Proximity of residence to an old mineral storage site in Chile and blood lead levels in children

Abstract

Evidence suggests that an old mineral storage site removed in 1998 due to high lead content, remains as a source of exposure in the city of Antofagasta, Chile. The aim was to determine the association between blood lead levels in children and the residential proximity to the old mineral storage site. A cross sectional study was conducted with 185 children aged 7 to 16 years. The outcome variable was blood lead levels measured in 2005. The exposure variable was the distance between the current residence and the old mineral storage site. The distance was measured in meters by Geographic Information System (GIS). The median blood lead level in 2005 was 3.3 mu g/dL (interquartile range - IQR: 2.0-4.3). A significant inverse association was found between the residential distance to the old mineral storage site and the blood lead levels in children, after adjusting by confounders (beta: -0.04; 95%CI: -0.09; -0.01). This result suggests that the old mineral storage site continues to be a source of lead exposure for the children living nearby.