Potential spreading risks and disinfection challenges of medical wastewater by the presence of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) viral RNA in septic tanks of Fangcang Hospital

• Published in: The Science of the total environment Vol. 741; p. 140445
• Main Authors: Zhang, Dayi, Ling, Haibo, Huang, Xia, Li, Jing, Li, Weiwei, Yi, Chuan, Zhang, Ting, Jiang, Yongzhong, He, Yuning, Deng, Songqiang, Zhang, Xian, Wang, Xinzi, Liu, Yi, Li, Guanghe, Qu, Jiuhui
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01-11-2020
• Subjects: Betacoronavirus; Cabin hospital; China; Coronavirus Infections; COVID-19; Disinfection; Disinfection by-products; Humans; Motor Vehicles; Pandemics; Pneumonia, Viral; RNA, Viral - analysis; SARS-CoV-2; Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2); Wastewater; China; Disinfection; Disinfection by-products; Cabin hospital; Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2)
• ISSN: 0048-9697; 1879-1026; 1879-1026
• DOI: 10.1016/j.scitotenv.2020.140445

The outbreak of coronavirus infectious disease-2019 (COVID-19) pneumonia raises the concerns of effective deactivation of the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) in medical wastewater by disinfectants. In this study, we evaluated the presence of SARS-CoV-2 viral RNA in septic tanks of Wuchang Cabin Hospital and found a striking high level of (0.5–18.7) × 103 copies/L after disinfection with sodium hypochlorite. Embedded viruses in stool particles might be released in septic tanks, behaving as a secondary source of SARS-CoV-2 and potentially contributing to its spread through drainage pipelines. Current recommended disinfection strategy (free chlorine ≥0.5 mg/L after at least 30 min suggested by World Health Organization; free chlorine above 6.5 mg/L after 1.5-h contact by China Centers for Disease Control and Prevention) needs to be reevaluated to completely remove SARS-CoV-2 viral RNA in non-centralized disinfection system and effectively deactivate SARS-CoV-2. The effluents showed negative results for SARS-CoV-2 viral RNA when overdosed with sodium hypochlorite but had high a level of disinfection by-product residuals, possessing significant ecological risks.
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•First report on disinfection performance for SARS-CoV-2 in medical wastewater•Incomplete removal of SARS-CoV-2 RNA under WHO guideline•High level of DBPs when SARS-CoV-2 is completed removed.