Seite - 171 - in Freshwater Microplastics - Emerging Environmental Contaminants?

polymer-dependent (PP vs. HDPE) aggregations with the algaeChlamydomonas reinhardtii. While rapid colonization of the surfaces of both HDPE and PPwas observed, expandinghetero-aggregatesconsistingofpolymerparticles, algaecells, and exopolysaccharideswere solely formed by PP. The upscaling ofmicroscopic particles via aggregation canmodify their potential for being ingested.While the abundance of microscopic particles and thereby the availability to micro-feeders (e.g., protozoans, planktonic crustaceans) decreases, large hetero-aggregates are accessible to macro-feeders (e.g., planktivorous fishes). Thus, the uptake of one aggregate by macro-feeders might lead to an internal release and exposure to multipleparticlesofdifferentsizesasdigestivefluidsdigest thebiopolymermatrix. However, the sample preparation needed to separate MPs from environmental Fig. 2 Schematic overview of interactions between microplastics, biota, and ecosystems. The term microplastics comprises the following interdependent factors: A additives (e.g., polymer monomers, production residues), P pollutants (e.g., HOCs), B biofilm and biopolymers,MP microplastics includingvarieties ofmaterial, density, shape, size, and surface characteristics Interactions ofMicroplasticswithFreshwaterBiota 171