Effects of PAH Mixtures on Haematological, Hepatic and Oxidative Stress Biomarkers in Clarias gariepinus

Haematological, hepatic and oxidative stress parameters in juvenile Clarias gariepinus exposed to a combined ternary mixture of naphthalene, phenanthrene and benzo[a]pyrene were investigated under static-renewal bioassay conditions. The test organisms were exposed to two levels of treatments of the mixed compounds for a period of 35 days. Red blood cell (RBC) count, haemoglobin (Hb) concentration and haematocrit (Hct) were significantly lowered in exposed fish compared to the control. Significant decreases were also observed in mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH) and mean corpuscular haemoglobin concentration (MCHC). White blood cell (WBC) and platelet (PLT) counts were significantly raised in exposed organisms compared to the control. There were significant reductions in total plasma protein and bilirubin. While increases in superoxide dismutase (SOD) and catalase (CAT) were significant, that of glutahthione s-tranferase (GST) was not significant.