Cytotoxic and Genotoxic Effects in Buccal Cells of Sandstone Quarry Workers

Mineral extraction poses significant occupational health risks, particularly from respirable crystalline silica exposure. Sandstone quarrying generates substantial dust, yet evidence of its genotoxic effects remains limited. This study investigated cytogenotoxic damage in sandstone quarry workers from southern Brazil using the buccal micronucleus (MN) cytome assay. Buccal cell samples were collected from 21 male workers occupationally exposed to sandstone dust and 21 unexposed control subjects, and 2000 cells per individual were analyzed for biomarkers of genomic instability, cytokinesis defects, and cytotoxicity. Exposed workers exhibited significantly higher frequencies of MN (2.3 ± 2.8 vs. 0.3 ± 0.5, p = 0.005), nuclear buds (5.0 ± 3.9 vs. 0.9 ± 1.9, p < 0.001), and pyknotic cells (4.5 ± 3.9 vs. 1.9 ± 2.3, p = 0.026) compared with controls, indicating increased genomic instability and cytotoxic damage. Within the exposed group, longer occupational exposure (> 10 years) was associated with higher frequencies of binucleated cells, and a significant positive correlation was observed between exposure duration and binucleated cell frequency. Additionally, workers engaged in sandstone sawing and cutting showed significantly elevated MN frequencies compared with those performing other quarry-related activities. No significant differences were observed according to reported personal protective equipment use. These findings provide evidence that occupational exposure to sandstone quarry dust is associated with cytogenotoxic effects. The results highlight the importance of biomonitoring as an early warning tool and reinforce the need for effective dust control measures and preventive strategies to protect the occupational health of sandstone quarry workers.