Radiation in the Pacific
Written by Faith Anderson on February 22, 2012
Levels of Radioactive Materials 1,000 Times Higher Than Before
According to the report, the water that was tested showed readings of up to 1,000 times higher than previous testings. Fortunately, the results for the substance cesium-137 are far below the levels that are generally considered harmful, either to people, marine animals or to seafood, said Ken Buesseler of the Woods Hole Oceanographic Institution in Massachusetts and chief scientist for the crew that collected the data. The results are for water samples taken in June, about three months after the disaster occurred, Buesseler said. In addition to thousands of water samples, researchers also sampled plankton and fish, and found cesium-137 levels well below the legal health limit.
Radioactive Contamination of the Ocean Expected to Continue
“We’re not over the hump yet,” said Buesseler, referring to future radioactive contamination of the ocean, because of continued leakage from the plant. The highest readings last June were not always from locations closest to the plant, because swirling ocean currents formed concentrations of the material. Most of the cesium-137 detected during the testing probably entered the ocean from water discharges rather than atmospheric fallout, Buesseler said. Cesium-137 also wasn’t the only radioactive substance released from the plant, but it’s of particular concern because its half-life is 30 years, which means it remains in the environment for a long time.
Scientists Expect Radiation Situation to Improve
According to Hartmut Nies, of the International Atomic Energy Agency, Buesseler’s findings were not surprising, given the vastness of the ocean and its ability to absorb and dilute materials. “This is what we predicted,” Nies said. “This is good news.” In fact, Nies said, the water’s cesium-137 concentration has been so diluted that just 20 miles offshore, “if it was not seawater, you could drink it without any problems.” Scientists expects levels of radioactive materials to continue to decrease over time. “We still don’t have a full picture,” Nies said, “but we can expect the situation will not become worse.”