ABSTRACT
A highly selective and sensitive method based on gas chromatography-tandem mass spectrometry (GC-MS/MS) to identify and quantify persistent organochlorine pesticides, (18 compounds including primary compounds and metabolites), in animal internal organs (kidneys, liver, and brain) has been developed. Tandem mass spectrometric conditions were individually optimized for each target compound in Multiple Reaction Monitoring (MRM) mode to obtain maximum sensitivity. Prior to instrumental analysis, a sample preparation method based on matrix solid phase dispersion (MSPD) followed by acidic digestion with sulfuric acid to reduce matrix co-extractives was employed. Analyses of real samples were carried out on coypus (Myocastor coypus) from the autumn slaughter of 19 animals. In the analyzed samples, three of the target compounds, namely DDE-pp' (DDT metabolite), HCB and lindane, were detected. Their concentration levels fell in the ranges of 0.003-0.007, 0.003-0.025, and 0.003-0.021 mg kg(-1) (0.005, 0.010, and 0.010 mg kg(-1) on average) in the case of DDE-pp', HCB and lindane, respectively. Although low quantities of organochlorine pesticides do not pose an immediate danger to consumers' health, they should be of public health concern considering long-term, low-dose exposure.