Adsorption of heavy metals on biodegradable and conventional microplastics in the Pearl River Estuary, China. (1st April 2023)

• Record Type: Journal Article
• Authors: Shi, Min; Xie, Qun; Li, Zhen-Liang; Pan, Yun-Feng; Yuan, Zhen; Lin, Lang; Xu, Xiang-Rong; Li, Heng-Xiang
• Is Part Of: Environmental pollution. Volume 322(2023)
• Publication Date: 2023-04-01
• Subjects: Microplastics -- Heavy metals -- Adsorption -- Aging -- Environmental risk; Pollution -- Periodicals; Pollution -- Environmental aspects -- Periodicals; Environmental Pollution -- Periodicals; Pollution -- Périodiques; Pollution -- Aspect de l'environnement -- Périodiques; Pollution -- Effets physiologiques -- Périodiques; Pollution; Pollution -- Environmental aspects; Periodicals; Electronic journals; 363.73
• DOI: 10.1016/j.envpol.2023.121158
• Languages: English
• ISSNs: 0269-7491

Abstract

Abstract: In recent years, microplastics (MPs) as emerging carriers for environmental pollutants have attracted increasing worldwide attention. However, the adsorption of heavy metals on MPs, especially for biodegradable MPs, has been still poorly understood in estuarine environments. In this study, we investigated the aging of biodegradable and conventional MPs in the Pearl River Estuary after long-term exposure and their impacts on the adsorption of heavy metals from seawater. The results showed that the changes in surface characteristics were more prominent on biodegradable MPs than on conventional MPs after aging. Both biodegradable and conventional MPs could adsorb heavy metals, and their adsorption capacities fluctuated greatly on different MPs and different exposure times. The adsorption capacities of Cu, Pb, and As on biodegradable MPs were higher than those on conventional MPs, whereas Mn, Cr, and Co had lower adsorption on biodegradable MPs after 9–12 months by inductively coupled plasma-mass spectrometry (ICP-MS). The aging characteristics (CI, O/C, and X c ) of MPs accounted for a contribution of 51.0% on heavy metal adsorption, while the environmental factors (temperature, salinity, pH, and heavy metal concentration) only contributed to 13.2%. Therefore, the present study can provide important evidence on the environmental behaviors and ecological risks of biodegradable and conventional MPs in estuarine systems. Graphical abstract: Image 1 Highlights: Adsorption of heavy metals on biodegradable MPs was first reported in the Pearl River Estuary. The changes in the physicochemical property of biodegradable MPs were distinct. Biodegradable MPs tend to particularly adsorb Cu, Pb, and As. The aging properties of MPs had a strong relationship with heavy metal adsorption.