Effect of Nanoplastic Type and Surface Chemistry on Particle Agglomeration over a Salinity Gradient

Abstract

Abstract Agglomeration of nanoplastics in waters can alter their transport and fate in the environment. Agglomeration behavior of 4 nanoplastics differing in core composition (red- or blue-dyed polystyrene) and surface chemistry (plain or carboxylated poly[methyl methacrylate] [PMMA]) was investigated across a salinity gradient. No agglomeration was observed for carboxylated PMMA at any salinity, whereas the plain PMMA agglomerated at only 1 g/L. Both the red and the blue polystyrene agglomerated at 25 g/L. Results indicate that both composition and surface chemistry can impact how environmental salinity affects plastic nanoparticle agglomeration. Environ Toxicol Chem 2021;40:1820–1826. © 2021 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. Abstract Nanoplastic agglomeration behavior across experimental salinity gradients varies depending on plastic type and surface chemistry. PMMA = poly(methyl methacrylate); PS = polystyrene.