Antibiotic Resistance Gene Enrichment on Plastic Wastes in Aquatic Ecosystems and Fishery Products

This comprehensive review gathers the current knowledge on the link between plastics wastes and antibiotic resistance genes (ARGs) selection and transmission in aquatic ecosystems that can lead to the ARG contamination of fishery products, a relevant source of MPs introduction in the food chain. Indeeed, plastic debris in aquatic environments aare covered by a biofilm (plastisphere) in which antibiotic-resistant bacteria (ARB) are selected and the horizontal gene transfer (HGT) of ARGs is facilitated. The types of plastic wastes considered in this study for their role in ARG enrichment are mainly microplastics (MPs) but also nanoplastics (NPs) and macroplastics. Studies regarding freshwaters, seawaters, aquaculture farms and ARG accumulation favored by MPs in aquatic animals were considered. Most studies were focused on the identification of the microbiota and its correlation with ARGs in plastic biofilms and a few evaluated the effect of MPs on ARG selection in aquatic animals. An abundance of ARGs higher in the plastisphere than in the surrounding water or natural solid substrates such as sand, rocks and wood was repeatedly reported. The studies regarding aquatic animals showed that MPs alone or in association with antibiotics favored the increase of ARGs in the exposed organisms with the risk of their introduction in the food chain. Therefore, the reduction of plastic pollution in waterbodies and in aquaculture waters could mitigate the ARG threat. Further investigations focused on ARG selection in aquatic animals should be carried out to better assess the health risks and increase the awareness on this ARG transmission route to adopt appropriate countermeasures.