What’s behind the alarming rise in birth defects in Brazil’s illegal gold mining capital?

Children await the arrival of other villagers by the banks of the Cururu river, a major tributary of the Tapajós, for the general assembly of Munduruku people at Waro Apompu village, in Pará state. More than 700 Indigenous people from 102 villages attended. Photograph: Fábio Nascimento/Greenpeace

Seven-year-old Valdenisa squealed with delight as she grasped the tape measure above her head. It was part of a game so that a doctor could measure the circumference of her head and check her withered legs.

She was one of a dozen Indigenous Munduruku children being examined by a trio of child neurologists and geneticists earlier this month in Itaituba, in Brazil’s Pará state. Located on the Tapajós River, the town is known as the country’s illegal gold capital, as it accounts for three-quarters of all the illicit gold produced in Brazil.