Simple spectrophotometric method for the determination of carbaryl in soil and insecticide formulations

Abstract

A simple, spectrophotometric method for the determination of carbaryl in soils and insecticide formulations is described. The method is based on the coupling of carbaryl with diazotized 2-aminonaphthalenesulfonic acid in an alkaline medium, to form an azo-dye which has a maximum absorbance at 490 nm, and is extractable into n-butanol. Beer's law is obeyed in the range of 0.01–0.1 ppm of carbaryl. The method suffers no interference from phenol, 1-naphthol and other carbamate insecticides (e.g., propoxur).