Twenty years since Chernobyl and doctors still unsure about true consequences

With the 20th anniversary of the Chernobyl disaster coming up in April many scientists and analysts are still unsure of the true scale of the accident. Up to mid-2005, fewer than 50 deaths had been directly attributed to radiation from the disaster, almost all being highly exposed rescue workers, many of whom died within months of the accident, although others died as late as 2004. But the latest UN report predicts that up to 4000 people could eventually die of radiation exposure and cancer induced as a result of it. Danuta Szafraniec reports.

When the Soviet era Chernobyl reactor blew in 1986 it blasted 200 times the combined radiation of the Hiroshima and Nagasaki atom bombs into the air. The radioactive 'cloud' traveled with the winds across Europe, causing panic across much of the continent. There were some staggering estimates of hundreds of thousands of fatalities. Poland was one of the first countries to react. Just hours after the explosion, stable liquid iodine, preventing radioactive elements from entering into the thyroid glands, was administered in the whole country, including its most affected north-eastern regions. Dr Andrzej Komosa works at the Radiochemistry Department at the Maria Sklodowska University in Lublin, eastern Poland where contamination tests were conducted directly after the explosion on April 26, 1986.

"I remember this date very well because it was the first time I had contact with such a large amount of isotopes. I was a young scientist and we had only small, simple radiometers. We used this apparatus to see the scale of the contamination of the environment, the grass or the atmosphere. Chernobyl contamination was known to reveal hot particles - parts of the reactor core. It contained very large amount of isotopes as a product of fusion and also material like uranium or plutonium. At this time my colleague found on his balcony one such hot particle using this simple measuring device. With the spectrometer we found a very large activity of products of fusion reaction. It came of course directly from the Chernobyl reactor."

Up to mid-2005, fewer than 50 deaths had been directly attributed to radiation from the disaster, almost all being highly exposed rescue workers. But the latest UN report predicts that up to 4,000 people could eventually die of the long-term effects of radiation exposure. It bases the figure on a "linear no-threshold" theory - contradicted by many - which assumes that even low levels of radiation at exposures below those that naturally occur in the environment will lead to quantifiable deaths. Professor Zbigniew Jaworowski, a former chairman of the United Nations Scientific Committee on the Effects of Atomic Radiation sees such data as questionable:

"We know that in fact the medical effects of Chernobyl were caused by extremely high doses suffered by the people working in the nuclear power station and by members of the rescue team. Altogether, due to those extremely high doses, 28 people died after being irradiated. We cannot say that any level of radiation can be dangerous. There is even a level at which radiation is probably beneficial for our health. In the past when life started on this Earth natural radiation was several times higher than it is now because naturally radioactive elements are dying out with time."

In spite of the relatively low number of casualties in the Chernobyl blast, environmental activists argue that no-one can deny it emitted a huge amount of radioactivity into the atmosphere and resulted in a massive disruption of life throughout Europe. Jan Haverkamp, nuclear energy consultant for Greenpeace, says that the statistics are unreliable and contradictory:

"My best guess is that the lower limit on the number of victims is 4000, but even if it is only 4000, that is an enormous number of people for one catastrophe - more than died in the attacks on the Twin Towers. That is the very lowest estimate, based on very limited research on the batch of people which could be followed. The upper estimates rise to 60 000 deaths, which is something almost beyond the imagination."

Speculation over the real impact of Chernobyl continues, but the fact remains that 20 years after the blast there are still "hot spots" in Europe. One is in Lapland where reindeer meat often has to be destroyed because it contains high levels of cesium; another is in Scotland, where in one area sheep can still not be bred for meat. There may be many more, as these hot spots are still difficult to trace.