Influence of formulation on mobility of metazachlor in soil.

The mobility of metazachlor [2-chloro-N-(pyrazol-1-ylmethyl)acet-2',6'-xylidide] in sand soil and loamy sand soil was studied in a soil column under laboratory conditions. Commercial metazachlor formulation (Metazachlor 500 suspension concentrate (SC)) and metazachlor immobilized in alginate matrix were used for leaching experiment. The initial concentration of metazachlor in soil for both formulations was 2.0 mg mL(-1). After application of herbicide, the columns were irrigated with 100, 40, and 3.7 mm of water. After 1 h, when addition of water was completed, soils were sampled in 5-cm segments and were used for the analysis of residues. The use of alginate controlled release (CR) formulation reduced the vertical mobility of metazachlor into soil layer in comparison with the formulation SC.