Persistent Pb Pollution in Central East Antarctic Snow

Abstract

For decades, well-defined changes in the enrichments and isotopic compositions of Pb have been observed in snow from Dome Fuji and Dome A of the Eastern Antarctic Plateau (EAP). Pb isotope fingerprints have shown a sharp increase in Pb enrichments since the mid-1970s, reaching its peak in 1980, and a large amount of leaded gasoline was used in northern South America, particularly in Brazil. Since then, they have removed much of the Pb additive from Brazil gasoline in the 1980s and have continued to decline in Argentina and Chile in the 1990s, with the removal of much of the Pb additive. After phasing out Pb from gasoline, Cu smelting in Chile has become a major source of Pb, contributing approximately 90% of total Pb emissions in northern South America in the 2005. Nonetheless, as a result of regulatory efforts to curb toxic trace metal emissions in Chile's Cu industry, up until recently, Pb pollution in central EAP has declined substantially. However, more than 90% of the Pb in the farthest places on the planet still have anthropogenic origin, emphasizing the need for the continuation of environmental regulations to reduce Pb emissions.