BACKGROUND In Antofagasta, Chile, lead is gathered in bulk in urban zones, contaminating surrounding schools and houses. OBJECTIVE To verify if the environmental lead exposure results in high blood lead levels in children living near lead storage sites. METHODS Four hundred eighty-six children under 7 years old, living near lead storage sites and 75 children living far away form these sites, were studied. An inquiry was applied and venous blood was drawn. Air, soil and water lead concentrations were also measured. RESULTS Lead geometric mean concentrations in exposed children were 8.7 micrograms/dL and 4.22 micrograms/dL in unexposed children. Forty seven percent of exposed children and no unexposed children had lead levels over 10 micrograms/dL. The distance of dwellings from lead storage sites, their geographic location and their antiquity were significantly associated with high blood lead levels. Multivariate models disclosed that people living in contaminated sites have an odds ratio of 24.9 for high blood lead levels. CONCLUSIONS Environmental lead contamination is significantly associated with high blood lead levels.