Mercury exposure of children living in Amazonian villages: influence of geographical location where they lived during prenatal and postnatal development

INTRODUCTION: In some Amazonian river basins, hair mercury concentration is above the recommended levels. We evaluated the influence of birth geographical location in the hair mercury level of Amazonian riverine children. MATERIALS AND METHODS: Hair mercury concentration was measured in 219 children living in four Amazonian riverine communities: Tapajos River (Sao Luiz do Tapajos and Barreiras villages, n = 110), Tocantins River (Limoeiro do Ajuru village, n = 61), and Caete River (Caratateua village, n = 48). We used Poisson regression analysis to evaluate the association between native and non-native children from each village and its hair mercury concentration. RESULTS: Higher mercury exposure was found in native children from Sao Luiz do Tapajos (range = 0.81-22.38 µg/g) followed by native children from Barreiras (range = 0.48-13.46 µg/g), non-native children from Sao Luiz do Tapajos (range = 0.26-22.18 µg/g), non-native children from Barreiras (range = 0.43-20.76 µg/g), followed by the children from Caete and Tocantins river basins. We observed that Tapajos villages' native children had higher prevalence of mercury exposure children than other children (p < 0.05). CONCLUSIONS: Birth geographical location has association to mercury levels in the hair of children who lived in a same community with history of mercury exposure.