Wednesday, August 1, 2012

カナダで食べるシーフード大丈夫? Are seafood in Canada really safe?


After Fukushima, fish tales

By ALEX ROSLIN, Special to The Gazette

January 13, 2012 9:06 PM

After the world’s worst nuclear accident in 25 years, authorities in Canada said people living here were safe and faced no health risks from the fallout from Fukushima.

They said most of the radiation from the crippled Japanese nuclear power plant would fall into the ocean, where it would be diluted and not pose any danger.

Dr. Dale Dewar wasn’t convinced. Dewar, a family physician in Wynyard, Sask., doesn’t eat a lot of seafood herself, but when her grandchildren come to visit, she carefully checks seafood labels.
Dale Dewar医師は納得していませんでした。サスカチワン州、Wynyardの開業医、Dewar医師は、自分は海産物はあまり食べないけれど、孫たちが尋ねてきたときは、海産物のラベルを注意深く確認しています。

She wants to make sure she isn’t serving them anything that might come from the western Pacific Ocean.

Dewar, the executive director of Physicians for Global Survival, a Canadian anti-nuclear group, says the Canadian government has downplayed the radiation risks from Fukushima and is doing little to monitor them.
Dewar医師は、 (IPPNWのカナダ支部である)グローバルサバイバル医師団(PGS)の取締役であり、カナダ政府が福島からの放射能の危険性を小さく見せようとし、ほとんどモニタリングをしていないのだと言います。

“We suspect we’re going to see more cancers, decreased fetal viability, decreased fertility, increased metabolic defects – and we expect them to be generational,” she said.

And evidence has emerged that the impacts of the disaster on the Pacific Ocean are worse than expected.

Since a tsunami and earthquake destroyed the Fukushima Daiichi Nuclear Power Plant last March, radioactive cesium has consistently been found in 60 to 80 per cent of Japanese fishing catches each month tested by Japan’s Fisheries Agency.

In November, 65 per cent of the catches tested positive for cesium (a radioactive material created by nuclear reactors), according to a Gazette analysis of data on the fisheries agency’s website. Cesium is a long-lived radionuclide that persists in the environment and increases the risk of cancer, according to the United States Environmental Protection Agency, which says the most common form of radioactive cesium has a half-life of 30 years.

The Canadian Food Inspection Agency, which monitors food safety, says it is aware of the numbers but says the amounts of cesium detected are small.

“Approximately 60 per cent of fish have shown to have detectable levels of radionuclides,” it said in an emailed statement.

“The majority of exported fish to Canada are caught much farther from the coast of Japan, and the Japanese testing has shown that these fish have not been contaminated with high levels of radionuclides.”

But the Japanese data shows elevated levels of contamination in several seafood species that Japan has exported to Canada in recent years.

In November, 18 per cent of cod exceeded a new radiation ceiling for food to be implemented in Japan in April – along with 21 per cent of eel, 22 per cent of sole and 33 per cent of seaweed.

Overall, one in five of the 1,100 catches tested in November exceeded the new ceiling of 100 becquerels per kilogram. (Canada’s ceiling for radiation in food is much higher: 1,000 becquerels per kilo.)

“I would probably be hesitant to eat a lot of those fish,” said Nicholas Fisher, a marine sciences professor at the State University of New York at Stony Brook.
「これらの魚を多く食べることには抵抗があると思います。」とストーニーブルックのニューヨーク州立大学、海洋科学の教授、Nicholas Fisher氏は話しました。

Fisher is researching how radiation from Fukushima is affecting the Pacific fishery. “There has been virtually zero monitoring and research on this,” he said, calling on other governments to do more radiation tests on the ocean’s marine life.

“Is it something we need to be terrified of? No. Is it something we need to monitor? Yes, particularly in coastal waters where concentrations are high.”

Contamination of fish in the Pacific Ocean could have wide-ranging consequences for millions.

The Pacific is home to the world’s largest fishery, which is in turn the main source of protein for about one billion people in Asia alone.

In October, a U.S. study - co-authored by oceanographer Ken Buesseler, a senior scientist at the non-profit Woods Hole Oceanographic Institution in Woods Hole, Mass., - reported Fukushima caused history’s biggest-ever release of radiation into the ocean - 10 to 100 times more than the 1986 Chernobyl nuclear catastrophe.
10月のアメリカの研究-マサチューセッツ州、非営利団体ウッズホール海洋研究所のベテラン科学者である海洋学者、Ken Buesseler氏と共同著作された-では、福島が、海洋に放出された放射能が、史上最大のものだ-1986年のチェルノブイリ放射能惨事より10-100倍以上-と報告されています。

“It’s completely untrue to say this level of radiation is safe or harmless,” said Gordon Edwards, president of the Canadian Coalition for Nuclear Responsibility.
「この放射能レベルが安全だとか、害がない、と言うのは、全く持って真実ではない。」と、カナダ原子力責任連合の代表であるGordon Edwards氏は言います。

Edwards, who is also a math professor at Vanier College, said Fukushima has highlighted how lackadaisical Canadian authorities are about radiation risks - the result, he says, of the influence of Canada’s powerful nuclear industry.

