Characterization of Microplastic-Associated Biofilm Development along a Freshwater-Estuarine Gradient

Abstract

Microplastic contamination is an increasing concern worldwide. Biofilms rapidly develop on surfaces in aquatic habitats, but the processes of biofilm formation and variation in bacterial community succession on different microplastics introduced into freshwater and estuarine environments are not well understood. In this study, the biofilm bacterial communities that developed on three different types of microplastics that are prevalent in the environment, high-density polyethylene (HDPE), polyethylene terephthalate (PET), and polystyrene (PS), was investigated. Virgin microplastics were incubated in microcosms over a period of 31 days with water collected along a freshwater-estuarine gradient of the Raritan River in New Jersey. Through long-read MinION sequencing of bacterial ribosomal operons, we were able to examine biofilm bacterial communities at a species- and strain-level resolution. Results indicated that both salinity level and microplastic type impacted biofilm formation and promoted colonization by distinct microbial communities. Limnobacter thiooxidans was found to be one of the most abundant microplastics colonizing-bacteria, and it is hypothesized that different types of microplastics could select for different strains. Our findings indicate that multiple groups of highly similar L. thiooxidans rRNA operons could be discerned within the community profiles. Phylogenetic reconstruction further established that various Linmobacter species uniquely colonized the different microplastics from the different sampling sites. Our findings indicate that microplastics support abundant and diverse bacterial communities and that the various types of microplastics can influence how different bacterial biofilms develop, which may have ecological impacts on aquatic ecosystems.

Calibration of Perfluorinated Alkyl Acid Uptake Rates by a Tube Passive Sampler in Water

“…There was no obvious difference between the mass of PFAS on clean and biofouled tubes during concurrent laboratory experiments (Figure ). This could be explained by considering how a thin, high-water-content layer of algae, sponge, or other organic matter (Figure S8) compares to the thick polyethylene membrane in thickness and permeability. , However, biofouling conditions are very difficult to recreate in the laboratory, and the conditioning of these field-exposed tubes likely altered the biofouling layer. Further experiments, such as tube deployments in a laboratory setting with live algae/bacteria, might be necessary to better assess the impact of biofouling on PFAS uptake. …”

Microplastics Reshape the Fate of Aqueous Carbon by Inducing Dynamic Changes in Biodiversity and Chemodiversity

“…A previous study showed that the dominant MP polymer types in the Haihe River were polypropylene (PP), polyethylene (PE), and polystyrene (PS) . Particles composed of PS, a typical MP polymer, tend to be retained in overlying water because they have low density (0.96–1.05 g/cm 3 ); therefore, they have been widely applied to study the impact of MPs on aquatic systems. , In aquatic systems, the concentration of MPs is <1 mg/L, and the median is 0.1 mg/L . The MP concentration in some rivers and lakes is more than 0.1 mg/L, as listed in Table S3.…”

Bioaccessibility of Microplastic-Associated Antibiotics in Freshwater Organisms: Highlighting the Impacts of Biofilm Colonization via an In Vitro Protocol

“…Virgin microplastics were obtained by pulverizing plastic boxes that were sieved to produce a fraction of particles with size ranges of 750–1000 μm, which then underwent UV irradiation to create photoaged microplastics (details on the preparation of microplastics are provided in Text S1). The size range was selected based on the dominant occurrence in the natural environment and a previous study on biofilm incubation. , The morphology and chemical components of microplastics are shown in Figure S2. Other reagents are described in Text S1.…”

“…The size range was selected based on the dominant occurrence in the natural environment and a previous study on biofilm incubation. 38,39 The morphology and chemical components of microplastics are shown in Figure S2. Other reagents are described in Text S1.…”