http://dx.doi.org/10.1021/es501090e

Andrew J. R. Watts, Ceri Lewis, Rhys M. Goodhead, Stephen J. Beckett,
Julian Moger, Charles R. Tyler, and Tamara S. Galloway
Uptake and Retention of Microplastics by the Shore Crab Carcinus maenas
Environ. Sci. Technol., 2014, 48 (15), pp 8823?8830
DOI: 10.1021/es501090e

Abstract
Microplastics, plastics particles <5 mm in length, are a widespread
pollutant of the marine environment. Oral ingestion of microplastics has
been reported for a wide range of marine biota, but uptake into the body
by other routes has received less attention. Here, we test the
hypothesis that the shore crab (Carcinus maenas) can take up
microplastics through inspiration across the gills as well as ingestion
of pre-exposed food (common mussel Mytilus edulis). We used
fluorescently labeled polystyrene microspheres (8?10 ?m) to show that
ingested microspheres were retained within the body tissues of the crabs
for up to 14 days following ingestion and up to 21 days following
inspiration across the gill, with uptake significantly higher into the
posterior versus anterior gills. Multiphoton imaging suggested that most
microspheres were retained in the foregut after dietary exposure due to
adherence to the hairlike setae and were found on the external surface
of gills following aqueous exposure. Results were used to construct a
simple conceptual model of particle flow for the gills and the gut.
These results identify ventilation as a route of uptake of microplastics
into a common marine nonfilter feeding species.