Effect of pH on the Persistence of Napropamide in Water under Laboratory Simulated Condition

The persistence of napropamide has been studied in water at three different pH (4.0, 7.0 and 9.2) with two doses, ie 0.08 µg mL⁻¹ (T₁) and 0.16 µg mL⁻¹ (T₂) under laboratory simulated condition. The water samples were collected at regular intervals and analyzed following the standard methodology. The dissipation rate followed the first order kinetics in all doses. The persistence of napropamide was higher in acidic solution of pH 4.0 (half-life, 66.2 d) followed by neutral solution of pH 7.0 (half life, 55.8 d) and alkaline solution of pH 9.2 (half life, 56.3 d).The result indicated that the persistence was higher in acidic solution than neutral and alkaline solution irrespective of any treatment doses.