Combined effects of exposure to polyethylene microplastic and polycyclic aromatic hydrocarbons (PAHs): Histological changes in the neotropical species Astyanax lacustris Larissa Tais Traldi Wintruff, Juan Martins de Campos e Silva, Giorgi Dal Pont, Luciana R. de Souza-Bastos, Gisela G. Castilho-Westphal, Helen Sadauskas-Henrique

Abstract

Plastic materials have been used on a global scale for decades and the consequent presence of their residues in aquatic environments can cause adverse effects on organisms. Histological analyses are an excellent tool to evaluate these effects. The Bioindicator Astyanax lacustris is widely used to evaluate environmental contamination, such as by assessing histological damage in target tissues such as gills and liver. Elevation of epithelium cells and vascular congestion were the most frequent histologies found in the gill tissues, while deformation of the cell contour, disarrangement of the hepatic cords and nuclear vacuolization were the most frequent in the liver. These histologies were found in animals exposed to treatments with HPA, HPA+MP and contaminated MP. These results indicate that specimens of A. lacustres when exposed to microplastic and HPAs, alone or together, present histopathological changes in the branchial and hepatic tissues that basically occur as a result of defense responses or compensatory mechanisms.