Wednesday, April 13, 2011

Rising fears of Fukushima impact

"Where do those prawns come from?" a female shopper asks the assistant in a Beijing branch of Carrefour. "Tianjin," the shop assistant responds. "Oh, OK," the woman says, "I'll leave it." The assistant calls after her. "They're fresh," he exclaims. But the shopper was not convinced. "I think we should only buy river fish in future," she tells her husband, her concerns heightened over radioactivity flowing from the stricken Fukushima nuclear plant in Japan. Tianjin lies on the east coast of China, 116 km to the south-east of Beijing and over 2,000 km from Fukushima. But despite the distance from Japan, consumers are concerned about the spread of radiation.

It is not only shoppers who are worried. This week the Chinese government raised its concerns over the disaster, prompting Premier Wen Jiabao to call Japanese Prime Minister Naoto Kan [Xinhua]. The premier's phone call followed an earlier official notice sent to Japan. In a statement posted on the ministry's website on Friday, Foreign Ministry spokesman Hong Lei said China hoped that Japan would take concrete measures to protect the marine environment and asked that information be provided in an accurate and timely fashion [Seattle Times].

Despite Chinese concerns, authorities insist that thus far the risks posed to the public are small. Nonetheless the Chinese Ministry of Environmental Protection, which also acts as the nuclear safety watchdog, said the "long-term consequences of the Fukushima accident cannot be ignored", and that the government would continue assessing its impact on China's environment and seas.

Radiated water issued from Fukushima "is likely to have a certain impact on aquatic life" the ministry said in a statement, which was dated Tuesday but appeared on the government website on Wednesday.

"Its impact on our country's environment has been small, equivalent to about one percent of the impact of the Chernobyl nuclear accident on our country," said the ministry [Xinhua / Reuters].

The statement came as Japanese authorities reassessed the crisis upgrading the severity to a level 7, on a par with the Chernobyl nuclear accident which happened 25 years ago.


Japan insists that the raising of the status of the accident did not mean there had been a change in circumstances, but merely a reassessment of all the available data concerning the situation at the plant.

Several explosions, fires and leaks have poured a significant quantity of radioactive substances into the environment, though beyond the immediate vicinity of the Fukushima plant officials insist there is no immediate risk to human health.

Small amounts of plutonium have been found close to the plant, but have not been detected further afield. However, iodine 131 and caesium 137 have been located hundreds of kilometres from Fukushima.

China says the radioactive isotope iodine 131 as well as caesium 134 and 137 were found in 22 provinces; Beijing, Shanghai, Tianjin, Chongqing, Hebei, Shanxi, Liaoning, Jilin, Jiangsu, Zhejiang, Anhui, Fujian, Shandong, Henan, Hunan, Hainan, Sichuan, Guizhou, Shannxi, Gansu, Ningxia and Xinjiang.

However Xinhua, China's state news agency, reported that the detected particles were "harmless" and that there was "no need to adopt protective measures."

There is some cause for concern however. Iodine 131 has been detected in spinach planted in Beijing, Jiangsu, Zhejiang and Shandong. The radioactive isotope was also found on lettuce and Chinese cabbage in Guangdong, Xinhua reported. Though not officially stated, it is likely that particles of radioactive caesium have also entered the food chain.

Authorities insist that the levels do not pose a threat, but some scientists are speaking out and warning of the long term effects. Helen Caldicott, president of the Helen Caldicott Foundation for a Nuclear-Free Planet and the author of Nuclear Power is Not the Answer, aired her view in the Guardian and suggests many journalists and scientists are underplaying the risks.

No safe level

Nuclear industry proponents often assert that low doses of radiation, below 100mSV, produce no ill effects and are therefore safe. But, as the US National Academy of Sciences BEIR VII report concluded, no dose of radiation is safe. Even low exposure can pose health risks. Exposure is cumulative and adds to an individual's risk of developing cancer.

