Volume 178, Pages 1-502 (July 2013)

Stephanie L. Wright, Richard C. Thompson, Tamara S. Galloway, The physical impacts of microplastics on marine organisms: A review, Environmental Pollution, Volume 178, July 2013, Pages 483-492, ISSN 0269-7491, 10.1016/j.envpol.2013.02.031.
(http://www.sciencedirect.com/science/article/pii/S0269749113001140)
Abstract: Plastic debris at the micro-, and potentially also the nano-scale, are widespread in the environment. Microplastics have accumulated in oceans and sediments worldwide in recent years, with maximum concentrations reaching 100 000 particles m³. Due to their small size, microplastics may be ingested by low trophic fauna, with uncertain consequences for the health of the organism. This review focuses on marine invertebrates and their susceptibility to the physical impacts of microplastic uptake. Some of the main points discussed are (1) an evaluation of the factors contributing to the bioavailability of microplastics including size and density; (2) an assessment of the relative susceptibility of different feeding guilds; (3) an overview of the factors most likely to influence the physical impacts of microplastics such as accumulation and translocation; and (4) the trophic transfer of microplastics. These findings are important in guiding future marine litter research and management strategies.
Keywords: Microplastics; Plastic debris; Marine litter; Marine invertebrates; Food web

Volume 177, Pages 1-204 (June 2013)

Paul Farrell, Kathryn Nelson, Trophic level transfer of microplastic: Mytilus edulis (L.) to Carcinus maenas (L.), Environmental Pollution, Volume 177, June 2013, Pages 1-3, ISSN 0269-7491, 10.1016/j.envpol.2013.01.046.
(http://www.sciencedirect.com/science/article/pii/S0269749113000614)
Abstract: This study investigated the trophic transfer of microplastic from mussels to crabs. Mussels (Mytilus edulis) were exposed to 0.5 μm fluorescent polystyrene microspheres, then fed to crabs (Carcinus maenas). Tissue samples were then taken at intervals up to 21 days. The number of microspheres in the haemolymph of the crabs was highest at 24 h (15 033 ml⁻¹ ± SE 3146), and was almost gone after 21 days (267 ml⁻¹ ± SE 120). The maximum amount of microspheres in the haemolymph was 0.04% of the amount to which the mussels were exposed. Microspheres were also found in the stomach, hepatopancreas, ovary and gills of the crabs, in decreasing numbers over the trial period. This study is the first to show ‘natural’ trophic transfer of microplastic, and its translocation to haemolymph and tissues of a crab. This has implications for the health of marine organisms, the wider food web and humans.
Keywords: Microplastic; Plastic; Polystyrene; Trophic; Transfer