September 23, 2020

The glaciers hide a radioactive legacy that can be released with the thaw

The glaciers hide a radioactive legacy that can be released with the thaw

The melting of glaciers due to global warming threatens another unforeseen negative effect: the release of potentially dangerous radioactive particles from tests and atomic accidents that were trapped in these snow masses.

This is the main conclusion of a pioneering international research that was presented this Wednesday in Vienna during the annual meeting of the European Union of Geosciences, which is being held this week.

Caroline Clason, from the University of Plymouth (United Kingdom), presented the first results of the tests carried out on 17 glaciers from different places such as the Arctic regions of Sweden, Norway and Greenland, as well as in Antarctica, the Alps, the Caucasus and Canada .

In all the studied glaciers a concentration of nuclear particles was found much higher than usual – sometimes up to ten times higher -, so the ice masses seem to be very efficient in capturing and storing radionuclides.

This pollution comes from nuclear tests and atomic accidents such as the one in 1986 at the Chernobyl power station (then the Soviet Union, now Ukraine) or the most recent one in Fukushima (Japan) in 2011, as well as the old atomic tests of decades ago.

These particles present in the atmosphere – such as the isotopes of lead pb 210, cesium and americium – fall in the form of snow and become trapped inside the ice.

This process of freezing contrasts with that of rain, which drags these particles to the ground, where they are absorbed by the earth and plants, thus diluting their potential danger.

"The concentration of these particles is not a danger in physical contact, but if they are ingested, the danger is that with the thaw it can become part of the food chain," explained Clason to Efe in Vienna.

The scientist stressed that this is an environmental problem that will increase as the glaciers recede due to global warming and these contaminants are released potentially harmful to wildlife and humans.

"In some cases it is about the highest levels that are seen in the environment outside the nuclear exclusion zones," said this British expert on glaciers.

"We do not yet know precisely how harmful this is, we know it is there and that it is a global phenomenon, not something from regions close to Chernobyl, for example," he added.

He explained that perhaps in the future a way to reduce possible risks could be to avoid areas with more pollution, although he stressed that it is necessary to deepen in understanding better the nature of this potential danger.

According to Clason, researchers have detected mostly particles from the Chernobyl accident, since the Fukushima accident in 2011 is still too recent.

The Chernobyl accident, in 1986, is the worst civilian nuclear disaster in history and threw huge radioactive clouds into the atmosphere that produced acid rain in large areas of northern Europe.

The investigation showed that the presence of these particles is not limited to places close to places where there was a nuclear accident, since particles believed to be coming from Chernobyl have been found in very distant places, such as Antarctica.

The researcher recalled that the effect of acid rain is still observed in countries like Sweden, where at some points the meat of wild boar still contains ten times more radioactive cesium (from Chernobyl) than the limit allowed for consumption.

Of the radioactive substances found, the most dangerous is americium because it has a very long life, of more than 400 years, and can be introduced more easily into the food chain.

"It is necessary that we address this problem, it is an environmental process that we must understand," concluded the researcher.

Luis Lidón


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