Dry atmospheric deposition and deposition velocities of dicamba, 2,4-dichlorophenoxyacetic acid and γ-1,2,3,4,5,6-hexachlorocyclohexane Original Research Article

This study documents the measurement of atmospheric concentrations and dry deposition rates of three agricultural pesticides currently used in the Canadian prairies: dicamba (2-methoxy-3,6-dichlorobenzoic acid); 2,4-D (2,4-dichlorophenoxyacetic acid); and γ-HCH (γ-1,2,3,4,5,6-hexachlorocyclohexane). Dry atmospheric deposition was measured using a unique new sampler. Deposition velocities were calculated from these data. Dicamba and 2,4-D had, generally higher dry deposition velocities (ranges 0.57–1.50 and 0.29–4.89 cm s−1, respectively) than did γ-HCH (range 0.07–1.0 cm s−1). The possible reasons for this variability are discussed.