2011/10/21

If wolves could understand the risks

The American public broadcaster PBS recently aired a documentary called Radioactive Wolves. The film (the link goes to a youtube video) examines the flourishing wildlife in the Chernobyl Exclusion Zone (CEZ), and raises fascinating questions about whether this land will ever recover from the worst industrial accident in history.

While pro and anti-nuclear activists have always had extremely different conclusions about the effects of long-lasting, low-level radiation, a comment by the director of Radioactive Wolves, Klaus Feichtenberger, offers a fundamental point that both sides should be able to agree on. An interviewer asked him:
"Q. We are expecting to see animals in trouble here, struggling with radiation poisoning and mutations. How is it that nothing seems to be wrong?

A. In the first few years after the accident, when high concentrations of various radionuclides dotted the land, there were, in fact, many casualties. In the wild, any sick animal will soon disappear. Twenty-five years down the road, much of the fall-out has been diluted by water or sand, washed away or blown away by the wind. The ambient radiation is not very high, although dirty spots with Plutonium in the ground remain and will remain for a long time. According to a very elaborate study by Belarusian scientists, 4 to 6 % of every new generation of small rodents suffers some sort damage from radiation. These individuals will usually not reproduce. If they do, they do not seem to pass on radiation-induced changes to the next generation. The overall population is not affected by a loss of 4 to 6 % per generation.
Q. Would we be more affected by radiation than the animals here? Why are people not allowed to return to the zone?
A. Simply because 4 to 6% of all babies being in some way handicapped would be a disaster for humans, even though a human population as a whole would continue to live."

So, while anti-nuclear activists could concede the point here that some animals appear to be thriving, by a revised definition of the word thriving, pro-nuclear activists have to admit that the finding means little to humans. The question is not whether a location is fit of habitation, or whether the local radiation is going to give me cancer, but whether it is fit for human procreation. The anti-nuclear side can admit that most adults can indeed tolerate fairly high levels of radiation, but the pro-nuclear side has to admit that fetuses and children can be severely damaged by very low levels of radiation. This is why the CEZ will remain uninhabited, and why people in Fukushima are justified in wanting compensation to leave the area. Despite government expenditures to prop up the economy of contaminated areas, these areas are probably doomed. The market will speak. No one will want to raise children in such areas, and it is impossible to imagine any revitalization plan that can succeed in the absence of young people.

In April, 2011, Wired Magazine covered the controversy over wildlife studies in the CEZ, discussing the conflicting research findings on whether wildlife really was recovering. The article was more supportive of the view that the bad effects have been exaggerated, but it mentioned one grim qualification that should give pause to the optimists who think this land is going to recover:

"While iodine-131 decayed long ago and the strontium and cesium are slowly becoming less potentially lethal, the hot particles of plutonium-241 scattered across the landscape are actually decaying into an even more toxic isotope, americium-241. A more powerful emitter of alpha radiation than plutonium, americium is also more soluble and can easily find its way into the food chain. Americium-241, in turn, decays into neptunium-237, another energetic alpha emitter that has a half-life of more than 2 million years. As of yet, the long-term effect of americium-241 on animals remains largely unknown."

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