Pollution Research Paper

STUDIES ON SOME PHYSICO-CHEMICAL PARAMETERS AND PESTICIDE RESIDUES IN SELECTED WETLANDS OF NORTH BIHAR CORRELATED WITH BIOCHEMICAL AND HISTOPATHOLOGICAL BIOMARKERS

PRAKRITI VERMA, PUSHPA KUMARI AND GYANENDRA BAHADUR CHAND

Abstract

In the present study serum Thyroid Stimulating Hormone (TSH) and histopathology of hepatic cells of two cat fishes Clarias batrachus (Linn.) and Heteropneustes fossilis (Bloch.) from three selected polluted wetlands of North Bihar were investigated through ELISA technique, light and transmission electron microscopy (TEM). The results obtained were compared with that of the fish from the reference site, considered as control. A comparative study of some physico-chemical parameters and presence of organochlorine residues in water of both reference site and test zones were also done. Serum TSH showed an enhanced level in the fishes of all the three test zones. The mean serum TSH of C.batrachus from test zones showed fluctuation between 0.032 ± 0.010 IU /mL to 0.027±0.022 IU/mL in comparison to the control fishes (0.002± 0.012 IU/mL). The mean serum TSH level of H. fossilis also showed elevation (0.019 ± 0.033 IU/mL) as compared to the control fish from the reference site (0.002 ± 0.011 IU/ mL). A plethora of histopathological changes were incurred in the hepatic cells of fishes from the test zones including persistent vacuoles in hepatic parenchyma, eccentric nucleus, peripheral fibrosis, increase in dimension of bile duct, hyperplasia, infiltration of lipids and congestion of central vein etc. TEM observations revealed heterochromatization, enucleation, dissolution of hepatic lobule boundary wall, prevalence of Kupffer cells and lysosomes with increased phagocytic activity. The study revealed a positive correlation between altered serum TSH and the structural deformities in hepatic cell of fishes of the test zones and polluted physico-chemical characteristics of water bodies. Altered TSH and hepatic atrophy in fish may be considered as biomarkers to know the pollution status of aquatic bodies.