Saturday 19 October 2013

Pacific contamination

This article is from 2011

FDA claims no need to test Pacific fish for radioactivity
JAPAN MELTDOWN: Ocean too huge, distance too far for concern.

By RICHARD MAUER


16 April, 2011

North Pacific fish are so unlikely to be contaminated by radioactive material from the crippled nuclear plant in Japan that there's no reason to test them, state and federal officials said this week.

Even with dangerous levels of radiation reported recently just off the coast from the Fukushima reactor complex, the ocean is so huge and Alaska fisheries so far away that there is no realistic threat, said FDA spokeswoman Siobhan DeLancey. The Food and Drug Administration has oversight of the nation's food supplies.

The state's food safety program manager, Ron Klein of the Department of Environmental Conservation, said the FDA and the National Oceanic and Atmospheric Administration have demonstrated that Alaskans have no cause for worry.

"Based on the work they're doing, no sampling or monitoring of our fish is necessary," he said.

It's now a little more than a month into the nuclear crisis, and Japanese officials believe they have plugged the major leak that allowed tons of water containing highly radioactive isotopes of iodine and cesium to flow into the sea. Radiation levels went down after the alarming reports last week that they had risen to millions of times the legal limits, though on Saturday officials said the levels were rising again.

The reactors and spent-fuel-rod pools remain unstable, according to Congressional testimony Tuesday by the chairman of the U.S. Nuclear Regulatory Commission. A Japanese official said recently the crisis will continue for "a long time."

Meanwhile, the most recent results of monitoring of atmospheric fallout in Alaska show large declines since the first weeks of the crisis.

A portable radiation monitor on emergency deployment to Dutch Harbor by the EPA recorded the highest levels of iodine-131 of any of the 100-plus monitors in the EPA's RadNet system. Those readings were taken March 19, of 2.42 picocuries per cubic meter of air, and March 20, of 2.8 picocuries. Among 14 samples collected through April 2, no I-131 was detected three times, and there never was more than a tenth the level of the two elevated samples.

Similarly, the deployable monitor in Nome recorded the highest reading in the United States of cesium-131, 0.13 picocuries per cubic meter of air, on March 24. Thirteen samples since then, through April 5, detected none.

Only one air filter from the EPA monitor in Anchorage has been analyzed by the EPA lab in Montgomery, Ala. That was a sample collected March 21, and showed so little total radioactivity -- 0.006 picocuries per cubic meter of air -- that it wasn't analyzed further to learn which radioactive isotopes were present, the EPA said this week.

In addition to the filters, which in the case of the Anchorage monitor are collected and sent to Alabama two times a week, the monitors continually check for raw beta and gamma radiation and reports it to the RadNet system by satellite. In Anchorage, those readings have been consistently within the background range established before the March 11 earthquake.

Still, the city said this week it intends to sample its reservoir at Eklutna for radioactive isotopes when the ice goes out, which typically happens in mid-May.

Eklutna is critical to Anchorage's fresh water supply. Over the course of a year, the city will get about 92 percent of its water from there, with the remainder from wells, said Chris Kosinski, spokesman for the Anchorage Water and Wastewater Utility.

Iodine-131 has a half-life of about eight days, meaning that after eight days, half of a given amount will have undergone decay, producing radiation and a new stable element, xenon. Given that half-life, nearly all the iodine that would have fallen on Eklutna will have safely decayed by the time the ice melts.

But two other radioactive isotopes typically found in reactors, cesium-137 and strontium-90, have half-lives of about 30 years.

"This is brand-new stuff, but we're figuring out what we have to do," Kosinski said. "It makes sense to us to wait for the ice to melt."

In an emergency, the city could rely on well water for more than half its needs, he said. But state health officials said the levels of radiation from Fukushima are so tiny here, there is virtually no risk.

Alaska is the nearest U.S. state to Japan, and fish caught by U.S. fishermen in the 200-mile economic zone swim even closer. That has prompted some fears, particularly in Europe, that Alaska fish could be contaminated.

Tyson Fick, spokesman for the Alaska Seafood Marketing Institute, said he's urging fishermen and consumers "to settle down a bit" and look at the science conducted by federal agencies.

Fick said he believed Alaska fish, in particular in Germany and Austria, have got caught up in anti-nuclear politics. In fact, the Green Party in Germany, campaigning in regional elections, used the nuclear issue late last month to take over the state government in prosperous Baden-Wurttemberg, where conservatives had ruled for more than 50 years. There's a lot of Alaska pollock sold as fish sticks throughout Germany, and fear of them could be trouble, Fick said.

Closer to home, Dannon Southall of 10th and M Seafoods, said customers have expressed some concern, but not enough to stop buying fish. Virtually all of what he sells now -- from Alaska waters or imported -- was caught and frozen before the March 11 earthquake, he said. As new supplies replace the old, he expects imported fish especially to be tested if they come from waters close to Japan.

As for the sea in the region near Fukushimi, only octopus and eel from there had been imported to Alaska in the past, and that was mainly for sushi, he said.

DeLancey, the FDA spokeswoman, said those Japanese fishermen were disrupted by the tsunami and are no longer fishing anyway.

As for U.S. fish, she said, "We have not been doing any testing. We've been working with NOAA to keep an eye on U.S. waters, to see if there is any cause for alarm, and we do have the capability to begin testing if that does occur."

Asked to explain what kind of monitoring was taking place in the ocean, DeLancey said, "You would have to talk directly to NOAA ... I don't really want to speak for another agency."

But NOAA fisheries spokeswoman Kate Naughton declined to answer questions and referred a reporter back to DeLancey and the EPA.

DeLancey said that so far, there's no reason for concern about Fukushima. The radioactive materials in the water near Fukushima quickly become diluted in the massive volume of the Pacific, she said. Additionally, radioactive fallout that lands on the surface tends to stay there, giving the most unstable ones isotopes like iodine time to decay before reaching fish, she said.

Some imported fish are tested, she said, but those also appear safe


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