Author(s)

Z. Shu, A. Singh, N. Klamerth, K. McPhedran, P. Chelme-Ayala, J. R. Bolton, M. Belosevic, M. Gamal El Din

Abstract

The occurrence of a variety of contaminants of emerging concerns (CECs) such as hormones and pharmaceuticals in municipal wastewater is an ongoing concern. In this study, UV/hydrogen peroxide (H₂O₂) was applied to treat the secondary effluent from Gold Bar Wastewater Water Treatment Plant in Edmonton, Alberta, Canada. Bench-scale tests were conducted to investigate the direct UV photolysis and UV/H₂O₂ oxidation of nine selected model micropollutants. The quantum yields at pH 7 were found to be between 0.0010 and 0.13. To investigate the effect of the water matrices, the degradation rate constants for 2,4-D and carbamazepine were determined in MilliQ water and wastewater. Overall, the estimated rates were higher in MilliQ water than those estimated in actual wastewater samples with differences of 34 and 37% for 2,4-D and carbamazepine, respectively. Differences in the pseudo first-order rate constants could be attributed to the matrix effects of the wastewater. The pilot-scale UV/H₂O₂ process did not appear to be able to remediate acute estrogenic activities in the reuse water to goldfish, whereas it had the potential to minimize the estrogenic effects of the reuse water in chronic exposures.

Keywords

micropollutants, endocrine disruption, estrogenic effects, reuse water, UV/H₂O₂ process, fluence-based degradation rate constant