Submitted to: American Chemical Society Symposium Series
Publication Type: Abstract Only
Publication Acceptance Date: 3/1/1998
Publication Date: N/A
Citation: Interpretive Summary:
Technical Abstract: The study objective was to conduct a small scale synoptic survey of representative water resources draining agricultural land on which these chemicals might be used for occurrence of residues. These relatively new families of herbicides are used mostly in conservation tillage systems to control grasses in corn and soybean fields where they are generally applied post-emergence. Water samples were collected from 54 midwestern locations during the summer of 1997, and analyzed for residues of 15 sulfonylurea and imidazolinone chemicals, and one sulfonamide. Each site was sampled between mid-June and early-August with several stream sites sampled twice. The method, developed jointly by the chemical manufacturer's and the USEPA, provides a 100 ng/L limit of quantitation in surface water for all analytes. Both nicosulfuron and imazethapyr were detected in one Iowa stream and flumetsulam in a Louisiana stream. None of the groundwater samples yielded detects for any of the analytes.