Vol.:(0123456789) 1 3 Bulletin of Environmental Contamination and Toxicology https://doi.org/10.1007/s00128-019-02604-2 Evidence of Microplastic Ingestion by Fish from the Bahía Blanca Estuary in Argentina, South America Andrés H. Arias 1,2  · Ana C. Ronda 1,3  · Ana L. Oliva 1  · Jorge E. Marcovecchio 1,4,5 Received: 17 November 2018 / Accepted: 29 March 2019 © Springer Science+Business Media, LLC, part of Springer Nature 2019 Abstract The aim of this study was to assess – for the frst time – the occurrence and distribution of microplastics (MPs) in the gas‑ trointestinal tracts (GITs) of a marine commercial fsh species (Micropogonias furnieri) from the Bahía Blanca Estuary (BBE) in Argentina, and to evaluate fsh potential associated stress. In order to do this, juveniles were sampled using artisanal fshing arts at two sampling locations. Basic measurements of individual fsh were taken (total length, total weight, weight of the liver) and GITs were subsequently removed, digested with 30% H 2 O 2 for 5 days at 60°C, fltered on Whatman paper and then dried. Samples were observed with a stereomicroscope, and it was demonstrated that 100% of the individuals con‑ tained microplastic particles in their GITs. In total, 241 microplastic particles were removed from the GITs of all fsh. They were categorized as fbers (60.8%), pellets (28.9%), fragments (8.6%) and laminas (1.4%), and they ranged in size from 0.98 to > 5 mm. The average number of particles per fsh was higher than that reported in previous global marine studies. Moreo‑ ver, a positive correlation between the number of MPs per fsh and hepatosomatic index was found, suggesting a probable stress in their health condition. These fndings provide the frst and southernmost evidence of microplastic contamination in biota from the Argentinean sea, which is found in the South Atlantic sea. Keywords Plastic pollution · Fish · Fibers · Estuary · South America The use and production of plastic has dramatically increased over the past 65 years. Plastic is used in many everyday products that improve quality of life globally, yet around 50% of the plastic produced is used for disposable products that generate a substantial amount of waste (Nerland et al. 2014). As a result, plastic litter, arising from the inappropri‑ ate disposal of plastic products, is a major global problem. Microplastics (MPs) are defned as small pieces of plastic, typically < 5 mm in size; they are ubiquitous in waterbod‑ ies including lakes, seas and oceans (Andrady 2011). These particles can be found in personal care products (exfoliants, toothpaste, etc.) and typically enter aquatic environments via domestic wastewater streams. MPs can also be formed in situ from the degradation of larger plastic parts (MPs) when they are subjected to weathering by sun, oceanic and open coastal environments. There are several types of adverse efects of MPs on the marine environment. Ocean creatures that eat these tiny pieces of plastic can experience direct physical efects, such as the inhibition or slowing down of diges‑ tion, excretion or other body functions. In addition, several reports suggest that MPs have the potential to enter other parts of the body, such as the circulatory system, muscles and hepatic tissue (Akhbarizadeh et al. 2018; Avio et al. 2015; Collard et al. 2017; Farrell and Nelson 2013). Estuaries, in particular, are valuable marine ecosystems that provide diverse goods and services. These include food, coastal protection and habitat for a wide variety of species, including seabirds, fsh and mammals. Among the services provided, estuaries commonly act as nursery areas for fsh * Andrés H. Arias aharias@iado‑conicet.gob.ar 1 Instituto Argentino de Oceanografía (IADO‑CONICET/ UNS), Bahía Blanca, Argentina 2 Departamento de Química, Universidad Nacional del Sur (UNS), Bahía Blanca, Argentina 3 Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur (UNS), Bahía Blanca, Argentina 4 Universidad Tecnológica Nacional‑Facultad Regional Bahía Blanca (UTN‑FRBB), Bahía Blanca, Argentina 5 Universidad de la Fraternidad de Agrupaciones Santo Tomás de Aquino, Gascón, 3145, 7600 Mar del Plata, Argentina