July 23, 2002
AMES, Iowa — Joel Coats, professor of entomology at Iowa State University, and a team of graduate students are developing safer, cheaper ways to find and clean-up agricultural chemical spills.
Researchers are looking at the use of "biological endpoints" as environmental markers of chemical spills. Biological endpoints identify chemicals that could be potentially harmful to biological systems. They associate how specific chemicals relate to biological activity.
"We feel that we have found biological endpoints that are more relevant to living systems than the standard chemical tests of pesticide residues in soils," Coats said.
Biological endpoints include, for example, methods of testing for toxicity levels in soils and testing earthworms for the accumulation of pollutants. Graduate student Jason Belden has developed several biological endpoints and is comparing their utility and relevance to traditional chemical residue analysis.
Coats said the biological tests are used to determine how much pesticide is available to plants and animals. This provides a measurement of potential contact to humans through direct contact with contaminated soil (walking, digging, or breathing dust from a contaminated site), or indirect exposure to pesticide residues through the food-chain (consuming animals or plants that accumulated pesticides from a site).
"Our main goal is to find out if the biological endpoints give a different picture of the safety or hazard of contaminated soil from the traditional chemical analysis of the contaminated soil," Coats said. "If the evaluation is different, we hope to assess which is more valuable and cost-effective."
Coats said phytoremediation (using plants to biodegrade or soak up pollutants in soil), one of the endpoint techniques they have been working with, shows promise.
"We believe our work on phytoremediation of contaminated soils will be valuable in cleaning up contaminated sites with an economical, slow-but-sure, in-place method that will be much more aesthetically and financially appealing to the owners and state agencies," Coats said.
The Center for Health Effects of Environmental Contaminants at the University of Iowa provided a grant of $20,000 for the research.