Toxicity of polystyrene microplastics on juvenile Oncorhynchus mykiss (rainbow trout) after individual and combined exposure with chlorpyrifos‎

Microplastic (MP) sorption and transfer of chemical contaminants has been widely reported, yet few studies have investigated combined effects contaminant-loaded MPs on organisms. This study examined pristine or chlorpyrifos (CPF)-loaded polystyrene (PS)‎ fragments histopathological histomorphometrical biomarkers in rainbow trout (Onchorhynchus mykiss)‎. In laboratory, O. mykiss were exposed for 96 h to PS-MPs concentrations (30 300 µg/L), CPF ‎alone (2 ‎‎6 the same presence aquaria‎. Results showed highest alterations both when with fish gills. Alternatively, high lesions including massive necrosis, infiltration inflammatory cells, shed villi tips observed gut PS-MP ‎(6 μg/L CPF+300 PS-‎MPs). Individual together significant changes gills, skin. Findings highlight that cause toxicity increase adverse mykiss, especially gill tissue. We present evidence short-term exposure even low a impact biomarker responses mykiss.