Increased mobilization of geogenic arsenic by anthropogenic activities: the Brazilian experience in mining and agricultural areas

Abstract

This review addresses anthropogenic activities related to exploitation and processing of mineral resources containing geogenic arsenic (As) that led to increases in As levels in Brazilian ecosystems. While resuming relevant research concerned with environmental impact assessments derived from mining activities, we also review studies underlining the significance of agriculture on As occurrence from geogenic As sources in Brazil. Although, in general, agroecosystems seem not to be at high risk of As exposure throughout the country, the recent collapse of two iron-ore mining tailing dams, in the Iron Quadrangle, a region with abnormal levels of As of geogenic origin, has raised concerns related to human and environmental threats due to As exposure in these areas. Moreover, we highlight that gold exploration is widespread in the country and yet, human health risk assessments regarding As in most of these areas are still rare. We conclude by emphasizing that long-term environmental monitoring must be conducted to evaluate the real environmental risks of As in Brazilian ecosystems, especially for those affecting people.