4,000 Miles Apart, Chilean Arsenic Found in Antarctic Ice

Ecologically speaking, at least, the actions that humans have taken on the environment have always seemed to come up to affect us later. The newest study is no exception. Scientists have discovered that the Antarctic ice contains arsenic from Chile.

The study, to be published in Atmospheric Environment, describes how the scientists from Brazil's Polar and Climate Center found traces of arsenic when they were in Antarctica. Within the layers of the ice there, 4,000 miles away, they could trace the rise of Chile's copper industry.

In Antarctica, the scientists took cores samples in the ice and analyzed the amount of arsenic in each layer. Within the samples, the layers of ice gave a small glimpse of the state of the atmosphere from 1883 to 2008. Before 1900, arsenic levels were low, about 1.92 pictograms per gram, but when the Chilean copper industry came into prominence around the 1940s, the levels spiked higher, eventually reaching 7.94 picograms per gram by the 1950s.

In the 1990s the Chilean government started restricting the release of arsenic with environmental laws. These new laws worked, and the arsenic levels in the ice dropped back to the low levels of the pre-1900s. As Popular Science has noted, the World Health Organization has set the safe limit for arsenic in drinking water to be at 10 micrograms per liter so the higher levels in the ice from the 1950s would be considered under these limits.  

Even though the current levels are not enough to greatly affect the Antarctic ecosystem, it does mean that, between Antarctica and Chile, the people and animals lying under the path of the arsenic may have been exposed to larger quantities of the toxic element. As lead author of the study, geologist Franciele Schwanck said, "Prolonged exposure to arsenic can cause various cancers and chronic diseases, and the discovery of low concentrations in Antarctica probably means there are higher concentrations in Chile."

Arsenic is extracted from copper ore during the mining process. Found with the copper, the toxic element is removed through the use of chemicals or smelting. Eventually the arsenic is released into the atmosphere, over the course of the heating and cooling process, where the element combines with the air and falls back to Earth as precipitation. In this case the arsenic was in the rain that fell over the Antarctic.

Phys.org reported that this isn't the first time a poisonous substance has been found in the ice in Antarctica. Scientists have found lead and uranium previously.

Chile is the world's largest copper producer, mining almost one-third of the world's copper. This study may indicate that despite the environmental regulations the Chilean government has put in place, the damage during those decades prior may have already caused damage to their citizens.