A water sample taken in August from about 100 miles west of Eureka, California, has been found to contain a small amount of radiation from the 2011 Fukushima nuclear plant disaster in Japan.

“Scientists at the Woods Hole Oceanographic Institution (WHOI) found the trace amounts of telltale radioactive compounds as part of their ongoing monitoring of natural and human sources of radioactivity in the ocean,” states a news release from the institute.

“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,” said Ken Buesseler, a WHOI marine chemist, who is leading the monitoring effort. “Most people don’t realize that there was already cesium in Pacific waters prior to Fukushima, but only the cesium-137 isotope. Cesium-137 undergoes radioactive decay with a 30-year half-life and was introduced to the environment during atmospheric weapons testing in the 1950s and ’60s. Along with cesium-137, we detected cesium-134 – which also does not occur naturally in the environment and has a half-life of just two years. Therefore the only source of this cesium-134 in the Pacific today is from Fukushima.”

Basically, scientists say it’s nothing more than a curiosity or confirmation of models showing where some of that radiation will show up, but the rumors and fears surrounding radiation contamination are hard to dampen.

Fukushima Radiation Reaches U.S. Coast

This is the second time radiation from Japan has shown up on our shores. In March, we reported:

A bit of cesium-134 — a telltale kind of radiation particle expected from Japan’s 2011 Fukushima nuclear disaster — has been detected in a soil sample taken from the beach at Kilby Provincial Park up the Fraser River Valley in British Columbia, said Krzysztof Starosta, an associate professor of chemistry at Simon Fraser University. The sample was collected by a marine biologist studying spawning salmon at that point in the river. Starosta said the university has collected five other samples from the area looking for more of the radiation, but so far nothing.

Don’t drink the water?

The arrival of a “radioactive plume” sounds pretty bad, but scientists repeatedly say running for your life would be an overreaction … refusing to eat fish and avoiding beaches would be too.

In fact, the last time Mike Priddy, supervisor of Washington’s Environmental Sciences Section, and his crew tested shellfish — which is where you would expect to find contaminants, because they filter the water — they found nothing, Priddy told us in February.

“We’re not seeing anything that requires anyone to be afraid,” he said.

He added in an email exchange today:

… if the water has radioactive material in it at any level, coming into contact with it will cause the contamination to transfer. That said, the levels of radioactivity we are talking about are VERY low and pose no real health affects regardless of how you are exposed, whether you come in contact with the water or somehow casually ingest it. The levels I have seen in seawater are interesting from a scientific point of view, but well below health concerns.

Nevertheless, it’s not like a little extra radiation is good for you either. So, oceanographers and health department officials from Washington and elsewhere have been monitoring our coastline for radiation that would have come from the wrecked nuclear plant. And there has been plenty of fear- and conspiracy-mongering surrounding the radiation leak from Fukushima.

A fervor was created last winter when a video (below) purporting to show “dangerously high radiation levels” in the sands of Pacifica State Beach in California surfaced in December. That video was quickly countered by state officials, who ran tests and found that what is on the beach remains “well below any levels considered unsafe for humans,” as SFGate reported.

“There is no public health risk at California beaches due to radioactivity related to events at Fukushima,” the California Department of Public Health said. “Recent tests by the San Mateo County Public Health Department show that elevated levels of radiation at Half Moon Bay are due to naturally occurring materials and not radioactivity associated with the Fukushima incident,” it said.

Yeah, but …

Does radiation from the Fukushima nuclear disaster worry you? Yes - scientists et al. either don't know all there is to know about the risk or may not be telling us.

No - I accept that the amount of radiation making it to our shores is too little to worry about. View Results

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Some of the airborne radiation — in the form of iodine-131, which is produced by an active nuclear reactor — did cross the ocean shortly after the accident, and state officials did detect small amounts in our air for a couple of months; again, nothing even close to the total amount of “excess” radiation that would be dangerous to a person, Priddy said.

Also, there were those albacore tuna caught off our coast in 2012 with small amounts of some cesium-134 in them.

“We would not have detected it normally,” Priddy said, because the amount was so small. “We had to look hard for it. … Basically, so far, we have only seen a very, very small amount of radioactivity that may have been from Fukushima.”

Use the zoom tool to see parts of the graphic:

Jake Ellison can be reached at 206-448-8334 or jakeellison@seattlepi.com. Follow Jake on Twitter at twitter.com/Jake_News. Also, swing by and *LIKE* his page on Facebook.

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