Phenyl Hydrazine Hydrochloride - A New Spray Reagent for Synthetic Pyrethroids

Phenyl hydrazine hydrochloride has been reported as a new spray reagent for the detection of synthetic pyrethroids containing an a-cyano group e.g. fenvalerate, cypermethrin and fenpropathrin The pyrethroids, on alkaline hydrolysis, yield cyanohydrin derivatives which give HCN and corresponding aldehyde. The liberated aldehyde forms coloured complex with phenyl hydrazine hydrochloride reagent. The organochlorine, organophosphorous and carbamates do not interfere in the determination. The limit of detection is about 20 μg. Recoveries from vegetable and water samples ranged from 85–92%.