HR: 0800h
AN: H31D-1339    [Abstracts]
TI: The Occurrence of Chlorothalonil, its Transformation Products, and Selected Other Pesticides in Texas and Oklahoma Streams, 2003-2004
AU: * Battaglin, W A
EM: wbattagl@usgs.gov
AF: U.S. Geological Survey, Box 25046, MS 415, Denver Federal Center, Lakewood, CO 80225 United States
AU: Kuivila, K M
EM: kkuivila@usgs.gov
AF: U.S. Geological Survey, Placer Hall 6000 J Street, Sacramento, CA 95819 United States
AU: Winton, K T
EM: kwinton@usgs.gov
AF: U.S. Geological Survey, 202 NW 66th Street, Oklahoma City, OK 73116 United States
AU: Meyer, M T
EM: mmeyer@usgs.gov
AF: U.S. Geological Survey, 4821 Quail Crest Place, Lawrence, KS 66049 United States
AB: The purpose of this study is to determine if the fungicide chlorothalonil (2,4,5,6-tetrachloro-isophthalonitrile) or three of its transformation products are transported to surface water after use on peanuts or other crops. Chlorothalonil is classified as a probable carcinogen, and the 4-hydroxy of chlorothalonil transformation product is more soluble, stable, and toxic than its parent compound. In 2003, 14 water samples were collected from three sites in Texas and two sites in Oklahoma. In 2004, six samples were collected from the two Oklahoma sites. Chlorothalonil was not detected in any sample. The 4-hydroxy of chlorothalonil transformation product was detected in three of the six samples collected in 2004, with a maximum concentration of 0.018 μg/L; the other two transformation products were not detected in any sample. In addtion, samples were analyzed for as many as 109 other pesticides and transformation products. Atrazine was detected in 13 of the 19 samples with a maximum concentration of 0.122 μg/L. Deethyatrazine was detected in 10 of the 19 samples with a maximum concentration of 0.04 μg/L. Metolachlor was detected in 8 of the 19 samples with a maximum concentration of 0.019 μg/L. Fifteen other pesticides or pesticide transformation products including 2,4-D, carbaryl, simazine, oryzalin, prometon, tebuthiuron were detected in four or fewer samples. In general, concentrations of pesticides were less than is commonly observed in Midwestern streams.
DE: 1803 Anthropogenic effects (4802, 4902)
DE: 1834 Human impacts
DE: 1871 Surface water quality
SC: Hydrology [H]
MN: Fall Meeting 2005