Origin, Distribution, and Biogeochemistry of Arsenic in the Altiplano-Puna plateau of South America

TAPIA JOSELINE; NORDSTROM DARRELL KIRK; MURRAY JESICA; TIRADO NOEMI; ORMACHEA MAURICIO

Virtual

Congreso; Goldschmidt 2020; 2020

In South America, the second highest plateau on Earth referred to as the?Altiplano-Puna?, which encompasses areas of Argentina, Bolivia, Chile, and Perú, exhibits high arsenic (As)concentrations in water that could be affecting 3 million inhabitants[1].Themost importantsourcesof As in this region correspond to mineral deposits, hot springs, and volcanic rocks, whereas anthropogenicsources are mining and acidmine drainage (AMD). Asis foundin all water types of the Altiplano-Puna over a wide range of concentrations (0.01 mg/L<As in water> 10 mg/L)which in decreasing order correspond to:AMD, brines, salinewaters, hot springs, rivers affected byAMD, rivers and lakes, and groundwater. Asmobility is highly susceptible to the influence of dry andwet seasons.Few studies report As speciation, in whichAsappearsmostlyin its oxidizedform(As(V)).Asadaptationand efficientmetabolismhas been detectedin some aboriginal communities.However, the inefficient methylation of inorganic As in women might leadto adverse healtheffects such as cancer. Despite the health risks in this As-rich environmentnot all of the Altiplano-Puna is properly characterized and there exists a lack of information regardingthe basic geochemistry of Asin the region.Aninternational and interdisciplinarycollaborative research supported by the IGCP-UNESCO PROJECT 707will investigate specific sites within the Altiplano-Puna to better 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 unusual biodiversity. Human health, the environment, as well as scientific insight will benefit from this research.