Microplastic: A New Habitat for Biofilm Communities

Abstract

Since half a century, aquatic environments are polluted by plastic debris resulting in its global distribution even to remote systems. Immediately after entering the aquatic environment, microorganisms colonize on plastic surfaces and build up a biofilm, the so-called plastisphere. These epiplastic biofilms have been identified to play a key role in the fate and effects of environmental plastic but knowledge on epiplastic communities is scattered and often derives from laboratory experiments. Aim of this chapter is to shed light on the “triple role of biofilms” in fate and effects of environmental plastic to improve environmentally realistic research and risk assessment: (i) Biofilms can be shaped by the material properties in structure and functions. (ii) In turn biofilms influence the weathering, fate, and potential effects of plastic in the environment. (iii) Finally, plastic represents a new habitat for colonizing microorganisms, which might have system-wide interferences. Therefore, recent literature is reviewed illustrating the mechanisms of the first attachment of microorganisms on surfaces and their implications for weathering and fate of plastic in the environment. Current knowledge on the role of biofilms for partitioning of chemicals in the three-media system of plastic, biofilm, and the water phase is provided. Finally, insights into the potential ecologial role of epiplastic microbial communities for the aquatic environment are given. As plastic pollution has been identified even in remote systems, cross-system investigations considering the role of epiplastic biofilms for aquatic systems differing in vulnerability need to be performed to better inform environmental risk assessment of plastic pollution.