Origins and Biological Accumulation of Small Plastic Particles in Fur Seals From Macquarie Island

In composition, they came from 5 polymer groups; polyethylene 93%, polypropylene 4%, poly(1-Cl-1-butenylene) polychloroprene 2%, melamine-urea (phenol) (formaldehyde) resin 0.5%, and cellulose (rope fiber) 0.5%. The larger groups are buoyant with a specific gravity less than that of seawater. These small plastic particles are formed from the breakdown of larger particles (fragments).

Their origin seems to be from the breakdown of user plastics washed ashore and ground down on cobbled beaches. Certainly most particles (70%) had attained their final form by active abrasion. It is hypothesized that the plastic particles were washed out to sea and then selected by size and consumed by individuals of a pelagic fish species, Electrona subaspera, who in turn were consumed by the fur seals.

Thus, the particles were accumulated both by the fish and the seals in the usual process of their feeding. The download file contains a pdf of the paper listed in the reference section below, as well as 48 scanning electron micrograph images of plastics recovered from fur seal scats.