Colorimetric determination of carbaryl and its residue in vegetables.

A method has been developed for the determination of carbaryl in formulations and vegetables. Carbaryl on hydrolysis with methanolic KOH gives 1-naphthol which when coupled with diazotised 4:4-diaminodiphenyl sulphone has an absorption max. at 540 nm. Beer's law is obeyed in the range of 0.25-5.0 mug/ml. The method is sensitive and can detect as low as 0.5 p.p.m of carbaryl in cabbage, okra and beans.