“The reassurances have been completely irresponsible. To say there are no health concerns flies in the face of all scientific evidence,” said Edwards, who has advised the federal auditor-general’s office and Ontario government on nuclear-power issues.

Other Fukushima impacts have been unexpected, too. The first debris swept into the sea by the tsunami reportedly started to wash ashore on the west coast in mid-December, a year earlier than scientists and authorities predicted.


Residents of Vancouver Island, Alaska and the U.S. Pacific coast have said they’ve found large quantities of bottles, cans, lumber and floats.

The debris is part of 18 million tonnes of debris from Japan floating across the Pacific-taking up an area thought to be twice the size of Texas.

The impact of the debris on the Pacific is unclear. Much of it is expected to eventually join an already massive patch of existing garbage floating in the Pacific gyre.
瓦礫が太平洋に与える影響は、明らかではありません。その多くが、最終的に、既にごみが浮いている北太平洋旋廻の「太平洋ゴミベルト に合流すると思われています。



The arrival of the debris on the west coast also appears to have caught Canadian authorities off guard.

“What debris are you talking about?” Health Canada spokesman Gary Holub asked when contacted for a comment this week.
「なんの瓦礫のことを言っているのですか?」と、今週コメントを求めたところ、ヘルス・カナダのスポークスマン、Gary Holub氏はたずねました。

“Debris from Japan is not expected on the west coast of Canada for another year.”

He asked a reporter to email him media stories about the debris. Later, Holub emailed a statement saying “there has been no official confirmation that the source of this debris is from the tsunami in Japan.”

He said, “It is ‘highly unlikely’ the debris will be radioactive and that Health Canada will await scientific data before deciding whether to test any of it.”

It’s also unclear how the debris will impact fish in the Pacific.
But there is a good chance Canadians have already eaten some of the types of fish most likely to be contaminated with cesium, based on the Japanese fisheries data.

Japan exported $76 million of food products to Canada in 2010, including $13 million of fish and crustaceans. No figures were available for 2011.

The Gazette analyzed the Japanese fisheries data for 22 seafood species that Japan has exported to Canada in recent years.

Some cesium was found in 16 of these 22 species in November, the last full month for which data was available.

Cesium was especially prevalent in certain of the species:

73 per cent of mackerel tested 

91 per cent of the halibut

92 per cent of the sardines

93 per cent of the tuna and eel

94 per cent of the cod and anchovies

100 per cent of the carp, seaweed, shark and monkfish

Some of the fish were caught in Japanese coastal waters. Other catches were made hundreds of kilometres away in the open ocean.

There, the fish can also be caught by fishers from dozens of other nations that ply the waters of the Pacific.

Yet, Japan is the only country that appears to be systematically testing fish for radiation and publicly reporting the results.

CFIA is no longer doing any testing of its own. It did some radiation tests on food imports from areas of Japan around the stricken nuclear plant in the weeks after the Fukushima accident.

Only one of the 169 tested products showed any radiation. CFIA stopped doing the tests last June, saying they weren’t needed.

“The quantities of radioactive material reaching Canada are very small and within normal ranges,” CFIA spokesperson Lisa Gauthier said in an emailed statement.
「カナダに到達した放射性物質の量はとても少なく、平常範囲なのです。」とCFIAのスポークスマン、Lisa GauthierさんはEメールで述べました。

“They do not pose any health risk to Canadians, the food we eat or the plants and animals in Canada.”

In August, CFIA also tested a dozen samples of fish caught in B.C. coastal and inland waters. None of those tests found any radiation.

CFIA said it has no plans to do any other radiation tests on fish in the Pacific or imports from other nations that fish in the ocean, including Japan.

CFIA now relies on Japanese authorities to screen Japanese food exported to Canada.

But Japan’s monitoring of food has come under a storm of criticism from the Japanese public after food contaminated with radiation was sold to consumers.

Photo from NHK Special

A Canadian seafood industry official was surprised when told CFIA doesn’t plan any more tests of Pacific fish.

“It is certainly our expectation that the CFIA will test again this year,” said Christina Burridge, executive director of the B.C. Seafood Alliance.
「今年また、CFIAが調査するとばかり思っていました。」と、BC集漁業組合の代表、Christina Burridgeさんは言いました。

The alliance is an umbrella of Pacific seafood harvesting associations whose member firms generate about $700 million in yearly revenues.

Burridge said CFIA promised her group last spring it would test Pacific salmon and tuna returning to B.C. fishing grounds in 2012 and 2013 because of the possibility those fish could have migrated close to Japan.

“We all agreed that if there was any risk of contamination, it would be in 2012 and 2013,” she said.

She wouldn’t comment on the Japanese fisheries data, which she hadn’t seen previously. But she said of the data: “It would reinforce our expectation that the CFIA would test this year.

