The toxicological studies of cadmium (Cd), lead (Pb) and manganese (Mn), were carried out on albino
rat. Twenty five rat classified to five equal groups. First group was given water contain Cd, Pb and Mn,
as (0.54g /L ,0.73g L 0.54g /L)respectively and kept as positive control. Second, third and forth groups
were given water (orally by stomach tube 1ml/rat/day for 2 month) contain some pollutant as first group
but after treatment with alum, ferric chloride and Pseudomonas bacteria respectively . Fifth group
administrated distal water and kept as control negative. At the end of experiment serum sample were
collected for estimation of Alanine amino transferase (ALT), Aspatrate amino transferase (AST) and
electrolytes (Na, Ca, Ph and K), liver samples collected for determination of oxidative cascade and
samples from liver and kidney were collected for residues and histopathological examination. The result
indicated that the forth group (given water treated with Pseudomonas bacteria) showed less toxic effect
than other groups (second and third) in which water was treated by alum and ferric chloride respectively.
We can concluded that removal of heavy metal from water by bacteria was more effective than removal
by ferric chloride which was more effective than removal by alum.
Key words: Heavy metal, oxidative stress, residues