Acute and sublethal effects of acrylamide on the freshwater fish Anabas testudineus (Bloch, 1792)

Acrylamide, a synthetic compound, has a wide range of industrial applications that find multiple ways to reach aquatic ecosystem. The median lethal concentration of acrylamide determined using probit analysis in the fish Anabas testudineus was 132 µg L^-1 concentration together with altered behavioral patterns. Hematological and antioxidant status was evaluated at a sublethal concentration (one-tenth of LC₅₀-96 h), i.e., 13.2 µg L^-1 concentration for 24, 48, 72, and 96 h. A reduction in erythrocytes count, hemoglobin content, and packed cell volume with a significant (P < 0.05) increase in leukocyte counts and differential counts were observed. Erythrocyte indices like mean corpuscular volume (MCV) and mean corpuscular hemoglobin (MCH) increased, whereas the mean corpuscular hemoglobin concentration (MCHC) showed a significant (P < 0.05) decrease when compared with control groups. The activities of superoxide dismutase, catalase, and glutathione reductase in gill tissues showed significant (P < 0.05) reduction, whereas the levels of hydrogen peroxide and lipid peroxidation increased significantly (P < 0.05) indicating oxidative stress. The findings suggest that acrylamide at sublethal concentration caused alteration in hematological parameters and induced oxidative stress in gill tissue of the fish A. testudineus. Hence, restrictions on the use of acrylamide in food and industrial products are recommended since humans are the direct consumer of fish products.