Abundance of microplastics in oysters Crassostrea gigas and water from a highly anthropized estuary

MAIALEN ARDUSSO; BENJAMÍN ABASTO; CAROLINA COLOMBO; ANA FORERO-LOPEZ; CARLA SPETTER; NATALIA BUZZI; MELISA FERNÁNDEZ SEVERINI

Conferencia; Micro 2022; 2022

Microplastics -MPs- (plastic < 5 mm) have become one of the leading environmentalproblems due to the large amount released into aquatic and terrestrial ecosystems and theirpossible impacts on organisms and human health. Estuaries are positioned as sinks of MPs,due to the presence of natural and industrial effluents. In Argentina, the Bah ́ıa Blancaestuary -BBe- is the second largest estuary in the country and is highly anthropized since ithas one of the largest deep ports, the largest petrochemical complex, and urban settlementswith untreated sewage waters. The oyster C. gigas is widely used as MPs biomonitoring andis commonly distributed in BBe. This study assesses the concentrations of MPs in surfacewater and in whole tissue of oysters C. gigas, from the BBe. Two sites of the estuary weresampled, one in the inner zone and the other in the middle area. MPs ranged from 6 to 50items L-1 in water and from 0 to 2 ́ıtems g-1 ww in oyster tissue. There were no significantdifferences between the water samples and oysters (p > α = 0.25) according to the differentsites. Fibers were the most abundant MPs in water and oyster samples, with 78% and 95%,respectively. The color was mainly transparent, followed by blue and black. Regarding thesize in water, the MPs < 0.5 mm represented 50%, followed by particles between 1 and 5 mmwith 36%. In oysters, MPs between 1 and 5 mm were 48%. Many fibers could originate fromthe mechanical degradation of clothing textiles and hygiene products that enter the aquaticenvironment through sewage. Due to the ubiquitous nature of MPs in the environment andtheir different effects on organisms, studies of this kind represent the basis for implementingsustained monitoring of MPs in water, sediments, and biota.