Spectrophotometric determination of Malathion(an organo phosphorous insecticide) with Potassium bromate

Abstract

Malathion is an organophosphate insecticide. A simple spectrophotometric method for the
determination of malathion is described. Malathion is decomposed by alkali to dimethyl
dithiophosphate. The formed dimethyl dithiophosphate reacts with potassium bromate in
presence of dilute nitric acid with the formation of orange-yellow color.The absorbance
maximum was observed at 415 nm.The Beers law is obeyed up to 8 ppm for malathion
standard solution. Water and vegetable samples were collected in different areas of
Visakhapatnam district, Andhra Pradesh,India to determine the malathion and found low
levels in the range up to 0.04 ppm.Interference study was carried for other pesticides and ions.