the Determination of diazinon residues in artificially polluted soils.

Abstract

The combination effects of diazinon insecticide (O, O-diethyl O-[6-methyl-2-(1-methylethyl)-4-pyrimidynyl]), three different soil orders (Entisols, Vertisols and Inceptisols) and two soil moisture contents (50% and 100% of field capacity) was studied in a pot experimental design. This experiment last for two months from with five sampling periods at biweekly intervals. The main obtained results of this study were the lowest pH values (6.53±0.006) shown by the combined treatment DS3W2. The combinations DS3W1, DS3W2 and CS1W1 showed the highest organic matter levels (20.698±0.001 g.kg-1). The combined treatment DS3W2 showed the highest total nitrogen contents (2.811±0.003 g.kg-1). Diazinon residues were above the maximum residue limit (MRL) after 24h of application. Whereas, residues have not detected in the treated soils during the other sampling periods and this may indicate complete degradation of diazinon, which may refer to diazinon properties, environmental factors, microbial activities and soil characteristics.