<img class="styles__noscript__2rw2y" src="https://s.w-x.co/util/image/w/glacier_13.jpg?v=at&w=485&h=273" srcset="https://s.w-x.co/util/image/w/glacier_13.jpg?v=at&w=485&h=273 400w, https://s.w-x.co/util/image/w/glacier_13.jpg?v=ap&w=980&h=551 800w" > Glaciers in the Qalerallit Imaa Fjord in southern greenland. America. The dark layer is cryoconite, which absorbs radioactive fallout at high levels. (REDA&amp;CO/Contributor/Getty Images)

At a Glance Researchers say levels of radioactive fallout is 10 times higher in glaciers.

The fallout comes from nuclear accidents and weapons testing.

As if there isn't enough to worry about with glaciers melting and releasing trapped greenhouse gases and long-dead viruses, now it turns out the world's glaciers are storing tons of radioactive nuclear fallout that could prove troublesome as they continue to melt.

A recent survey by an international team of scientists found that all 17 glaciers the team studied around the world had elevated levels of fallout radionuclides (FRNs), adioactive atoms that come from nuclear accidents in places like Chernobyl and Fukushima and weapons testing from the 1950s and 1960s, according to the research presented last week in Vienna, Austria, at the European Geosciences Union conference.

The study looked at the presence of fallout radioactive material in the dark layer of ice sediments on glaciers, or cryoconite, and determined the levels were 10 times higher than those detected in non-glaciated environments, suggesting the ice absorbs the radioactive material.

“They are some of the highest levels you see in the environment outside nuclear exclusion zones ," study researcher Caroline Clason, a University of Plymouth lecturer in physical geography, told Agence France-Presse on Wednesday.

Radioactive material, when released into the atmosphere, falls back to earth as acid rain. It's then absorbed by plants and soil. When it falls onto glaciers in the form of snow, it is absorbed by the heavier cryoconite and the concentrations are much higher.

The researchers noted that FRNs were not necessarily more concentrated in glaciers nearest sites of nuclear fallout like Chernobyl, which highlights that the "global reach of nuclear events and other atmospherically-transported contaminants."

"Radioactive particles are very light so when they are taken up into the atmosphere they can be transported a very long way," Clason told AFP. "When it falls as rain, like after Chernobyl, it washes away and it's sort of a one-off event. But as snow, it stays in the ice for decades and as it melts in response to the climate it's then washed downstream."

Clason told Live Science the immediate threat to humans is minimal. The fear is that these contaminants may eventually seep into the environment through meltwater into rivers and lakes and eventually into the food chain.

Americium, which is produced when Plutonium decays, is "particularly dangerous" because it lasts 400 years, Clason told AFP.

"Americium is more soluble in the environment and it is a stronger alpha (radiation) emitter. Both of those things are bad in terms of uptake into the food chain," Clason said.

Clason noted in a press release that continued research in understanding how FRNs may impact the food chain and human health is vital because "it is clearly important for the pro-glacial environment and downstream communities to understand any unseen threats they might face in the future.”