Suspect and non-target screening workflow for studying the occurrence, fate, and environmental risk of contaminants in wastewater using data-independent acquisition

Abstract

A comprehensive suspect and non-target screening workflow based on liquid chromatography coupled to a quadrupole-time-of-flight mass spectrometer was developed for the detection and identification of contaminants in wastewater using data-independent acquisition. The suspect screening workflow could identify 74 compounds from different classes (mainly pharmaceuticals and pesticides), of which37 compounds were confirmed by reference standards.The remaining 37 compounds were tentatively identified based on MS/MS spectra match. The occurrence and elimination of the identified compounds were studied and discussed in detail. Furthermore, the confirmed compounds were quantified where pharmaceuticals had the greatest overall concentrations in all samples, followed by flame retardants. The non-steroidal antiandrogen, bicalutamide, was detected at the highest concentration (843.9 to 3838 ng/L) at the wastewater effluents, where the flame retardant, tris(2-butoxyethyl) phosphate, exhibited a concentration in the range of 337.2 to 1304.6 ng/L. Consequently, the environmental toxicity and risk of the confirmed compounds were investigated. The pharmaceutical, telmisartan, with the insecticide, fipronil exhibited high-risk quotients ( 600∼1400 and 102∼290, respectively), demonstrating their potential toxicity at ecologically relevant amounts. Finally, multivariate analysis was applied to evaluate the efficiency of wastewater treatment . Principal component analysis was able to clearly discriminate between influent and effluent samples, demonstrating an effective treatment process..