Optimization of large volume injection for determination of organophosphorus flame retardants in river water by GC-MS

Contamination of surface water by organophosphorus flame retardants (OPFRs) is of concern due their persistency and toxic properties. The main sources of OPFRs to the aquatic environment are industrial and domestic effluents since these substances are not efficiently removed in wastewater treatment plants. Analytical methods for determination of OPFRs at trace concentrations in river water are necessary for monitoring studies that aim to evaluate the risks to the aquatic environment. In this study, an analytical method was developed for determination of ten OPFRs in river water extracts by large volume injection and gas chromatography coupled to mass spectrometry. The conditions of the programmed temperature vaporization injector were optimized using a multivariate experimental design. Two full factorial experiments were performed in order to optimize the solvent evaporation and the transferring of the analytes to the chromatographic column. Among the factors evaluated only the gas purge flow and the purge time were significant on the instrumental response. These factors were further optimized using a central composite experiment. The optimized conditions were presented at Table 1. The developed method allowed the determination of all the OPFRs in river water extracts at levels of environmental relevance.