Metal exposure in Brazilian children of waste pickers from the largest open garbage dump in Latin America: Use of deciduous teeth as biomarker.

Environmental exposures to metals is a concern for public health, due to their association with various adverse health outcomes, especially in children. The aim of this study was to analyze 21 metals (V, Cr, Mn, Co, Ni, Cu, Zn, As, Se, Rb, Ag, Cd, Ba, Ti, Pb, U, Sn, Mo, Ce, La, and Th) in deciduous teeth of waste pickers' children from an open garbage dump region (Estrutural region- Group 1), and compare them with children living in two other regions in Brasilia (Ceilandia - Group 2, and Plano Piloto - Group 3). Three hundred and two children participated in the study, and a single deciduous whole tooth (dentine plus enamel) was analyzed from each child. Socio-demographic variables, breastfeeding time, visits to the dentist, drinking water consumption, among others, were obtained through a questionnaire provided to the parents or guardians of the children. Metal analyses were performed by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Significantly higher concentrations of V, Co, Cu, and As were found in children from G1, where most parents were waste pickers, compared to the other two regions (p < 0.01). Pb and Cd concentrations were significantly higher in children from G2 and G3 compared with G1 (p < 0.01). Significantly higher levels of Cr, Mn, Zn and Se were found in children from G2 (p < 0.01), where residents also have very low income, analogous to G1. We found a trend towards an increase in metal concentrations in incisor compared to canine and molar teeth of children in all three groups. This study provides novel data and reinforces the use of deciduous teeth as potential matrix for biomonitoring children's metal exposures.