuclear power plants were not a direct threat to human or marine life, but the effect of accumulated radiation in marine sediments is not known.

The release of radioactivity from Fukushima, both as atmospheric fallout and direct discharges to the ocean, persisted into July, and constitute the largest accidental release of radiation to the ocean in history, the researchers said.

Buesseler was awarded a rapid-response grant from the National Science Foundation to establish baseline concentrations in the Atlantic and Pacific oceans.

"Understanding and management of the long-term geochemical fate and ecological consequences of radiochemical contamination of the sea is dependent on our knowledge of the initial conditions," Don Rice, director of NSF's Chemical Oceanography Program, said in a foundation release Friday. "Acquiring that knowledge depends on our ability to deploy experts to the scene with minimal delay."