Occurrence and risk assessment of emerging contaminants in a water reclamation and ecological reuse project

Xiaohu Lin; Jingcheng Xu; Arturo A Keller; Li He; Yunhui Gu; Weiwei Zheng; Danyan Sun; Zhibo Lu; Juwen Huang; Xiangfeng Huang; Guangming Li

doi:10.1016/j.scitotenv.2020.140977

Occurrence and risk assessment of emerging contaminants in a water reclamation and ecological reuse project

Sci Total Environ. 2020 Nov 20:744:140977. doi: 10.1016/j.scitotenv.2020.140977. Epub 2020 Jul 15.

Authors

Xiaohu Lin¹, Jingcheng Xu², Arturo A Keller³, Li He⁴, Yunhui Gu⁴, Weiwei Zheng⁴, Danyan Sun⁴, Zhibo Lu⁵, Juwen Huang⁵, Xiangfeng Huang⁵, Guangming Li⁵

Affiliations

¹ State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China; Bren School of Environmental Science and Management, University of California, Santa Barbara, CA 93117, USA.
² State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China. Electronic address: xujick@tongji.edu.cn.
³ Bren School of Environmental Science and Management, University of California, Santa Barbara, CA 93117, USA.
⁴ State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.
⁵ State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China.

PMID: 32755786
DOI: 10.1016/j.scitotenv.2020.140977

Abstract

Water reclamation and ecological reuse is gradually becoming a popular solution to address the high pollutant loads and insufficient ecological flow of many urban rivers. However, emerging contaminants in water reuse system and associated human health and ecological risks need to be assessed. This study determined the occurrence and human health and ecological risk assessments of 35 emerging contaminants during one year, including 5 types of persistent organic pollutants (POPs), 5 pharmaceutical and personal care products (PPCPs), 7 endocrine disrupting chemicals (EDCs) and 18 disinfection by-products (DBPs), in a wastewater treatment plant (WWTP) and receiving rivers, as well as an unimpacted river for comparison. Results showed that most of PPCPs and EDCs, especially antibiotics, triclosan, estrogens and bisphenol A, occurred frequently at relatively high concentrations, and they were removed from 20.5% to 88.7% with a mean of 58.9% via WWTP. The highest potential noncarcinogenic and carcinogenic risks in different reuse scenarios were assessed using maximal detected concentrations, all below the acceptable risk limits, with the highest total combined risk value of 9.21 × 10^-9 and 9.98 × 10^-7, respectively. Ecological risk assessment was conducted using risk quotient (RQ) method and indicated that several PPCPs, EDCs and haloacetonitriles (HANs) pose high risk (RQ > 1) to aquatic ecology in the rivers, with the highest RQ up to 83.8. The study suggested that ecological risks need to be urgently addressed by updating and optimizing the process in WWTPs to strengthen the removal efficiencies of emerging contaminants. The study can serve as a reference for safer water reuse in the future, while further studies could be conducted on the health risk of specific groups of people, exposure parameters in water reuse, as well as more emerging contaminants.

Keywords: Ecological reuse; Emerging contaminants; Reclaimed water; Risk assessment; Water reuse.