Blood mercury concentrations in preschool children and potential risk factors in São Paulo, Brazil.

Environmental exposure of preschool children to mercury can elevate blood mercury levels (BML) and negatively affect their health. This study aimed to determine BML in preschool children from Brazil's largest city and explore potential associated risk factors. Blood samples were collected in 2013 from 2436 children (age 1-5 years) attending 50 daycare centers (DCC) located in São Paulo, Brazil.