Exploration of optimal disinfection model based on groundwater risk assessment in disinfection process

Cuihong Han; Shanghai Du; Wenjing Zhang; Dayi Zhang; Zong Wen; Juanfen Chai; Kaichao Zhao; Simiao Sun

doi:10.1016/j.ecoenv.2023.115107

Exploration of optimal disinfection model based on groundwater risk assessment in disinfection process

Ecotoxicol Environ Saf. 2023 Aug:261:115107. doi: 10.1016/j.ecoenv.2023.115107. Epub 2023 Jun 6.

Authors

Cuihong Han¹, Shanghai Du², Wenjing Zhang³, Dayi Zhang⁴, Zong Wen⁴, Juanfen Chai⁴, Kaichao Zhao⁴, Simiao Sun⁵

Affiliations

¹ Key Laboratory of Groundwater Resources and Environment (Jilin University), Ministry of Education, Changchun 130021, China; College of Construction Engineering, Jilin University, Changchun 130021, China.
² Key Laboratory of Groundwater Resources and Environment (Jilin University), Ministry of Education, Changchun 130021, China; College of Construction Engineering, Jilin University, Changchun 130021, China; College of New Energy and Environment, Jilin University, Changchun 130021, China.
³ Key Laboratory of Groundwater Resources and Environment (Jilin University), Ministry of Education, Changchun 130021, China; College of New Energy and Environment, Jilin University, Changchun 130021, China. Electronic address: zhangwenjing80@hotmail.com.
⁴ Key Laboratory of Groundwater Resources and Environment (Jilin University), Ministry of Education, Changchun 130021, China; College of New Energy and Environment, Jilin University, Changchun 130021, China.
⁵ School of Geography, Earth and Environmental Sciences, University of Birmingham, UK.

PMID: 37290298
DOI: 10.1016/j.ecoenv.2023.115107

Abstract

Under the influence of different types of disinfectants and disinfection environments, the removal level of pathogens and the formation potential of disinfection by-products (DBPs) will have a dual impact on the groundwater environment. The key points for sustainable groundwater safety management are how to balance the positive and negative relationship and formulate a scientific disinfection model in combination with risk assessment. In this study, the effects of sodium hypochlorite (NaClO) and peracetic acid (PAA) concentrations on pathogenic E. coli and DBPs were investigated using static-batch and dynamic-column experiments, as well as the optimal disinfection model for groundwater risk assessment was explored using quantitative microbial risk assessment and disability-adjusted life years (DALYs) models. Compared to static disinfection, deposition and adsorption were the dominant factors causing E. coli migration at lower NaClO levels of 0-0.25 mg/L under dynamic state, while disinfection was its migration factor at higher NaClO levels of 0.5-6.5 mg/L. In contrast, E. coli removed by PAA was the result of the combined action of deposition, adsorption, and disinfection. The disinfection effects of NaClO and PAA on E. coli differed under dynamic and static conditions. At the same NaClO level, the health risk associated with E. coli in groundwater was higher, whereas, under the same PAA conditions, the health risk was lower. Under dynamic conditions, the optimal disinfectant dosage required for NaClO and PAA to reach the same acceptable risk level was 2 and 0.85 times (irrigation) or 0.92 times (drinking) of static disinfection, respectively. The results may help prevent the misuse of disinfectants and provide theoretical support for managing twin health risks posed by pathogens and DBPs in water treatment.

Keywords: Disinfection; Disinfection by-products; Groundwater risk assessment; Optimal disinfectant dosage; Pathogen; Twin health risks.

MeSH terms

Disinfectants* / pharmacology
Disinfection / methods
Escherichia coli
Groundwater*
Peracetic Acid
Risk Assessment
Water Purification* / methods

Substances

Disinfectants
Peracetic Acid