Jiaying Li, Xiaotong Cen, Qiuda Zheng, Zeyang Zhao, Jianan Ren, Stuart Khan, Haoran Duan, Phong Thai, Min Zheng
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引用次数: 0
Abstract
Magnesium hydroxide (Mg(OH)₂) dosing is widely applied for sewer odour control. However, its impact on the fate of biomarkers used for wastewater-based epidemiology (WBE) has been overlooked. This study investigated the long-term and short-term impact of Mg(OH)₂ dosing on in-sewer transformation of 20 biomarkers. The dosing duration and amount of Mg(OH)₂ were specifically controlled in laboratory-scale sewer reactors, which led to long-term biofilm adaptation and instant change of wastewater pH. Mg(OH)₂ dosing rapidly inhibited H₂S at high pH levels and changed microbial community structure after long-term exposure. The transformation of biomarkers was a combined result of pH-driven abiotic process and biodegradation in the dosing-impacted sewers. The high stability of biomarkers like acesulfame and carbamazepine was unaffected by Mg(OH)₂ dosing. Most unstable biomarkers like caffeine, codeine and nicotine presented less degradation and extended half-lives in sewers received either long-term or short-term dosing, compared to their rapid losses under normal sewer conditions. This study provides a comprehensive understanding of both instant and lasting impacts of Mg(OH)₂ dosing on microbial community, biological activity, and biomarker stability in sewers. The longer half-lives of biomarkers in Mg(OH)2-dosed sewers benefited WBE application due to the improved detection reliability and less uncertainty related to biomarker loss, suggesting that chemical dosing information is required for accurate WBE estimation within a catchment.
期刊介绍:
Water Research, along with its open access companion journal Water Research X, serves as a platform for publishing original research papers covering various aspects of the science and technology related to the anthropogenic water cycle, water quality, and its management worldwide. The audience targeted by the journal comprises biologists, chemical engineers, chemists, civil engineers, environmental engineers, limnologists, and microbiologists. The scope of the journal include:
•Treatment processes for water and wastewaters (municipal, agricultural, industrial, and on-site treatment), including resource recovery and residuals management;
•Urban hydrology including sewer systems, stormwater management, and green infrastructure;
•Drinking water treatment and distribution;
•Potable and non-potable water reuse;
•Sanitation, public health, and risk assessment;
•Anaerobic digestion, solid and hazardous waste management, including source characterization and the effects and control of leachates and gaseous emissions;
•Contaminants (chemical, microbial, anthropogenic particles such as nanoparticles or microplastics) and related water quality sensing, monitoring, fate, and assessment;
•Anthropogenic impacts on inland, tidal, coastal and urban waters, focusing on surface and ground waters, and point and non-point sources of pollution;
•Environmental restoration, linked to surface water, groundwater and groundwater remediation;
•Analysis of the interfaces between sediments and water, and between water and atmosphere, focusing specifically on anthropogenic impacts;
•Mathematical modelling, systems analysis, machine learning, and beneficial use of big data related to the anthropogenic water cycle;
•Socio-economic, policy, and regulations studies.