Butter can be used to measure worldwide air pollution

When professor Kevin Jones goes shopping for laboratory supplies, one of his first stops is the local grocery store, specifically, the dairy section. Jones is one of a team of environmental scientists who have found another use for butter - tracking the spread of air pollution around the world.

Jones, a professor at Lancaster University in Lancaster, England, and his colleagues say that a pat of butter could be an effective monitor for atmospheric pollutants. Their conclusions are reported in the current (March 15) issue of Environmental Science & Technology, a peer-reviewed journal of the American Chemical Society, the world's largest scientific society. Traditional pollution analysis uses specialized air sampling devices that are larger, more expensive and more complicated than butter, according to the researchers.

The researchers see butter primarily as a way to estimate and monitor regional pollution levels. Butter samples then could be collected from different areas to estimate the international distribution of the pollutants, Jones said. Elevated regional pollutant concentrations could help investigators better determine the source of the emissions, he noted. The current findings with butter mirror known worldwide patterns of estimated persistent organic pollutant emissions, according to Jones.

Pollutants carried aloft by the wind eventually fall to Earth, often on pastures where cows graze. Persistent organic pollutants - which include PCBs (polychlorinated biphenyls), dioxins and some pesticides - then accumulate in the cows' milk fat, which makes up approximately 80 percent of butter, according to Jones. Margarine, which has less milk fat, is not as useful, he added.

Although airborne emissions can travel great distances, butter is "an important reflection of contamination levels in a local environment and gives an indication of potenti
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Contact: Beverly Hassell
b_hassell@acs.org
202-872-4065
American Chemical Society
13-Mar-2001