Radioactive cesium was detected in the waters off the coast of California, about 100 miles (161 kilometers) from shore

Nov 12, 2014 19:57 GMT  ·  By

Earlier this week, researchers announced that radioactive cesium had been detected in US waters. The radiation was detected off the coast of California, some 100 miles (161 kilometers) from shore.

Information shared with the public says that the water samples found to contain trace amounts of cesium were collected and sent to the Woods Hole Oceanographic Institution in Massachusetts back in August.

Although volunteers aboard the research vessel Point Sur collected water samples from several regions nestled between Alaska and California, traces of radioactive cesium were only found off the coast of the city of Eureka.

The radioactive cesium originates from Fukushima

Having analyzed the radioactive material detected off the coast of the city of Eureka in California, scientists identified it as cesium-134, Live Science informs. Based on its profile, they say that its point of origin is the Fukushima nuclear plant in Japan.

Cesium-134 only forms in reactors and has a half-life of about two years. What this means is that it takes just a little over two years for its radioactivity to drop to half its original value. By determining the radioactivity of the cesium detected in US waters, scientists were able to find its source.

The Fukushima nuclear plant suffered a major meltdown back in 2011, when Japan was hit by a magnitude 9 earthquake and a mammoth tsunami. Almost as soon as the massive wave birthed by the shake hit the nuclear plant, three of its reactors suffered a meltdown.

As a result, the Fukushima nuclear plant began dumping substantial amounts of radioactive material into its surroundings. Eventually, the facility released so much radioactive material that the incident went down in history as one of the worst nuclear disasters ever.

No reason to worry about the cesium in US waters

According to Ken Buesseler, a marine chemist currently employed by the Woods Hole Oceanographic Institution in Massachusetts, radioactive cesium originating from Japan's Fukushima nuclear plant is present in Californian waters in very low concentrations.

More precisely, he says that the water samples collected and analyzed contained about 1,000 times less of this compound than the limit for drinking water set in place by the US Environmental Protection Agency. Otherwise put, people can still go swimming and fishing off the coast of Eureka.

“We detected cesium-134, a contaminant from Fukushima, off the northern California coast. The levels are only detectable by sophisticated equipment able to discern minute quantities of radioactivity,” the researcher said in a statement.

Still, the fact remains that, since Japan's Fukushima nuclear plant went haywire back in 2011 until this past summer, traces of radioactive material were never before documented this close to shore either in Canadian or in US waters.

Interestingly enough, it appears that, long before Fukushima, US waters had already contained traces of radioactive material. More precisely, scientists say that they were tainted with cesium-137, which has a half-life of 30 years, during weapons tests carried out in the 1950s.

Cesium found in Californian waters (5 Images)

Cesium-134 originating from Fukushima detected in US waters
Map shows where the radiation was detectedCesium-134 can only form in nuclear reactors
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