RT info:eu-repo/semantics/bachelorThesis
T1 Occurrence of emerging pollutants in waste electrical and electronic equipment (WEEE) and sewage sludge from Norway
A1 Gutiérrez Martín, Daniel
A2 Universidad de Valladolid. Facultad de Ciencias
K1 WEEE
K1 Sewage sludge
K1 Benzotriazoles
K1 Benzothiazoles
AB Benzotriazoles (BTRs) and benzothiazoles (BTHs) are emerging pollutants ubiquitous in the environment due to their high production and wide use in industries and households. However, little information about their occurrence in the environment is available. In this project, the occurrence of 7 benzotriazoles, in particular, 1H-benzotriazole (BTR), xyliltriazole (XTR), 5-amino-benzotriazole (5-ABTR), 5-chlorobenzotriazole (5-Cl-BTR), 1-hydroxybenzotriazole (1-OH-BTR), benzotriazole-5-carboxylic acid (BTR-COOH) and tolyltriazole (TTR); and 9 benzothiazoles, i.e., benzothiazole (BTH), 2-amino-benzothiazole (2-ABTH), 2-mercaptobenzothiazole (2-S-BTH), 2-methylthio-benzothiazole (2-MeS-BTH), 2-hydroxy-benzothiazole (2-OH-BTH), 2-morpholin-4-yl-benzothiazole (2-M-BTH), 2-chlorobenzothiazole (2-Cl-BTH), 2-thiocyanomethylthio-benzothiazole (2-SCNMeS-BTH) and 2-methylbenzothiazole (2-Me-BTH) were studied in two different matrices, waste electrical and electronic equipment (WEEE) and sewage sludge, collected in different waste facilities in Norway. The proposed sample preparation included a liquid-solid extraction (LSE) assisted by ultrasound followed by a solid phase extraction (SPE) cleanup. Finally, the resulting extracts underwent an instrumental analysis based on ultra-high performance liquid chromatography coupled to a triple quadrupole mass spectrometer (UHPLC-ESI-QqQ). Out of the 16 initially proposed compounds, 11 were successfully validated in both matrices, which confirmed its high versatility. The limits of detection ranged between 0.02 and 1.67 ng L-1, and the linearity was satisfactory with R2 in the ranging between 0.9905 and 0.9971 for the selected 11 compounds. Precision was satisfactory with a RSD% intra-day below 22%, in all cases. The total concentration of BTRs in WEEE ranged between 3.8 and 496 ng g-1, being BTR the pollutant displaying the highest concentrations, followed by TTR. Regarding BTHs, the concentrations measured in WEEE presented values between 102 and 9,695 ng g-1, with the predominance of BTH. In sewage sludge samples, the occurrence and evolution of BTRs and BTHs during the treatment in the sewage treatment plants (STPs) showed a high persistence of TTR, XTR, BTR, 2-MeS-BTH and BTH. The evolution of some compounds as TTR or BTR differed between STPs, showing the differences between the treatments. Others like BTH and XTR were clearly degraded (or transformed). In contrast, 2-MeS-BTH showed to be very recalcitrant. The presence of high concentrations of BTRs and BTHs in the final sludge combined with its disposal in landfills or agricultural application as fertilizer, constitutes a serious environmental problem. Hence, using the data provided in this study, e.g., STP-3 would contribute with more than 2,300 and 5,000 kg y-1 of BTRs and BTHs, respectively, which could reach the environment affecting the wildlife and the crops. More research about the occurrence and behaviour of BTRs and BTHs in sewage sludge is still needed in order to find out the extension of human and environment exposition to these compounds, and its consequences in the ecosystem health. This study provided more light about the issue, and presented a multi-residue methodology which concomitantly analyses a high number of BTRs and BTHs. To the best of our knowledge, the occurrence of BTRs and BTHs in WEEE was assessed for the first time in this work.
YR 2021
FD 2021
LK https://uvadoc.uva.es/handle/10324/49990
UL https://uvadoc.uva.es/handle/10324/49990
LA eng
NO Departamento de Química Analítica
DS UVaDOC
RD 29-may-2024