The relationship between lead mining waste and childhood lead poisoning is poorly understood. This study evaluates the contribution of soil lead to blood lead levels. 125 children between 6 and 71 months of age living in a lead mining area of southwestern Missouri were evaluated for blood lead and their homes tested for lead in soil, dust, and paint. These results were compared to 26 control children. Homes in the lead mining area had significantly increased soil and dust lead levels and significantly higher blood lead levels. The primary source of dust lead was soil lead. There was a strong relationship between blood lead levels and dust, soil, and paint lead. Soil lead related to mining operations plays a significant role in contributing to blood lead levels in children.