Toxicity of Zwitterionic Perfluorinated Compounds in Water Hyacinth

Abstract

Per- and polyfluoroalkyl substances (PFASs) pollution has become a hot environmental issue. PFASs have been detected in various types of environmental media and biological tissues, and the aquatic environment is an important “sink” for PFASs. As one of the most widely distributed organisms in aquatic environment, plants inevitably contact with PFASs, which may cause toxic effects in aquatic plants. However, most current studies focus on terrestrial plants and animals, but neglect the effects of PFASs in aquatic plants. Therefore, in this study, the freshwater plant, water hyacinth (Eichhornia crassipes), is selected as the research object to explore the toxic effects of zwitterionic perfluorinated compounds on aquatic plants. The results show that low concentration of perfluorooctaneamido betaine (PFOSB) (500 ng/L, 96 h) promotes the net photosynthetic rate of water hyacinth leaves, and the presence of perfluorooctanesulfonamido betaine (PFOAB) and PFOSB cause a significant increase in CAT activity in water hyacinth roots after 48 h. The antioxidant system is activated in response to the PFOAB and PFOSB stresses. This study provides a powerful theoretical basis for the toxic effects and ecological risks of zwitterionic PFASs in aquatic plants.