A study in the US has found that more than 500 kilometres of Peru's Amazon River is contaminated with mercury.
For decades, illegal gold miners have been pouring thousands of tons of mercury into rivers. Peruvian officials now say nearly 50 thousand people, or 50 percent of the population of Madre de Dios may be affected. In May the government declared a state of emergency.
Al Jazeera’s Mariana Sanchez reports from Madre de Dios, Peru.