Mapping Emerging Contaminants in Wastewater Effluents through Multichromatographic Platform Analysis and Source Correlations

This study explores the correlation of contaminants of
emerging
concern (CECs) in wastewater effluents using liquid chromatography
(LC), supercritical fluid chromatography (SFC), and comprehensive
two-dimensional gas chromatography (GC × GC) with derivatization,
all coupled to high-resolution mass spectrometry (HRMS). Over 300
compounds, including frequently overlooked highly polar and nonpharmaceutical
CECs, were identified. Monitoring programs mainly focus on reducing
variability and assessing pollution in wastewater treatment plant
(WWTP) effluents under dry weather conditions, often neglecting wet-weather
discharges. In this study, correlation analysis revealed the complex
impact of rainfall on wastewater effluent composition, identifying
clusters of CECs introduced through rain runoff and discharges from
retention basins. Rain events affected the removal efficiency of easily
degradable CECs, with variations between WWTPs. Persistent compounds
such as PFAS demonstrated strong intragroup correlations, reflecting
their common sources and environmental stability. These findings provide
valuable insights into the diverse profiles of CECs in wastewater
and demonstrate the potential of correlation-based approaches to optimize
treatment strategies to the specific challenges of individual WWTPs.