Evaporation drift of pesticides active ingredients.
Losses of pesticide active ingredients (a.i.) into the atmosphere can occur through several pathways. A main pathway is evaporation drift. The evaporation process of pesticide a.i., after application, is affected by three main factors: Physicochemical properties of the pesticide a.i., weather conditions and crop structure. The main physicochemical parameters are the Henry coefficient, which is a measure for the volatilization tendency of the pesticide a.i. from a dilute aqueous solution, and the vapour pressure, which is a measure for the volatilization tendency of the pesticide a.i. from the solid phase. Five pesticide a.i., with various Henry coefficients and various vapour pressures, were selected to conduct laboratory experiments: metalaxyl-m, dichlorovos, diazinon, Lindane and trifluralin. Evaporation experiments were conducted in a volatilization chamber. It was found that the evaporation tendencies significantly differed according to the physicochemical properties of the a.i.
De Schampheleire
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Ghent University, Laboratory of Crop Protection Chemistry Coupure links 653, BE-9000 Gent, Belgium.
Nuyttens
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De Keyser
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Spanoghe
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D000393:Air Pollutants / Q000032:analysis*; D018556:Crops, Agricultural / Q000737:chemistry*; D004784:Environmental Monitoring / Q000379:methods*; D008956:Models, Chemical; D010573:Pesticide Residues / Q000032:analysis; D010575:Pesticides / Q000032:analysis*; D014835:Volatilization
D000393:Air Pollutants; D010573:Pesticide Residues; D010575:Pesticides