While external contamination poses a relatively low risk in that decontamination may simply involve the discarding of clothes and the washing of skin, internal ingestion of radioactive particles can increase risks dramatically.

Hazardous radionuclides such as iodine 131, caesium 137, and other isotopes currently being released in the sea and air around Fukushima bio-concentrate at each step of various food chains. They build up in algae, crustaceans, small fish, bigger fish, then humans. Or they might pass through soil, grass, meat and milk, and to humans.

After they enter the body, these elements, known as internal emitters, migrate to specific organs such as the thyroid, liver, bone, and brain, where they continuously irradiate small volumes of cells with high doses of alpha, beta and/or gamma radiation. Over many years they can induce uncontrolled cell replication, often referred to as cancer. Many such nuclides remain radioactive in the environment for generations, and will ultimately cause increased incidences of cancer and genetic diseases over time.

While iodine 131 will gradually melt away having a very short half-life, other substances will persist for much longer. Caesium 137 for example has a half-life of some 30 years, and even small particles, if ingested, significantly increase a person's risk of developing cancer.

Relative risk

Some authorities suggest that while some concern is warranted, the increased risk is small given people's exposure to background radiation. After drinking water was discovered to contain small amounts of radioactive iodine 131 in Denver in the United States, the Environmental Protection Agency released a statement in an attempt to allay people's fears.

"We understand that people get concerned when we talk about radiation, but it's important to understand how these low levels compare to the radiation we experience from natural sources every day," EPA spokesman Rich Mylott said. "To put this drinking water sample into context, an infant would have to drink nearly 7,000 litres of this water to receive a radiation dose equal to just one day's worth of natural background exposure. That's exposure we all experience every day from natural sources, such as the sun and rocks and gases in the earth's crust" [Denver Post].

In the view of many environmentalists, the damage was done many years ago. Atomic tests in the 1950s spread quantities of radioactive particles around the globe and the release of a significant amount of radiation from Chernobyl and Fukushima has just added to the thin layer of radioactive particles coating planet Earth.

Several radioactive substances are already in the food chain. Radioactive polonium 210, which gained increased attention following the poisoning of Alexander Litvinenko [tvnewswatch], is contained in phosphate fertilizers and is absorbed by the roots of plants. Tobacco plants readily absorb the polonium 210, which emits alpha radiation and is estimated to cause about 11,700 lung cancer deaths annually worldwide [Independent / NYT]. However, polonium can be absorbed by other plants and has also been found in the wider food chain, especially in seafood [ACSA].

Long term effects

Any effects from the radioactive leaks at Fukushima will only be seen over time. It has taken years to assess the impact of Chernobyl on people and the environment, and there is still much argument amongst researchers over how many were affected directly and indirectly. One study suggests that nearly one million died from cancers induced by the radioactive releases, while others put the death toll at only a few hundred [Chernobyl: Consequences of the catastrophe for people and the environment].

There are still restrictions in place concerning animals affected from Chernobyl. In Britain, more than 2,000 km from the reactor, radioactive caesium was still considered high 20 years after the Russian nuclear disaster [Guardian].

As recently as 2009 the British government admitted nearly 370 farms in the country were still restricted in the way sheep are reared and land is used because of radioactive fallout from the Chernobyl [Guardian]. And today there are still restrictions in place.

Difficult decisions exist for consumers and residents close to Japan. Restaurants selling seafood, especially Japanese outlets, have seen a fall in trade in China and other Asian countries []. There have been instances of stockpiling of some foods and panic buying of salt under the misguided belief its use would protect from radioactive iodine. Some restaurants in the US are attempting to reassure customers by using Geiger counters to test fish [CBS], but this is not yet a widespread practice.

Whether the risk from radioactive particles has increased or not, the fallout from the Fukushima nuclear accident is something Earth's inhabitants will have to live with. Since nuclides have been detected worldwide, there is really nowhere to run.

tvnewswatch, Beijing, China

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