By Sid Perkins
From San Francisco, at the 2001 fall meeting of the American Geophysical Union
A new study of dust lofted to Antarctica suggests that significant amounts of trace metals coated dust grains long before industries began loading the atmosphere with such pollutants.
Blowing dust in the American Southwest often carries large amounts of lead, cadmium, and arsenic. Yet those elements are minor constituents of Earth’s crust, says Todd K. Hinkley, a geochemist with the U.S. Geological Survey in Denver. Some of these tainted dusts can be traced back to specific, polluted sources, such as California’s Owens Lake (SN: 10/6/01, p. 218: Ill Winds), but the origins of others can’t be pinned down.