Indigenous communities living near oil exploration sites in the Peruvian Amazon have high levels of mercury, cadmium and lead in their bodies. This is the conclusion of a study led by Cristina O'Callaghan Gordo, a researcher at the Barcelona Institute for Global Health (ISGlobal). She is also a professor in the Faculty of Health Sciences at the Universitat Oberta de Catalunya (UOC) and co-director of the Interuniversity Master's Degree in Planetary Health (UOC, ISGlobal and Pompeu Fabra University).