This study evaluates DNA damage and multi-element exposure in populations from La Mojana, a region of North Colombia heavily impacted by artisanal and small-scale gold mining (ASGM). DNA damage markers from the cytokinesis-block micronucleus cytome (CBMN-Cyt) assay, including micronucleated binucleated cells (MNBN), nuclear buds (NBUDs) and nucleoplasmic bridges (NPB), were assessed in 71 exposed individuals and 37 unexposed participants. Exposed individuals had significantly higher MNBN frequencies (PR = 1.26, 95% CI: 1.02-1.57, p = 0.039). Principal Component Analysis (PCA) identified the Soil-Derived Mining-Associated Elements (PC1), including V, Fe, Al, Co, Ba, Se and Mn, as being strongly associated with high MNBN frequencies in the exposed population (PR = 10.45, 95% CI: 9.75-12.18, p < 0.001). GAMLSS modeling revealed non-linear effects of PC1, with greater increases in MNBN at higher concentrations, especially in exposed individuals. These results highlight the dual role of essential and toxic elements, with low concentrations being potentially protective but higher concentrations increasing genotoxicity. Women consistently exhibited higher MNBN frequencies than men, suggesting sex-specific susceptibilities. This study highlights the compounded risks of chronic metal exposure in mining-impacted regions and underscores the urgent need for targeted interventions to mitigate genotoxic risks in vulnerable populations.
Superfund sites are where soil, air, and water are polluted with hazardous materials. Individuals residing and working in these areas are often exposed to metals and other hazardous materials, leading to many adverse health outcomes, including cancer. While individuals are often exposed to multiple chemicals simultaneously, the combined effect of such exposures remains largely unexplored. Here, we investigated the toxicity of metal mixtures in five categories of in vitro assays measuring cytotoxicity, oxidative stress, genotoxicity, cytokine release, and angiogenesis. After testing these mixtures in primary cells and cell lines, we discovered that the nickel/arsenic/cadmium and beryllium/arsenic/cadmium combinations exhibited higher cytotoxicity than their individual compounds, suggesting that the mixtures amplified the cytotoxic effect. To investigate the mechanism underlying their toxicity, we evaluated metal-induced oxidative stress, as oxidative stress is a common factor in most metal-related toxicities. Our results showed that cadmium-induced oxidative stress was increased in mixtures. Some mixtures that induced oxidative stress further increased DNA damage, inhibited DNA synthesis, and activated p53. In addition, some mixtures significantly increased interleukin-8 secretion and angiogenesis more than their component compounds. Our findings offer important insights into metal-related toxicity at Superfund sites.