Microplastics and anthropogenic debris in the Pacific oyster (Magallana gigas) from the southern Buenos Aires coast, Southwest Atlantic

Orazi M.M.; Palacios P.; Fiori S.M.; Larrea Valdivia A.E.; Valenzuela Huillca C.J.; Amodeo M.; Arias A.H. · Environmental Monitoring and Assessment (2026) · DOI: 10.1007/s10661-026-15323-z

Resumen

We present the first analysis of microplastic (MP) occurrence in wild, non-native oysters (Magallana gigas) from a population consumed by humans on the southern coast of Buenos Aires, Argentina. Samples were collected from diverse locations, including commercial and military harbours, oil transport facilities, and industrial and recreational beaches. Following collection, the oysters underwent tissue digestion (30% H2O2) and filtration (GF/F, 47 mm, 0.7 μm pore). Microplastic particles were examined using a Nikon SM-Z1500 lens and identified via Perkin Elmer micro-FTIR spectroscopy. Analysis of 145 individuals revealed 346 MP particles, with an average size of 1226.17 ± 47.73 μm. While microfibres were the dominant morphology, µFTIR analysis identified the polymers as polyacrylates, thermoplastic polyesters, styrene/isoprene block copolymers (SIS), and other anthropogenic materials. This study provides the first baseline data on MP contamination in wild oysters from a significant environmental region of the Western South Atlantic coastline, underscoring implications for food security and potential human health risks. © The Author(s), under exclusive licence to Springer Nature Switzerland AG 2026.

Instituciones: Universidad Nacional de San Agustín de Arequipa