SUBLETHAL EFFECTS OF LEAD ARSENATE ON HISTOLOGY OF SELECTED ORGANS OF FRESHWATER FISH CIRRHINUS MRIGALA

Acute toxicity (96 h LC50) of lead arsenate was evaluated in the Cirrhinus mrigala in static bioassay over a 96 –h exposure period using probit method. The 96 h LC50 values (with 95% confidence limits) of lead arsenate for fingerling fish were estimated as 7.21 mg/l respectively. Histopathological investigations revealed various degrees of pathological lesions in different organs like gill, liver, intestine and kidney. The gill showed the fusion, malformation of secondary lamellae at the tips, vaculation, hyperplasia and disintegration of epithelium. The liver of fish exposed to phenol showed cytoplasmic vaculation, necrosis and loss of hepatic cell wall. In the intestine, necrotic lesions in the epithelial layer, swellings and fusion with adjacent villi, fusion and integration of columnar epithelial layer. The kidney showed shrinkage of glomeruli, breakdown of Bowman’s capsule, vacuolization and disintegration of renal epithelium. The histological alterations in the fish could be used as an important tool for assessment of aquatic pollution