Oral Presentation SETAC Asia-Pacific Virtual Conference 2022

Fate of emerging contaminants in different wastewater treatment systems: an investigation of removal mechanisms and treatment conditions (#9)

Monika Dubey 1 , Bhanu Prakash Vellanki 1 , Absar Ahmad Kazmi 1
  1. Indian Institute of Technology Roorkee, Roorkee, Uttarakhand, India

Wastewater effluent is a significant contributor to emerging contaminants (ECs) in the environment. The wastewater treatment plants are designed considering the regulated water quality parameters while ignoring the requirement for removing ECs. Though the actual environmental impacts of ECs are yet to be determined, specific influences such as genotoxicity, cytotoxicity, and endocrine disruptive effects are well reported. Monitoring of ECs through targeted and non-targeted screening approaches can be beneficial in studying the fate, temporal variation, and transport of emerging contaminants. The talk explores the use of an analytical approach for the quantification of 20 targeted polar to semi-polar emerging contaminants commonly reported in the Asian region using liquid chromatography-mass spectrometer and use of non-targeted screening approaches for the detection of transformation products. Ten full-scale municipal wastewater treatment plants based on seven different treatment technologies, including natural and engineered systems, were monitored over four years to detect the presence of ECs in wastewater and sludge treatment lines. Mass balance studies revealed biodegradation as the major removal mechanism, while sorption was the minor removal mechanism for the removal of parent compounds. A pilot-scale biological nutrient removal-based treatment plant was monitored to study the role of food/microorganism ratio and redox conditions on the removal and transformation of ECs. Results indicate that higher hydraulic retention time, low F/M ratio, and aerobic conditions improved the contaminant removal. The results can be used to optimize the conditions for the biological treatment of wastewater.