Sorbent-packed needle microextraction trap for synthetic musks determination in wastewater samples

A needle trap (NT) device filled with HF Bondesil-C18 as a sorbent material was evaluated for the dynamic headspace analysis of a family of nine synthetic musks compounds that include two nitro musks, six polycyclic musks (with galaxolide and tonalide as the most widespread used polycyclic musks) and the degradation product of galaxolide (galaxolidone) in wastewater samples. Different parameters affecting the adsorption capacity of the sorbent were studied (e.g. extraction mode, extraction temperature, salt concentration, preincubation time fill and ejection speed or fill volume). Furthermore, injection parameters used with the NT device (e.g. desorption mode, desorption temperature and time) were evaluated to optimize the desorption and transfer of the target compounds into the GC column. Method detection limits obtained with gas chromatography-tandem mass spectrometry (GC-MS/MS) detection were found in the low ng L(-1) range, between 2.5 and 10 ng L(-1), depending on the target compounds. Moreover, under optimized conditions, the method gave good levels of intra-day and inter-day repeatabilities in wastewater samples with relative standard deviations (n=5, 100 ng L(-1)) less than 11 and 17%, respectively. The developed method was satisfactorily applied to the analysis of aqueous samples obtained from three wastewater treatment plants. All the polycyclic musks studied were detected in influent samples with cashmeran, galaxolide and tonalide as the most representative compounds. The analysis of effluent wastewater showed a decrease in the concentrations of all of the polycyclic musk detected in influent samples and an increase in the concentration of galaxolidone until a maximum value of 820 ng L(-1).