An automated headspace solid-phase microextraction followed by gas chromatography–mass spectrometry method to determine macrocyclic musk fragrances in wastewater samples

Abstract

A fully automated method has been developed for determining eight macrocyclic musk fragrances in wastewater samples. The method is based on headspace solid-phase microextraction (HS-SPME) followed by gas chromatography–mass spectrometry (GC-MS). Five different fibres (PDMS 7 μm, PDMS 30 μm, PDMS 100 μm, PDMS/DVB 65 μm and PA 85 μm) were tested. The best conditions were achieved when a PDMS/DVB 65 μm fibre was exposed for 45 min in the headspace of 10 mL water samples at 100 °C. Method detection limits were found in the low ng L⁻¹ range between 0.75 and 5 ng L⁻¹ depending on the target analytes. 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, 1,000 ng L⁻¹) less than 9 and 14 %, respectively. The applicability of the method was tested with influent and effluent urban wastewater samples from different wastewater treatment plants (WWTPs). The analysis of influent urban wastewater revealed the presence of most of the target macrocyclic musks with, most notably, the maximum concentration of ambrettolide being obtained in WWTP A (4.36 μg L⁻¹) and WWTP B (12.29 μg L⁻¹), respectively. The analysis of effluent urban wastewater showed a decrease in target analyte concentrations, with exaltone and ambrettolide being the most abundant compounds with concentrations varying between below method quantification limit (<MQL) and 2.46 μg L⁻¹.