Twenty five years after the explosion and fire at the Chernobyl nuclear power plant, a United Nations report estimates the disaster caused thyroid cancer in more than 6,000 children in the affected area.
The world's worst nuclear accident caused thousands of cases of thyroid cancer among children, largely from drinking contaminated milk, according to a report by the U.N. Scientific Committee on the Effects of Atomic Radiation.
University of New Mexico Radiology Professor Fred Mettler contributed to the report.
"In our report we say 6,800," said Mettler. "But now, from what I understand people from Belarus say it is 7,000. Now the question they are asking is: what percent of them are due to the accident? And the answer is, most of them."
Dr. Mettler said most of these cases were preventable. He says authorities should have banned milk consumption and distributed potassium-iodine pills, but even so distrust of the authorities was high after the accident.
“When I was in all those villages for those two years, I asked all these people about it, and many of them said, "Yes, we were given pills, but we really did not trust the government. I mean if they couldn’t run a reactor, why should we take these pills that we don’t understand?” he said.
The report said despite the high rate of cancer, only 15 fatalities have resulted.
The nuclear accident took place on April 26, 1986, a time when the Soviet Union controlled the region. Soviet authorities decided not to cancel May 1 outdoor parades in the region, leading more people to be unnecessarily exposed.
With the Chernobyl anniversary approaching, debate over the disaster is expected to take place in the affected region - now the independent nations of Belarus, Russia and Ukraine.
Controversy may swirl around the report's statement that there is no consistent evidence of radiation impact on the health of thousands of emergency workers who came to Chernobyl.
University of Paris researcher Anders Moller has researched the Chernobyl area since it opened to the West after the 1991 fall of communism. He has maintained close contact with family members of the men and women who put out the nuclear fire, and encased the plant in cement.
"That group contains many thousands of people and the most recent estimate I have heard from this group is that hardly any of those are alive today," said Moller.
In the months after the disaster, Soviet authorities relocated about one-quarter-million people from the affected zone. The United Nations report says "these people need not live in fear of serious health consequences."
Report researchers say it is hard to isolate Chernobyl's contribution to higher mortality rates in the region. The nuclear accident undoubtedly contributed to increased rates of depression and alcoholism. But overall mortality rates in the three nations increased in the 1990s.
The collapse of the Soviet Union led to the collapse of the economic system and of the health-care system.
Dr. Mettler said it is very hard to quantify:
"This population group who were saying, 'Oh, well I have been exposed, so it does not make any difference if I take drugs, or drink alcohol or do other risky things,'" he said.
Moller decided to discount the human social factors and to focus on studying animals and birds around Chernobyl.
"On average, they have a reduction in brain size of five percent, compared to normal birds," he said.
From five to 10 percent of birds and other animals near Chernobyl suffered from physical abnormalities, but he says elsewhere in the wild this rate is "virtually nil."
As the 25th anniversary nears, an international drive is underway to raise money to seal the Chernobyl site in a $2-billion concrete shell. This 23-story-high shell will be built on rails and slid over the decaying nuclear power plant and would be the world's largest moveable structure.