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Pesticide Trends in Major Rivers of the United States, 1992–2010

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Pesticide Trends in Major Rivers of the United States, 1992–2010 National Water-Quality Assessment Program Pesticide Trends in Major Rivers of the United States, 1992–2010 Scientific Investigations Report 2014–5135 U.S. Department of the Interior U.S. Geological Survey Cover. View of Missouri River from Double Ditch Indian Village Historic Site, north of Bismarck, North Dakota, September 26, 2006 (photograph by Kathleen Macek-Rowland). Pesticide Trends in Major Rivers of the United States, 1992–2010 By Karen R. Ryberg, Aldo V. Vecchia, Robert J. Gilliom, and Jeffrey D. Martin National Water-Quality Assessment Program Scientific Investigations Report 2014–5135 U.S. Department of the Interior U.S. Geological Survey U.S. Department of the Interior SALLY JEWELL, Secretary U.S. Geological Survey Suzette M. Kimball, Acting Director U.S. Geological Survey, Reston, Virginia: 2014 For more information on the USGS—the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment, visit http://www.usgs.gov or call 1–888–ASK–USGS. For an overview of USGS information products, including maps, imagery, and publications, visit http://www.usgs.gov/pubprod To order this and other USGS information products, visit http://store.usgs.gov Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Although this information product, for the most part, is in the public domain, it also may contain copyrighted materials as noted in the text. Permission to reproduce copyrighted items must be secured from the copyright owner. Suggested citation: Ryberg, K.R., Vecchia, A.V., Gilliom, R.J., and Martin, J.D., 2014, Pesticide trends in major rivers of the United States, 1992–2010: U.S. Geological Survey Scientific Investigations Report 2014–5135, 63 p., http;//dx.doi.org/10.3133/ sir20145135. ISSN 2328-0328 (online) iii Contents Conversion Factors .......................................................................................................................................vi Abstract ...........................................................................................................................................................1 Introduction.....................................................................................................................................................1 Purpose and Scope ..............................................................................................................................2 Study Design and Methods ..........................................................................................................................3 Site Selection.........................................................................................................................................3 Sample Collection, Processing, and Field Quality-Control Program ............................................7 Analytical Methods for Pesticides .....................................................................................................7 Sources and Preparation of Concentration Data for Trend Analysis...........................................7 Sources and Preparation of Agricultural-use Intensity Data for Trend Analysis ......................8 Selection of Pesticides and Periods for Trend Analysis ................................................................8 Statistical Method for Analyzing Trends in Pesticide Concentrations ......................................12 Statistical Method for Analyzing Trends in Agricultural Use ......................................................13 Use and Properties of Pesticides ..............................................................................................................13 Trend Results ................................................................................................................................................14 National Analysis of Independent Trend Sites ........................................................................................22 Herbicides ............................................................................................................................................23 Simazine ......................................................................................................................................23 Prometon .....................................................................................................................................23 Cyanazine ....................................................................................................................................23 Metolachlor.................................................................................................................................25 Atrazine and Deethylatrazine ..................................................................................................28 Alachlor .......................................................................................................................................28 Tebuthiuron .................................................................................................................................28 Dacthal.........................................................................................................................................31 Pendimethalin .............................................................................................................................31 Insecticides..........................................................................................................................................31 Chlorpyrifos .................................................................................................................................31 Malathion ....................................................................................................................................31 Diazinon .......................................................................................................................................36 Fipronil and Desulfinylfipronil ..................................................................................................36 Carbofuran ..................................................................................................................................36 Carbaryl .......................................................................................................................................36 Nested Basin Analysis for the Mississippi River Basin ........................................................................42 Simazine ...............................................................................................................................................42 Metolachlor .........................................................................................................................................44 Atrazine and Deethylatrazine ...........................................................................................................46 Diazinon ................................................................................................................................................49 Conclusions...................................................................................................................................................49 Acknowledgments ..............................................................................................................................51 References Cited..........................................................................................................................................51 Appendix 1. Preparation of Concentration Data for Trend Analysis ..................................................58 Appendix 2. Examples of Agricultural-Use Intensity Data and Interval Censored Trend Analysis .................................................................................................................................60 iv Figures 1. Graph showing estimated agricultural pesticide use in the conterminous United States, 1992–2010 .............................................................................................................2 2. Map showing sampling sites (table1) used for analysis of pesticide concentration trends in major rivers, 1992–2010 ...............................................................................................3 3. Graphs showing total conterminous U.S. agricultural use for herbicides and insecticides by year and crop, 1992–2010 ..............................................................................15 4. Maps showing simazine concentration and agricultural-use trends at independent trend sites, 1992–2010 ................................................................................................................24 5. Maps showing prometon concentration trends at independent trend sites, 1992–2010 .....................................................................................................................................25 6. Maps showing cyanazine concentration and agricultural-use trends at independent trend sites, 1992–2010 .........................................................................................26 7. Maps showing metolachlor concentration and agricultural-use trends at independent trend sites, 1992–2010 .........................................................................................27 8. Maps showing atrazine and deethylatrazine concentration trends
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