Nontarget deposition and losses of oxamyl in surface runoff from flatwoods citrus production areas.
Pesticide export from citrus production areas is a concern in the Indian River Lagoon drainage basin (Florida, USA). These studies evaluated nontarget deposition and losses of the insecticide oxamyl from typical flatwoods citrus production areas in South Florida. Deposition was estimated with the use of Teflon spray targets placed across nontarget water furrows during spray applications. After oxamyl applications, surface water runoff events were generated with an overhead irrigation system to simulate relatively low intensity rainfall. Results indicated that 0.3 to 20.0% of the applied active ingredient landed on nontarget water furrow surfaces and that the majority of oxamyl loss occurs in runoff events shortly following application. Mean concentrations were greater during the first runoff events, ranging from 34.7 to 47.0 microg/L. Total losses during the first several hours of each set of runoff events ranged from 0.1 to 3.8% of the total active ingredient applied. Similar losses can be expected when rainfall occurs shortly after application for other pesticides with similar chemical properties and application methods.
Wilson
Patrick Chris
PC
University of Florida/Institute of Food and Agricultural Sciences-Indian River Research and Education Center, Soil and Water Science Department, 2199 South Rock Road, Fort Pierce, Florida 34945, USA. pcwilson@mail.ifas.ufl.edu
Boman
Brian
B
Foos
Jane Ferguson
JF
D002219:Carbamates / Q000737:chemistry*; D002957:Citrus; D010575:Pesticides / Q000737:chemistry*; D014874:Water Pollutants, Chemical
D002219:Carbamates; D010575:Pesticides; D014874:Water Pollutants, Chemical; C011960:oxamyl