A multi-biomarker approach to assess the exposure effects of MPs and/or sodium lauryl sulfate on Clarias Gariepinus

Pollutants impact fish health, leading to environmental diseases. Anionic surfactant detergents and MPs (MPs) consist serious threat in freshwater environments either lonely or in combination. However, their combined effects are not well studied. Our research therefore focuses on studying the harmful effects of the anionic surfactant sodium lauryl sulfate (SLS) and polyethylene MPs (PMPs) on the biology of freshwater African catfish (Clarias gariepinus), either alone or in combination. A 15-day exposure trial to PMPs (10 mg/L), SLS (4 mg/L), or their combination was conducted. Hematological, biochemical, antioxidant, and immunological markers were estimated. The erythrocytic morphology was investigated. The pathological harms were monitored, and the histological abnormalities were scored. In addition, histochemical appraisals of fibrosis and hypoglycemia in the liver and spleen were estimated. This was achieved by semi-quantification of polysaccharide deposits and the fibrotic collagen density and distribution pattern in the tissue micro-sections. On the one hand, our findings revealed deteriorated biological markers in C. gariepinus exposed to PMPs (10 mg/L) or SLS (4 mg/L) by close levels. Significant decreases in the hematological indices, while substantial increases in the biochemical markers were recorded. As well, significant decreases were recorded in the total antioxidant capacity and superoxide dismutase, while an elevation was recorded in the level of IL-1β and IL-6 cytokines. Poikilocytosis of erythrocytes and severe hepatic and splenic pathological lesions were observed. Furthermore, high levels of fibrosis and hypoglycemia were detected. On the other hand, our findings showed antagonistic effects upon the combined exposure to PMPs (10 mg/L) and SLS (4 mg/L). Fluctuated non-significant differences were observed in hematology and biochemical markers. Mild erythrocytic poikilocytosis and moderate pathological lesions were scored in liver as well as spleen. In addition, moderate quantitative fibrosis, and hypoglycemia were estimated. Exposure to PMPs and SLS deteriorate the biology and pathology of C. gariepinus by severe effects. Interestingly, ameliorated biological alterations were recorded evidenced a surprising antagonistic effect of PMPs + SLS. Possibly, a chemical chelation between both reagents counteracted their singular effect inside the biological system, which retorted their harm. Therefore, further investigations by chemists on the probable chemical interaction between PMPs and SLS inside biological systems, which might change their physical or chemical characteristics, may explain the case.