Microplastics in commercial bivalves harvested from intertidal seagrasses and sandbanks in the Ria Formosa lagoon, Portugal

September 27, 2022

Title

Microplastics in commercial bivalves harvested from intertidal seagrasses and sandbanks in the Ria Formosa lagoon, Portugal

Author

Lorenzo Cozzolino, Carmen B. de los Santos, Gerardo I. Zardi, Katy R. Nicastro

Year

2021

Journal

Cozzolino et al. 2021. Marine and Freshwater Research

Abstract

Through seafood consumption, microplastic (MP) pollution is potentially threatening human health.
Commercial bivalves in particular are a cause of major concern because their filter-feeding activity
directly exposes them to MP in the water column and they are then ingested by humans. Here, we
provide a quantitative and qualitative baseline data on MP content in the soft tissues of three
commercially important bivalves (Ruditapes decussatus, Cerastoderma spp. and Polititapes spp.)
collected in Ria Formosa lagoon, southern Portugal. The abundance of MPs (items per soft tissue
weight) did not significantly differ among species. On average, R. decussatus exhibited the highest
MP abundance (on average, 18.4 ± 21.9 MP items g–1 WW), followed by Cerastoderma spp. (11.9
± 5.5 MP items g–1 WW) and Polititapes spp. (10.4 ± 10.4 MP items g–1 WW). Overall, 88% of the
MPs found were synthetic fibres, the majority of which were blue (52%). Size categories >0.1–1 mm
and >1–5 mm were the most common (60% and 34% respectively). The most represented polymers
were polyethylene (PE) and polystyrene (PS). The unexpectedly high number of MPs recorded in the
three commercially exploited species suggests that this semi-closed lagoon system is experiencing a
higher anthropogenic pressure than are open coastal systems.

Instrument

NRS-4100, FT/IR-4700

Keywords

Cerastoderma spp., FTIR, marine debris, microfibers, Polititapes spp., Ruditapes decussatus, seafood.