Microplastics in Abiotic and Biotic Parts of the Mesha Bay of the Kuibyshev Reservoir (Republic of Tatarstan)

A study of the microplastic (MP) content in water, sediments, and gills and gastrointestinal tract (GIT) of bream (Abramis brama L., 1758) at the mouth of the Mesha River (right tributary of the Kama River) has been conducted. The content of MPs in water is found at the level of 20.5 ± 22.3 items/m³, in bottom sediments (BSs) 44.7 ± 41.8 items/kg, in fish gills 12.3 ± 8.4 items/individual, and in the GIT 14.5 ± 11.5 items/individual. Fibers dominate in water samples and in the gills and GIT of fish; fragments dominate in the sediments. Correlation analysis has shown the presence of a negative relationship between the content of MPs in the gills, GIT, and biological parameters of the fish. In terms of the frequency of occurrence and content of MPs in the gills and GIT, the contamination of the studied fish is at a high level when compared to literature data, which is due to the feeding behavior of bream.