GC-MS/SIM ANALYTICAL METHOD FOR DETERMINATION OF PENDIMETHALIN RESIDUE IN TOBACCO MATRIX

Abstract

Pendimethalin, a dinitroanilin group pesticide, is being widely used as herbicide in tobacco cultivation. However, apprehensions related to accumulation of residues of crop protection agents (CPAs) at toxic levels in the final produce drives the safety regulations to become more and more stringent in most of the countries. This necessitates continuos monitoring of CPA residues in final produce by employing standard analytical methods. Development of an analytical method for determination of pendimethalin residue important for monitoring pendimethalin accumulation in tobacco leaf. We proposed a new GC-MS/SIM analytical method for extraction and analysis of pendimethalin residue in tobacco leaf matrix. The new method with good linearity (R2>0.99) over the concentration range of 0.015-0.250 mg kg-1 had limit of determination (LOD) and limit of quantification (LOQ) values of 0.004 and 0.01 mg kg-1, respectively. The method with 84-108% recovery showed compliance with international specification. The GCMS/SIM analytical method, based on quantifierqualifier ions (252, 253 & 281) ratio method, had been successfully employed to estimate the pendimethalin residues in some field samples. Results showed that in the majority of field samples, pesticide residue levels were below the GRL value set by CORESTA.