PURITY ANALYSIS OF SOME MARKETED BRANDS OF ORGANOPHOSPHORUS PESTICIDES AVAILABLE IN BANGLADESH

Abstract

The study was conducted to determine the purity of available marketed brands of five (5) selected organophosphorus pesticides viz., Diazinon, Quinalphos, Malathion, Chlorpyrifos and Dimethoate. A total of forty one (41) samples were collected from different locations of Dhaka district during September’2019 to April 2020. The samples were carried to the Pesticide Analytical Laboratory, Pesticide Research & Environmental Toxicology Section, Entomology Division of Bangladesh Agricultural Research Institute (BARI), Gazipur. The collected samples were analyzed using Gas Chromatography (GC) coupled to Flame Ionization Detector (FID) and Electron Capture Detector (ECD). Among 41 different brands of organophosphorus pesticide samples, 22 (53.65%) were found 100% pure in terms of active ingredient (AI). Whereas 19.51% of the total tested brands were 80-100% pure, and the remaining 26.83% were below 80% pure, of which about 13% pesticide brands contained less than 50% AI. This means that farmers are using pesticides having less amount of AI than required. This study reflects the too much expectation with these 41 samples of the presence of AI in different marketed brands of organophosphorus pesticides in Bangladesh which will help the farmers to be aware of their application for crop protection informed by DAE. It appears that some pesticide groups have more purity compare to others. For example, Chlorpyrifos and Quinalphos grouppesticides. To ensure 100% AI in different marketed brands of pesticides, regulatory mechanism should be strengthened.