Most residents of the parched southwestern United States accept dust as an unavoidable fact of desert life. The silty powder that settles from the air on to desktops, beneath beds, and into noses is viewed by many as nothing worse than a common annoyance. But, in recent years, dust has gone from being a benign nuisance to major health hazard, as scientists have discovered harmful chemicals and microorganisms hitching a ride on the airborne particles.
Storms in places as distant as China and Africa have generated public attention with dust clouds that travel across oceans to North America, bringing with them living bacteria, fungi, heavy metals, and other pollutants.
Researchers at Arizona State University now say that dust generated in our own back yards could be equally dangerous. Dust blowing from local industries and agricultural fields has the potential to carry cancer-causing pesticides and toxic heavy metals, says ASU geologist William Stefanov. Though the fine dirt that settles into homes across the Phoenix area may look harmless, chronic inhalation of contaminated dust could lead to increased risk for cancer or heavy metal poisoning, leaving Arizona residents to wonder: Do you know where your dust has been?
In collaboration with ASU geology Professor Philip Christensen and University of Pittsburgh geologist Mike Ramsey, Stefanov is using images taken from space to map the movement of dust in Arizona. The maps can then be used to determine areas where health risks are most likely, and where scientists should do additional monitoring. He will present the first results of this project at the spring meeting of the American Geophysical Union in Boston on May 30, 2001.
Stefanov uses images taken by Landsat 7, a satellite operated jointly by NASA and the United States Geological Survey, to identify the areas where winds are most likely to pick up dust, carry it through the air, and eventually drop it off. From the Landsat 7 pictures, Ste
Contact: James Hathaway
Arizona State University