A total of 85 random raw milk and cheese samptes (40 raw cow’smilk and 45 samples from Damietta, hard and processed cheeses ”15samples each”) were collected from different outlets in DamiettaGovemorate during the period from October 1999 to September 2000. Rawmilk samples were collected from different dairies along the main road of heavy traffics during summer and winter seasons. All samples weredigested and analyzed by Atomic Absorption Spectrophotometry fordetermination of lead, cadmium, mercury, copper and zinc.Lead concentration in raw milk ranged from 0.850 to 2.725 ppm witha mean of 1.885 ppm during summer season, while in winter samples itvaried from 0.850 to 4.050 ppm with a mean of 2.268 ppm, meanwhile, theoverall mean of lead was 2.076 ppm in examined raw milk samples.Statistical analysis showed that 37 (92.5%) out of 40 raw milk samples,having lead level above its permissible limit. The calculated daily intake oflead was 415.2 ug for adult person and this amount representing 83.04% ofprovisional Acceptable Daily Intake. Cadmium level in raw milk samplesranged from 0.058 to 0.308 ppm with a mean of 0.120 ppm during summerbladder cancer. A total of twenty clinically healthy adult males and females mongrel dogs were used as an experimental animal model. These dogs were divided into four main groups. The first group of five dogs served as control and the last three groups ac1- Biochemical study. Different biochemical parameters weremeasured in sera and urine for control and operated groups, such ascreatinine (mg/dl), sodium (m mol/dl), potassium (m mol/dl), and totalprotein (mg/dl) 2-Urine culture and analysis study. Urine culture was done, and different parameters were analysed in urine samples. These were specificgravity, pH (unit), blood (ug/L) and leukocyte (cells/ul). 3- Blood gases study. Different parameters were measured in blood to monitor the blood gases changes. These were, pH (unit), PC02 (mmHg), P02 (mm Hg), and HC03 (m mol/I). The operation was done bycontinuity of the intestinal tract was re-established by a one layerextramucosal end-to- end anastomosis. The isolated segment was folded ina cup patch by U-form technique. Subtotal cystectomy just above the