HPLC-DAD METHOD FOR DETECTION OF SOME PESTICIDE RESIDUES IN SOIL AND CROPS CULTIVATED IN BANAT COUNTY

Abstract

High productivities and economic benefits in modern agriculture have been accomplished only by the use of pesticides. The introduction of these compounds in the food chain can be considered a risk for human health due to their toxicity. So, pesticides residues and their degradation products resulted by hydrolytic, photochemical and microbial processes in soil and cereals must be monitored and controlled. The aim of this research was to develop rapid and sensitive HPLC-DAD methods for residues detection of several pesticides, imidacloprid, amidosulfuron, bromoxynil and deltamethrin, from soil and some crops, maize, wheat and rape seeds, cultivated in Banat County-Moravita Zone. In order to perform the pesticides extraction, the samples were subjected to an ultrasonic technique, at 59 kHz and 30°C, during 30-45 min., using acetonitrile and acetonitrile-water mixture as solvents. Acetonitrile alone proved to be more appropriate for this purpose. The HPLC analyses were conducted on HPLC-DAD apparatus, Dionex Ultimate 3000 (Dionex Corp., USA), equipped with quaternary pump LPG 3400A, thermostat of columns TCC-3000 and a C-18 Acclaim® 120 Silica-reversed-phase (4.6x150 mm, 5 µm) column, using different compositions of acetonitrile-water as mobile phase. The presented HPLC - Dionex system proved to be very suitable for determination of pesticides residues in soil and crops.