Arsenic (As) is one of the most prevalent geogenic trace elements in the groundwater environment that presents a worldwide health concern. In South America, the “Altiplano-Puna” plateau exhibits high As concentrations in water that could be affecting 3 million inhabitants from Argentina, Bolivia, Chile, and Perú. In this As-rich environment with limited water resources, there exists a lack of knowledge regarding the basic geochemistry of As, water quality characterization, and affected population and biodiversity. Between 2020-2022 we performed interdisciplinary research to understand (i) the origin of As, (ii) its geochemistry and mobility, (iii) its distribution in the environment, and (iv) its effects in the local community and unique biodiversity. Our research provides new scientific insights into the biogeochemical cycle of As in the environment and its effect on human health and biodiversity. Our dissemination activities increased the visibility of the As issue for the region that had historically received little attention from the scientific community and local authorities. This project led to additional funding and the creation of a solid research network between the South and North hemispheres, fostering the participation of young researchers, students, and women. An extension of the project was obtained to continue our work during 2023.