Optimization of GC-MS/MS for the Determination of Dioxins and PCBs in Feed and Food and Comparison of Results with GC-HRMS

Abstract

Until recently, the analysis of dioxins and dioxin-like PCBs in feed and food was generally performed by gas chromatography coupled to high resolution mass spectrometry (GC-HRMS) due to its superior resolution and sensitivity compared to the then available gas chromatographic techniques with other detectors. However, in the past few years the technology of GC coupled to tandem mass spectrometry (GC-MS/MS) has made great progress and modern GC-MS/MS systems nowadays reach similar limits of detection as GC-HRMS systems. This paper describes the step-wise optimization of GC-MS/MS variables for the sensitive and selective measurement of dioxins and PCBs in feed and food to comply with the performance criteria set by the EU Commission for confirmatory methods. The developed method was shown to give linear response over the required concentration range and good repeatability. Analyses of samples from official feed and food control demonstrated that a surveillance of the legal limits for dioxins and PCBs in feed and food is easily achievable. The generated quantitative results for dioxins and PCBs are compared with those data obtained for the same samples by GC-HRMS and show good agreement. As the purchase and running costs for GC-MS/MS systems constitute only a fractional amount compared to GC-HRMS instruments, the application of GC-MS/MS represents a cost-effective alternative for GC-HRMS to reliably and unequivocally confirm low levels of dioxins and PCBs in feed and food.