“We want to be able to assure our customers that our expectation that there will be no increase in detectable levels (of radiation) is true,” she said.

She said she based this expectation on “a general belief that contamination will be limited to the coastal waters off Japan.”

But despite this belief and the importance of the Pacific fishery, few studies exist on how Fukushima affected marine life.

One of those studies found that fish and crustaceans caught in the vicinity of Fukushima in late March had 10,000 times more than so-called safe levels of radiation. The study, published last May in the journal Environmental Science & Technology, also said macroalgae had 19,000 times the safe level.
ある研究では、3月末に福島近海で捕れた魚と甲殻類に、いわゆる安全な放射能レベルよりも1万倍高い値が見つけられました。5月末に「Environmental Science & Technology環境科学技術」という雑誌に発表されたその研究は、海藻に安全レベルの1万9千倍の汚染があった、と述べています。

Those levels were measured before the Japanese utility that runs the crippled nuclear plant dumped 11,000 tonnes of radioactive water into the Pacific in April and additional leaks that have released hundreds of tonnes more.

But since that early study, little research has been published on the topic.

“People want to know what’s happening with the cesium and how much is in the fish, but we don’t know. It’s frustrating,” said oceanographer Buesseler.

“It’s disconcerting how big of an event Fukushima was and how little data are out there. No one has taken responsibility for studying this in a single agency (in the U.S.), even though we also have reactors on the coast and other events could happen,” he said.

SUNY’s Fisher agrees: “In the U.S., it’s very difficult to acquire funding to do that work. A lot of people are very frustrated. Funding agencies are already spread incredibly thin, and they were not prepared for this,” he said.
SUNYの Fishers氏も同意します。「アメリカでは、このような調査に基金を獲得するのがとても難しいのです。多くの人がとても失望しています。」基金提供機関は既に信じがたいほど割りあてが乏しく散りばめられ、この件については準備されていなかったのです。」

A radiation detector is used in Manhattan’s Sushi Yasuda restaurant in April. The restaurant has found no radiation contamination since it began using the detector as a precautionary measure in response to consumer concerns over possible contamination of seafood after the nuclear accident in Japan.
Photograph by: Mario Tama, Getty Images file photo

After governments refused to provide funds, Buesseler, Fisher and other scientists secured funds from a private foundation for a research voyage in the Pacific to gather radiation data on fish, plankton and water.

Fisher can’t discuss his findings because they aren’t published yet. He expects to send them for publication in coming weeks.

Buesseler has already reported some results from the 15-day cruise last May and June.

He co-authored the study in October that said cesium levels in the Pacific had gone up an astonishing 45 million times above pre-accident levels. The levels then declined rapidly for a while, but after that, they unexpectedly levelled off.

In July, cesium levels stopped declining and remained stuck at 10,000 times above pre-accident levels.

It meant the ocean wasn’t diluting the radiation as expected. If it had been, cesium levels would have kept falling. The finding suggested radiation was still being released into the ocean long after the accident in March, Buesseler said in an interview.

“It implies the groundwater is contaminated or the facility is still leaking radiation.”

The Japanese fisheries data seems to support this conclusion. Far from declining, contamination levels in some species were flat or even rose last fall, including species that Japan exports to Canada like skipjack tuna, cod, sole and eel.

In November, the average Japanese catch had 111 becquerels of cesium per kilogram – above the new radiation ceiling of 100 becquerels per kilo that Japan has announced it will implement for food this spring.

The November level declined from a peak level of 373 becquerels per kilo last April. But it was an increase from the October average of 78 becquerels per kilo.

Such persistently elevated levels of radiation warrant more monitoring and research, Fisher said. “It’s not something we can easily dismiss.”

Photo from NHK Special

Continuing radiation leaks from Fukushima could be to blame, he said. Another culprit, he said, may be a phenomenon called biomagnification – the tendency for radiation concentrations to increase in species that are farther up the food chain.

About 2.7 per cent of the fish catches also exceeded Japan’s existing ceiling for food of 500 becquerels per kilo. That was also up from one per cent in October.

In November, 0.8 per cent of Japanese catches exceeded Canada’s ceiling of 1,000 becquerels per kilo, up from 0.2 per cent in October.

But food with radiation below these limits can still pose health risks, Edwards believes. “There is no safe level of radiation. They should be making every effort to monitor food.”

© Copyright (c) The Montreal Gazette

I tried to measure some foods with my Geiger counter.

(I saw someone measuring like this at YouTube, but I do not think this is the good way to measure food)

on my kitchen counter...


Pickled plum (bought at Japanese store in Vancouver)


Migrating Sockeye Salmon (bought at Superstore)


Whole Wheat bread (baked at Burnaby Safeway bakery)


Background in the kitchen was 0.08-0.11 microSv/hour
Right below the drainage outside was 0.05-0.08 microSv/hour

Average background radiation in Burnaby in 2010 was

0.49 microSv/day

Is it 0.02 microSv/hour?

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