Surface Aging Behavior of Polystyrene Microplastics in Leachate and Enrichment of Antibiotic Resistance Genes

Abstract:

Polystyrene （PS） microplastics （MPs） were taken as an example to analyze its aging pattern in leachate， as well as the enrichment effect of aging process on antibiotic resistance genes （ARGs） and the enrichment mechanism. The results show that the specific surface area and oxygen-containing groups of PS microplastics increase after 90 d of aging. ARGs can be selectively enriched on the surface of PS microplastics in leachate， and the degree of enrichment increases with the aging time. Furthermore， the genus-ARGs co-correlation network and the gene expression prediction were used to reveal the mechanism of ARGs enrichment. It is found that the niche formed on the surface of PS microplastics has closer ARGs-microbe correlation， and the expression level of genes involved in ARGs spread is higher.

Key words:microplastics (MPs);antibiotic resistance genes (ARGs);leachate;surface aging process;enrichment effect