Barragens de rejeito de mineração e mortalidade por câncer nos municípios de Minas Gerais

Abstract

Introduction: Mining plays a central role in the economy and history of Minas Gerais, Brazil, and is also socially relevant. However, mining tailings dams represent potential long-term sources of environmental pollution, often containing elements with recognized carcinogenic potential, such as arsenic, beryllium, cadmium, chromium, lead, and nickel. Objective: This study aimed to investigate the association between the geographical proximity of mining tailings dams and cancer mortality rates in municipalities of Minas Gerais (MG), Brazil, from 2010 to 2019. Materials and Methods: This was an ecological study based on secondary data. Outcome variables were total and cause-specific cancer mortality rates, standardized to the Segi world population. The exposure variable was defined as the distance between the municipal seat and the nearest mining dam. Rates were calculated as period averages. Analyses included Lee’s bivariate spatial correlation coefficient (L), global spatial autocorrelation (Moran’s I), and local spatial autocorrelation (LISA). Thematic maps were developed to illustrate the spatial distribution of variables. All analyses were performed in the R environment. Results: Age-standardized cancer mortality rates showed a heterogeneous spatial distribution, with higher rates among men. A negative correlation was observed between the distance from municipal seats to dams and cancer mortality rates, with stronger associations among women. In men, the association was identified only for overall cancer mortality. Spatial analysis revealed high–high clusters of cancer mortality near mining regions. Discussion: Although the observed association was of low magnitude, the findings are consistent with territorial risk patterns and with the literature on chronic effects of exposure to heavy metals. Differences by sex and location highlight the need for studies with greater causal inference potential, such as longitudinal and individual-level investigations, as well as contextual variables in multilevel analyses. Conclusion: The study suggests that proximity to mining dams may be associated with higher cancer mortality rates in Minas Gerais. While causality cannot be established, the findings support the implementation of environmental and health surveillance strategies, as well as the use of social indicators in future analyses.