Kinetics and mechanism of amitraz hydrolysis in aqueous media by HPLC and GC-MS

Degradation processes of amitraz in aqueous media have been studied by spec trophotometry, HPLC and GC-MS. Amitraz undergoes hydrolysis reactions at an y pH, but towards the acidic pH range hydrolysis proceeds at a faster rate. Depending on the pH value, different products of the hydrolysis have been identified. The main degradation products are 2,4-dimethylaniline at very a cidic pH values (pH < 3), N-(2,4-dimethylphenyl)-N'-methylformamidine and 2 ,4-dimethylphenylformamide at less acidic media (pH 3-6) and 2,4-dimethylph enylformamide at basic pH. The mechanisms of the different hydrolysis proce sses have been elucidated. (C) 1999 Elsevier Science B.V. All rights reserv ed.