Aquatic contaminant

6PPD-quinone (6PPD-Q), a transformation product of tire antioxidants, has recently emerged as a potent aquatic contaminant with significant toxicological implications. This study investigated the sublethal effects of 6PPD-quinone (6PPD-Q) on lipid metabolism in Clarias gariepinus juveniles over a 28-day exposure. Fish were exposed to 500, 1000, and 1500 μg/L of 6PPD-Q, with positive and negative controls, following OECD (2019) guidelines. Lipid profile parameters total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and very-low-density lipoprotein cholesterol (VLDL-C) were analyzed to assess hepatotoxic and oxidative effects. Results (P <0.05) showed significant increases in TC and LDL-C, with concurrent reductions inHLDL-C and VLDL-C at higher concentrations, indicating oxidative stress and lipid dysregulation. Triglycerides exhibited an initial rise followed by depletion at the highest dose, suggesting disrupted β-oxidation. further mechanistic studies are recommended to elucidate the biochemical and molecular pathways affected by 6PPD-Q exposure.In conclusion, chronic 6PPD-Q exposure induced lipid imbalance and hepatocellular stress in C. gariepinus, underscoring the toxic potential of tire-derived pollutants in freshwater ecosystems