A comprehensive analytical approach to monitoring selected emerging contaminant classes in sewage sludge and e-waste from Norway

Sewage sludge and waste from electrical and electronic equipment (WEEE) constitute the most challenging materials to manage within a circular economy framework due to their complex composition and the presence of hazardous substances. Their increasing generation results in a wide variety of contaminants, highlighting the need for new strategies to ensure their proper management. Herein, an analytical procedure was developed for the analysis of 75 contaminants belonging to 7 contaminant classes in sewage sludge and WEEE: benzothiazoles, benzotriazoles, poly- and perfluorinated alkyl substances (PFAS), bisphenols, benzophenones, parabens, and monoester phthalate analogues and phthalic acid (mPHTs). The proposed methodology involved liquid-solid extraction (LSE) assisted by ultrasonication, followed by solid phase extraction (SPE) as a clean-up step, tailored to liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The methodology was successfully applied, obtaining method limits of quantification (mLOQs) ranging from 0.06 to 21.7 ng g⁻¹ in WEEE and from 0.26 to 43.6 ng g⁻¹ d.w. in sewage sludge. Median total concentrations of the target contaminants ranged from 22.5 to 257 ng g⁻¹ d.w. in sludge, and from 3.50 to 1025 ng g⁻¹ in WEEE. Removal efficiencies during the treatment of sludge were also assessed, demonstrating 89 % removal of the total concentrations during anaerobic digestion of sludge. Regarding WEEE, mPHTs demonstrated the highest detection rates, while PFAS were the least detected. This work improves the understanding of environmental contamination caused by emerging contaminants present in both sludge and WEEE and emphasizes the critical need for effective management.