The aim of present work was to study the toxicity of (mancozeb )Dithane
fungicide on fish Claras lazera (catfish) and consequently to human beings.The
fishes were exposed to Dithane in dose of 0.5 ppm /L (equivalent of 1/10 of
LD50)for 30 days. Different Haematological, Biochemical, Bacteriological, and
Immunological parameters were assessed. The results showed significant increase in
Blood level of Sodium (Na), Potassium (K), Cortisol, Urea, Creatinine, Glucose,
Insulin as well as Aspartate Amino Transferase (AST) and Alanine Amino
Transferease (ALT)in blood. However there was a decrease in blood level of Iron
and IgM, accompanied by decrease in Haemoglobin (HB), Macrocytic hypochromic
anemia (R.B.Cs) count, Packed cell volume (PCV) which was observed in fish in 7,
15, 30, days after exposure to Dithane. The Haemogram shows reticulocytosis and
increase in mean corpuscular volume (MCV). Dithane produces metabolic stress and
cell damage with malfunction of haemopoetic system. Microbiological examination
revealed a presence of pathogenic bacteria mainly E. coli, Flavabacterium, and
Staphylococcus aureus. It was concluded that in catfish reared on low dietary
carbohydrate (CHO) diet there was hyperglycemia due to increase in cortisol
hormone. However immunological results revealed decrease in the level of IgM in
blood; a loss of scales and petichial haemorrhage in parts of skin was observed.
Ascitic and erosion due to complication of bacterial infection, was also accorded.