Low numbers of microparticles were recovered from the tissue
of both species tested. In Mytilus edulis the average microplastic
load in the organisms without depuration was 0.36 ± 0.07 particles
per gram of soft tissue (wet weight (ww)). After the three day
depuration period, only 0.24 ± 0.07 particles g1 ww were recovered
(Fig. 2). The same trend was observed in Crassostrea gigas:
without depuration on average 0.47 ± 0.16 particles g1 ww were
found, while microplastic concentrations decreased to an average
of 0.35 ± 0.05 particles per gram soft tissue (ww) after depuratio
(Fendall and Sewell, 2009) and microplastic fibres from synthetic
fabrics such as polyester and polyamide (Browne et al., 2011;
Dubaish and Liebezeit, 2013). The impact of microplastics on marine
organisms will depend on a combination of parameters that
determine the position of these particles in the water column.
Typically, high-density particles will sink and accumulate in the
sediment, while low-density particles float at the sea surface,
although biofouling, turbulence and freshwater input may result in
vertical mixing