The Chernobyl nuclear power station in Ukraine has finally been closed, 15 years after the world's worst nuclear disaster. But the fall-out from the 1986 explosion continues to be felt across the region.

Engineers at Chernobyl on Friday initiated the final "rapid emergency defence" procedure by slowly lowering nuclear control rods into the plant's last functioning reactor.

The ceremony, attended by the Ukrainian president, Leonid Kuchma, took place in the shadow of the highly radioactive remains of reactor number four, which lies entombed in a concrete sarcophagus.

The closure heralds the start of a long process of decommissioning for the plant. But the effects of the explosion will continue to be felt long after Chernobyl has ceased to exist.

In Switzerland, and the rest of western Europe, radiation levels have fallen to the point where they no longer pose a threat to humans, according to experts.

In Switzerland, and particularly canton Ticino, the radioactive element, Caesium 137, is still present in the soil and therefore in mushrooms and game. But Felix Blumer of Switzerland's nuclear monitoring alarm centre, is confident that "there is absolutely no risk to the public".

The environmental organisation, Greenpeace Switzerland, is less sure. Spokesman Stefan Füglister says that, based on studies in France, the Alps are likely to contain nuclear "hotspots" where contamination of mushrooms, milk and livestock "could pose a threat to human health".

The problems in western Europe, though, are as nothing compared to the situation in Ukraine and neighbouring Belarus and Russia.

Thousands are thought to have died as a result of radiation-related illnesses in the aftermath of the explosion. Today, an estimated one in 16 Ukrainians, as well as millions of Russians and Belarussians, suffer health disorders, including thyroid cancer and respiratory problems.

The Swiss Development Corporation supports a number of Chernobyl-related projects in Ukraine. Hans Peter Maag of the former Soviet Union section says the problems facing the country are far from over. "There is long term contamination, and very little is known about the effects."

His words are echoed by Igor Kovalchuk, a visiting research scientist from Basel's Friedrich Miescher Institute: "We started with small wild plants and then moved on to more important crops like wheat, oats and barley. We found that the number of genetically mutated plants was six times higher than we had expected."

Kovalchuk and other scientists agree that full implications may not be known for at least another 20 years.

What is clear, though, is devastating effect Chernobyl has had on the lives of millions of people. Dusan Zupka, manager of the United Nations programme on Chernobyl, told swissinfo that "Every area of life is affected - from human health, to the environment, to the economy, to social infrastructure".

The most obvious effect has been on the region's economy. Once known as the "bread basket" of the Soviet Union, the area is now almost destitute because local people cannot find markets for their food and timber.

"Unemployment and economic collapse is another long-term consequence of Chernobyl and another reason why we really cannot afford to neglect this region," says Zupka.

swissinfo

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