Nuclear fires
August 12, 2010Revelations that wildfires have hit hundreds of hectares of land in Russia's western Bryansk region contaminated in the Chernobyl nuclear disaster have raised fears that radioactive material could be released and reach Moscow or even Europe. But radiation experts have said while concern is warranted, any re-release of nuclear contamination would likely pose little risk to human health.
"Every instance of increased radioactivity is a cause for concern, but even for the local population, the levels are going to be relatively low," said Ulrich Abram, a professor in the chemistry department and radiation expert at the Free University of Berlin, in an interview with Deutsche Welle.
"There won't be a resulting cloud of radioactive material that could pose a danger to Europe," he said.
Fears about Russia possibly covering up a new radiation threat were raised when the environmental organization Greenpeace warned that fires in forests contaminated in the 1986 Chernobyl nuclear disaster could trigger radiation pollution. The group accused the Russian government of playing down the threat.
"Fires on these territories will without a doubt lead to an increase in radiation," said Vladimir Chuprov, head of the energy program at Greenpeace Russia, in an interview with The New York Times. "The smoke will spread, and the radioactive traces will spread."
But radiation experts from Russia and other European countries have sought to calm fears, saying that while radioactive isotopes could indeed be released into the air as contaminated material burns, there is no chance that radioactive fallout from the fires could reach anywhere near the magnitude of the Chernobyl disaster.
The concerns come from the fact that large areas of Ukraine, Belarus and Russia are still coated with radioactive residue released when Reactor No. 4 at the Chernobyl nuclear power plan exploded on April 26, 1986.
Two isotopes are of concern
Most of the radioactive isotopes released by the Chernobyl meltdown were caesium-137 and strontium-90, both produced by nuclear fission. Because both are isotopes of metallic elements, they fell to the ground rather quickly, according to Abram, working their way into the soil over the decades since their release and being taken up by plants and trees. When the vegetation burns, the atoms are released.
"Then people could breathe them in, of course," said Abram. "They could be exposed to a higher radiation intensity, which can lead to illness."
Abram remarks that people in the affected areas have been living with Chernobyl's aftermath for decades, although ingesting atoms released by the current fires would expose them at higher levels, and more direct contact.
Internal exposure to caesium-137 and strontium-90, through ingestion or inhalation, allows for the radioactive material to be distributed in the body's soft tissues, especially muscle tissue and bone matter. These tissues are then exposed to the beta particles and gamma radiation of the isotopes, increasing the risk of developing cancer.
Low risk of inhaling nuclear material
Still, Abram says the risk of inhalation is low, because the relative weights of both strontium and caesium send them falling to the ground quickly. Therefore, the risk of breathing the isotopes is low, unless residents are in the immediate vicinity of burning material.
"I don't want to play down the issue, but the overall radiation dosage will not increase significantly for the people who live there," he said.
What he does think a likely outcome will be is that as these isotopes are released, they could travel before falling to the ground again in the presence of high winds. The result would be a larger area of land with low levels of radiation contamination.
Other experts agree with his risk assessment, including Philipp Renaud, head of the environmental radiation laboratory at France's IRSN nuclear safety institute. He said the previous major forest fires in Russia, in 2002, showed that the risk of exposure was minor. Radioactivity in neighboring countries jumped by a thousandth of a becquerel unit and in France, a millionth.
"This isn't dangerous at all," he told the Agence France Presse.
IRSN said that if the contaminated forests burn, local residents would be exposed to about two times the normal radiation levels, which while not ideal, is not a cause for panic.
More dangerous for local residents' health are the non-radioactive toxic fumes caused by the fire, the organization said.
Other nuclear dangers?
Some have been concerned that the fires could reach other nuclear sites in Russia, such as power plants or atomic weapon depots.
But according to Edmund Lengfelder, a director at the German Society for Radiation Protection, the danger of flames engulfing a nuclear reactor and leading to disaster is small.
His group has been active in the Chernobyl region for 20 years and has observed that these days, the Russians are relatively well prepared when it comes to keeping their nuclear facilities out of harm's way.
"Russia is pretty competent when it comes to disaster response and we don't see a particular threat to its nuclear facilities," he said in an interview with Deutsche Welle. "But regarding the material already deposited from Chernobyl, we need to keep an eye on that."
Author: Kyle James
Editor: Cyrus Farivar