HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Figures Only Full Text Free Full Text (PDF) Free Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (3) Citing Articles via Google Scholar Google Scholar Articles by Meyer, M. T. Articles by Goolsby, D. A. Search for Related Content PubMed PubMed Citation Articles by Meyer, M. T. Articles by Goolsby, D. A. Agricola Articles by Meyer, M. T. Articles by Goolsby, D. A. Related Collections Water Quality Agricultural Pesticides Surface Water Quality Water Pollution

TECHNICAL REPORT
Surface Water Quality

Differentiating Nonpoint Sources of Deisopropylatrazine in Surface Water Using Discrimination Diagrams

^a U.S. Geological Survey, 4500 SW 40th Ave., Ocala, FL 34474
^b U.S. Geological Survey, 4821 Quail Crest Place, Lawrence, KS 66049
^c U.S. Geological Survey, Box 25046, Denver Federal Center, MS 406, Denver, CO 80225

* Corresponding author (mmeyer{at}usgs.gov)

Received for publication July 5, 2000. Pesticide degradates account for a significant portion of the pesticide load in surface water. Because pesticides with similar structures may degrade to the same degradate, it is important to distinguish between different sources of parent compounds that have different regulatory and environmental implications. A discrimination diagram, which is a sample plot of chemical data that differentiates between different parent compounds, was used for the first time to distinguish whether sources other than atrazine (6-chloro-N²-ethyl-N⁴-isopropyl-1,3,5-triazine-2,4-diamine) contributed the chlorinated degradate, deisopropylatrazine (DIA; 6-chloro-N-ethyl-1,3,5-triazine-2,4-diamine) to the Iroquois and Delaware Rivers. The concentration ratio of deisopropylatrazine to deethylatrazine [6-chloro-N-(1-methylethyl)-1,3,5-triazine-2,4-diamine], called the D²R, was used to discriminate atrazine as a source of DIA from other parent sources, such as cyanazine (2-[[4-chloro-6-(ethylamino)-1,3,5-triazin-2-yl]amino]-2-methylpropionitrile) and simazine (6-chloro-N,N'-diethyl-1,3,5-triazine-2,4-diamine). The ratio of atrazine to cyanazine (ACR) used in conjunction with the D²R showed that after atrazine, cyanazine was the main contributor of DIA in surface water. The D²R also showed that cyanazine, and to a much lesser extent simazine, contributed a considerable amount (40%) of the DIA that was transported during the flood of the Mississippi River in 1993. The D²R may continue to be a useful discriminator in determining changes in the nonpoint sources of DIA in surface water as cyanazine is currently being removed from the market.

Abbreviations: ACR, concentration ratio of atrazine to cyanazine • DIA, deisopropylatrazine • DEA, deethylatrazine • D²R, concentration ratio of deisopropylatrazine to deethylatrazine • GC–MS, gas chromatography–mass spectrometry

This article has been cited by other articles:

				R. F. Spalding, D. G. Watts, D. D. Snow, D. A. Cassada, M. E. Exner, and J. S. Schepers Herbicide Loading to Shallow Ground Water beneath Nebraska's Management Systems Evaluation Area J. Environ. Qual., January 1, 2003; 32(1): 84 - 91. [Abstract] [Full Text] [PDF]