These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.
Pubmed for Handhelds
PUBMED FOR HANDHELDS
Search MEDLINE/PubMed
Title: Major herbicides in ground water: results from the National Water-Quality Assessment. Author: Barbash JE, Thelin GP, Kolpin DW, Gilliom RJ. Journal: J Environ Qual; 2001; 30(3):831-45. PubMed ID: 11401272. Abstract: To improve understanding of the factors affecting pesticide occurrence in ground water, patterns of detection were examined for selected herbicides, based primarily on results from the National Water-Quality Assessment (NAWQA) program. The NAWQA data were derived from 2,227 sites (wells and springs) sampled in 20 major hydrologic basins across the USA from 1993 to 1995. Results are presented for six high-use herbicides--atrazine (2-chloro-4-ethylamino-6-isopropylamino-s-triazine), cyanazine (2-[4-chloro-6-ethylamino-1,3,5triazin-2-yl]amino]-2-methylpropionitrile), simazine (2-chloro-4,6-bis-[ethylamino]-s-triazine), alachlor (2-chloro-N-[2,6-diethylphenyl]-N-[methoxymethyl]acetamide), acetochlor (2-chloro-N-[ethoxymethyl]-N-[2-ethyl-6-methylphenyl]acetamide), and metolachlor (2-chloro-N-[2-ethyl-6-methylphenyl]-N-[2-methoxylethyl]acetamide)--as well as for prometon (2,4-bis[isopropylamino]-6-methoxy-s-triazine), a nonagricultural herbicide detected frequently during the study. Concentrations were <1 microg L(-1) at 98% of the sites with detections, but exceeded drinking-water criteria (for atrazine) at two sites. In urban areas, frequencies of detection (at or above 0.01 microg L(-1)) of atrazine, cyanazine, simazine, alachlor, and metolachlor in shallow ground water were positively correlated with their nonagricultural use nationwide (P < 0.05). Among different agricultural areas, frequencies of detection were positively correlated with nearby agricultural use for atrazine, cyanazine, alachlor, and metolachlor, but not simazine. Multivariate analysis demonstrated that for these five herbicides, frequencies of detection beneath agricultural areas were positively correlated with their agricultural use and persistence in aerobic soil. Acetochlor, an agricultural herbicide first registered in 1994 for use in the USA, was detected in shallow ground water by 1995, consistent with previous field-scale studies indicating that some pesticides may be detected in ground water within 1 yr following application. The NAWQA results agreed closely with those from other multistate studies with similar designs.[Abstract] [Full Text] [Related] [New Search]