Antibiotics, pain relievers, anti-anxiety medicines, anticonvulsant drugs—any medications humans take eventually make their way into rivers and streams. A new global study found pharmaceuticals in virtually every inhabited part of the world, with some of the highest cumulative concentrations in South America. The study, published in February in the Proceedings of the National Academy of Sciences, involved analysis of samples taken at 1,052 locations along 258 rivers in 104 countries, nine of them in Latin America. The result, the authors said, is a “pharmaceutical fingerprint” of more than 471 million people. Samples were gathered in 36 countries where such studies had never been done, among them Bolivia, Panama, Peru and Uruguay in Latin America and Antigua and Barbuda in the Caribbean. The analysis was designed to detect 61 “active pharmaceutical ingredients,” mainly substances used in medicines, but also caffeine and nicotine. Sampling sites were chosen to reflect a... [Log in to read more]