The prevalence of microplastics (<5 mm) in natural environments has become a widely recognised global problem. Microplastics have been shown to sorb chemical pollutants from their surrounding environment, thus raising concern as to their role in the movement of these pollutants through the food chain. This experiment investigated whether organic pollutants sorbed to microbeads (MBs) from personal care products were assimilated by fish following particle ingestion. Rainbow fish (Melanotaenia fluviatilis) were exposed to MBs with sorbed PBDEs (BDE-28, -47, -100, -99, -153, -154, -183 200 ng g-1; BDE-209 2000 ng g-1) and sampled at 0, 21, 42 and 63 days along with two control treatments (Food Only and Food + Clean MBs). Exposed fish had significantly higher ∑8PBDE concentrations than both control treatments after just 21 days, and continued exposure resulted in increased accumulation of the pollutants over the experiment (ca. 115 pg g-1 ww d-1). Lower brominated congeners showed highest assimilation whereas higher brominated congeners did not appear to transfer, indicating they may be too strongly sorbed to the plastic or unable to be assimilated by the fish due to large molecular size or other factors. Seemingly against this trend, however, BDE-99 did not appear to bioaccumulate in the fish, which may be due to partitioning from the MBs or that it was metabolised in vivo. This work provides evidence that MBs from personal care products are capable of transferring sorbed pollutants to fish that ingest them.
Peter Wardrop, Jeff Shimeta, Dayanthi Nugegoda, Paul D Morrison, Ana Miranda, Min Tang, and Bradley Owen Clarke, Environ. Sci. Technol., Vol. 50 (7), pages 4037-4044, April 2016