Lead exposure is an important environmental health problem particularly affecting the children of occupational workers living in the lead-contaminated environment. The objectives of the study were to find out the frequency, potential sources and adverse health effects of elevated blood lead level (BLL) in the children of lead-related occupational workers. It was a comparative cross-sectional study. A total of two hundred forty six children aged 1-6 years, comprising an equal number (n = 123) from lead smelters/battery recycle plant workers living close to the industries at Wah/Gujranwala, Pakistan (lead-exposed group) and those living 30 km away from the industrial area (controls) were included. Demographic and clinical data of each subject was collected. Blood lead analysis was carried out by using kits on the lead analyzer (3010 B ESA, USA). Biochemical tests of renal and hepatic profile were analyzed on Selectra E auto analyzer. The median age of children was 4 years; comprising of 69 boys and 54 girls. The lead-exposed children had significantly high BLLs median (range) 8.1 (1-20.9) microg/dL as compared to controls 6.7 (1-13.3) microg/dL (p <or= 0.01). The children of occupational workers had elevated BLL (>10 microg/dL) in 38 (31%) as compared with 14 (11%) in controls. Hematopoietic, renal, and hepatic functions were significantly impaired in the lead-exposed children. In conclusion, the children of lead-related occupational workers have significantly increased frequency (31%) of lead poisoning. The potential source of lead overexposure in these children may be indirect through father's clothes and contaminated environment at home. Increased lead accumulation adversely affects health of these children.