VIENNA Japan's nuclear accident is not expected to have any serious impact on people's health, based on the information available now, the head of a U.N. scientific body said on Wednesday.
Wolfgang Weiss, chairman of the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR), also said the Fukushima disaster was less dramatic than Chernobyl in 1986 but "much more serious" than Three Mile Island in 1979.
"It is in between in terms of environmental effects, not in terms of health impact," Weiss told reporters.
Weiss said the committee planned to look formally into the Fukushima accident and its conseequences, but stressed the emergency was not yet over. He was speaking after Japan on Wednesday stopped highly radioactive water leaking into the sea from the damaged nuclear power plant.
Despite the breakthrough, experts in the country said the damaged reactors were far from being under control almost a month after they were hit by a massive earthquake and tsunami.
Weiss praised Japanese authorities for starting to implement thyroid screening for children and said all measurements so far in this respect were below acceptable levels in the country.
"The only proven effect after Chernobyl was thyroid cancer in children," he said.
Highlighting the differences between Chernobyl and Fukushima, he said people in villages close to the plant in the then Soviet Union were exposed to radioactive iodine that contaminated milk and vegetables.
"They inhaled first, then they ingested this iodine and this caused the problem," Weiss said. "In Fukushima, the people were evacuated before any release took place, so this is a totally different situation."
Asked what health consequences he expected from Fukushima, he said: "From what I know now, nothing, because levels are so low. In food, people are talking about levels which would give you one millisieverts per year, five millisieverts per year ... this is nothing where we would expect major health impacts."
Radiation is measured using the unit sievert, which quantifies the amount absorbed by human tissues.
Weiss said: "We have seen traces of iodine in the air all over the world now but they are much, much, much lower than traces we have seen at similar distances after Chernobyl."
In Chernobyl, hundreds of people received high doses of radioactivity and about 135 got acute radiation sickness, Fred Mettler, another member of UNSCEAR, said.
"We haven't seen any of that at Fukushima so the early management by the Japanese here is very different from what happened at Chernobyl," Mettler said.
(Editing by Louise Ireland)