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Frontiers of Environmental Science & Engineering

ISSN 2095-2201

ISSN 2095-221X(Online)

CN 10-1013/X

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Front. Environ. Sci. Eng.    2024, Vol. 18 Issue (11) : 140    https://doi.org/10.1007/s11783-024-1900-8
Spatio-temporal characteristics of genotoxicity in the Yangtze River under the background of COVID-19 pandemic
Xinge Wang1,2,3,4,5, Na Li1,2,4(), Yingnan Han1,2,4, Xiao Li1,2,4, Weixiao Qi6, Jian Li7, Kaifeng Rao1,2,4, Zijian Wang1,2,4, Yanjie Wei8, Mei Ma1,2,4,5()
1. Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
2. State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
3. Yangtze Eco-Environment Engineering Research Center, China Three Gorges Corporation, Beijing 100038, China
4. National Engineering Research Center of Industrial Wastewater Detoxication and Resource Recovery, Beijing 100085, China
5. University of Chinese Academy of Sciences, Beijing 100049, China
6. Center for Water and Ecology, State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
7. Engineering Research Center of Groundwater Pollution Control and Remediation, Ministry of Education, College of Water Sciences, Beijing Normal University, Beijing 100875, China
8. Key Laboratory of Environmental Protection in Water Transport Engineering Ministry of Communications, Tianjin Research Institute of Water Transport Engineering, Tianjin 300456, China
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Abstract

● Genotoxicity was higher in upper Yangtze River than that in the lower reaches.

● COVID-19 changed the seasonal regularity of genotoxicity in lower Yangtze River.

● Water samples exhibited more pronounced genotoxicity compared to sediments.

● Direct genotoxicity being the primary factor and related to antiviral drugs and DBPs.

● 65% or 71% of water posed high or medium risk for Paramecium caudatum or Danio rerio.

Abstract The global spread of viruses can lead to the release of large amounts of disinfectants or antiviral drugs into the water environment. The resulting disinfection byproducts (DBPs) and residual antiviral drugs, acting as genotoxic substances or their precursors, may pose risks to aquatic animals and drinking water sources; however, to date, no studies have analyzed the changes in genotoxicity in the Yangtze River before and after the epidemic. In the present study, water and sediment samples from the Yangtze River were collected during different seasons, just before and after the outbreak of COVID-19, and were assessed using the SOS/umu test (with and without liver S9). The results indicated that water samples exhibited more pronounced genotoxicity than did sediments, with direct genotoxicity being the primary factor. Additionally, there were significant regional differences, with notably greater genotoxicity observed in the upper Yangtze River than in the lower reaches before the COVID-19 epidemic. However, this trend was reversed six to ten months later, suggesting the accumulation of DBPs or antiviral drugs after the COVID-19 pandemic. Moreover, the risk quotient indicated that 65% of the water samples posed a high risk for Paramecium caudatum, whereas 71% of the samples posed a medium risk for Danio rerio, thereby representing a potential threat to the ecological security of the Yangtze River. In conclusion, this study, at the basin scale, revealed the impacts of COVID-19 on the Yangtze River, highlighting the need to prevent DBPs and pharmaceutical pollution during similar events in the future.

Keywords Yangtze River      COVID-19      Genotoxicity      Spatio-temporal characteristics     
Corresponding Author(s): Na Li,Mei Ma   
Issue Date: 13 September 2024
 Cite this article:   
Xinge Wang,Na Li,Yingnan Han, et al. Spatio-temporal characteristics of genotoxicity in the Yangtze River under the background of COVID-19 pandemic[J]. Front. Environ. Sci. Eng., 2024, 18(11): 140.
 URL:  
https://academic.hep.com.cn/fese/EN/10.1007/s11783-024-1900-8
https://academic.hep.com.cn/fese/EN/Y2024/V18/I11/140
Fig.1  Distribution diagram of sampling sites in key Yangtze River sections.
Fig.2  Maximum IR values of gradient-diluted concentrated water samples (a−c) in the absence of S9 and (d) in the presence of S9.
Fig.3  TEQ4-NQO of concentrated water samples from the Yangtze River. The solid diamonds represent different sampling sites; the hollow diamonds and solid lines represent the means and medians of different sampling sites in the same section, respectively; and the upper and lower edges of the box represent the upper and lower quartiles, respectively. *p < 0.05, **p < 0.01.
Fig.4  Maximum IR values of gradient-diluted sediment samples (a−c) in the absence of S9 and (d) in the presence of S9.
Fig.5  TEQ4-NQO of sediment samples from Yangtze River. The solid diamonds represent different sampling sites; the hollow diamonds and solid lines represent the means and medians of different sampling sites in the same section, respectively; and the upper and lower edges of the box represent the upper and lower quartiles, respectively.
Fig.6  Risk quotient of water samples in Yangtze River at different periods of COVID-19.
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