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.
Description:
A Thesis
Submitted to the Department of Agricultural Chemistry
Sher-e-Bangla Agricultural University, Dhaka
In partial fulfilment of the requirements
for the degree of
MASTER OF SCIENCE (MS)
IN
AGRICULTURAL CHEMISTRY