Exposure of aluminum in the Araçuaí-Itinga Lithium Pegmatite District, Minas Gerais, Brazil: Contamination and toxicological effects on populations established nearby mining activities

Abstract

This study aims to assess the geological, geochemical, and toxicological aspects of aluminum in the Araçuaí-Itinga lithium district, located in the Jequitinhonha River basin, Minas Gerais, with an emphasis on potential health risks for various population groups. Geological investigation revealed a predominance of aluminum-rich granites and metasediments, which serve as source and hosts for lithium--mineralized pegmatites. The study found that lithium levels pose no risk to human health, with maximum concentrations of the order of approximately 0.015 mg/L in water, 78 mg/kg in soil, and 33.7 mg/ kg in stream sediments. However, elevated aluminum levels, where found in over 80% of the studied area, with concentrations exceeding the recommended maximum of 0.1 mg/L. Water samples exhibited aluminum levels ranging from 0.200 and 0.928 mg/L, while concentrations reached 3.1% in soil, and 0.96% in stream sediments. These values highlight the need for for further investigations into potential environmental and human health impacts. Additionally, aluminum concentrations of 1,059 mg/kg were detected in 12 vegetable samples. Plasma analyses of individuals living in the Igrejinha and Fazenda Velha communities revealed aluminum values above the normal limit of 3 µg/L in 68% of the examined individuals, and in 94% of dialysis patients, indicating significant health risks for those undergoing dialysis. The primary route of aluminum for the sampled individuals was water, facilitated by itstransition from rock-to soil-to water-to food. It is estimated that approximately 3,200 people near tributaries of the Jequitinhonha River, particularly in the Valley of Córrego do Piauí, are at risk of aluminum exposure. These findings underscore the urgent need for further research and interventions to mitigate the health risks associated with aluminum exposure in these communities.