Microplastics as vectors for environmental contaminants: Exploring sorption, desorption, and transfer to biota

Abstract

The occurrence and effects of microplastics (MPs) in the aquatic environment are receiving increasing attention. In addition to their possible direct adverse effects on biota, the potential role of MPs as vectors for hydrophobic organic chemicals (HOCs), compared to natural pathways, is a topic of much debate. It is evident, however, that temporal and spatial variations of MP occurrence do (and will) occur. To further improve the estimations of the role of MPs as vectors for HOC transfer into biota under varying MP concentrations and environmental conditions, it is important to identify and understand the governing processes. Here, we explore HOC sorption to and desorption from MPs and the underlying principles for their interactions. We discuss intrinsic and extrinsic parameters influencing these processes and focus on the importance of the exposure route for diffusive mass transfer. Also, we outline research needed to fill knowledge gaps and improve model-based calculations of MP-facilitated HOC transfer in the environment. Integr Environ Assess Manag 2017;13:488-493. © 2017 SETAC.

Quantifying ecological risks of aquatic micro- and nanoplastic

“…Although the role of microplastic ingestion in the bioaccumulation of POPs by organisms has been suggested to be minor for most aquatic habitats (Besseling, Foekema, Van Den Heuvel-Greve, & Koelmans, 2017;Endo & Koelmans, 2016;Herzke et al, 2016;Koelmans, Bakir, Burton, & Janssen, 2016;Koelmans et al, 2013;Lohmann, 2017;Ziccardi, Edgington, Hentz, Kulacki, & Kane Driscoll, 2016), there has been considerable debate on this. The hypothesis that microplastic affects bioaccumulation has dominated a large part of the microplastic research during the past decade, and both those scientists who do and those who do not think that microplastic increases the uptake of POPs find proof in experimental data (Besseling, Foekema, et al, 2017;Besseling et al, 2013;Chua, Shimeta, Nugegoda, Morrison, & Clarke, 2014;Hartmann et al, 2017;Koelmans et al, 2016;Rochman, Hoh, Kurobe, & Teh, 2013;Wardrop et al, 2016). The contrasting views can be explained by taking a closer look at the precise hypotheses that underlie the different studies.…”

Toxicity of Microplastics and Nanoplastics in Mammalian Systems

“…Plastic particles of less than 1 µm in size are also known as nanoplastics (NPs) [9,10]. These chemically inert MPs/NPs pose significant ecological and health concerns [5] because of their environmental persistence [6,11,12], potential ecotoxicity [13,14], and their ability to act as vectors for chemical pollutants [15][16][17] as well as pathogens [18,19].…”

Microplastic-mediated transport of PCBs? A depuration study with Daphnia magna

“…While the relative importance of microplastic for bioaccumulation of POPs, compared other matrices in the aquatic environment, is considered small – exploring contamiant transfer is relevant for understandning microplastic toxicity. Future studies should focus on describing both the physiochemical properties of the test microplastic, essential for predicting polymer sorptive capacity [41, 42], and, account for the microplastic effects on test organsisms biochemical composition due e.g., changes in food quality. There is, thereby, still a need of experimental data to quantify POP dynamics in systems containing microplastic for improving our understanding of their role in bioaccumulation of various contaminants, by different organisms, and at different pollution levels [19,42].…”