Microplastic aging alters the adsorption-desorption behaviors of sulfamethoxazole in marine animals: A study in simulated biological liquids

• Published in: Marine pollution bulletin Vol. 195; p. 115473
• Main Authors: Li, Jiaxuan, Li, Yunxue, Maryam, Bushra, Chen, Xiaochen, Zong, Yanping, Tu, Jianbo, Zhang, Pingping, Liu, Xianhua
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.10.2023
• Subjects: Adsorption-desorption; Microplastics; Sulfamethoxazole; UV-aging; Sulfamethoxazole; Microplastics; Adsorption-desorption; UV-aging
• ISSN: 0025-326X; 1879-3363
• DOI: 10.1016/j.marpolbul.2023.115473

Antibiotics and microplastics (MPs) coexisting as unique environmental contaminants may cause unintended environmental issues. In this study, the adsorption-desorption behaviors of sulfamethoxazole (SMX) on both original and UV-aged MPs were examined. Polyhydroxyalkanoates (PHA) and polyethylene (PE), which represent degradable and refractory MPs, respectively, were chosen as two distinct types of MPs. Furthermore, simulated fish intestinal fluids (SFIF) and simulated mammalian stomach fluids (SMGF) were employed to evaluate the desorption behaviors of SMX from aged MPs. Our findings demonstrate that UV-aging altered the polarity, hydrophilicity, and structure of the MPs. Aged MPs showed a higher adsorption capacity than the original MPs and they have a higher desorption capacity than original MPs in simulated body fluids. PE has a higher SMX desorption capacity in SFIF and the opposite happened in SMGF. Our results highlight the importance of considering the different adsorption-desorption behaviors of antibiotics on MPs when evaluating their environmental impact. [Display omitted] •Desorption behavior of SMX was analyzed in two simulated biological liquids.•Impact of microplastic aging on the adsorption of SMX onto MPs•The environmental risks associated with degradable MPs should not be overlooked.•Combined contamination can pose aggravated risks to certain marine animals.