Occupational exposure to antimony from cement additives: Speciation and health risk insights

Antimony (Sb) is an emerging environmental contaminant of concern due to its persistence, bioaccumulation potential, and toxicity. Its trivalent form [Sb(III)] is of particular relevance, as it is classified as a suspected human carcinogen. In the cement industry, Sb-based additives are increasingly used to mitigate water-soluble hexavalent chromium [Cr(VI)], a highly toxic and allergenic compound. However, the environmental fate, chemical speciation, and occupational exposure to Sb during cement handling are still poorly characterized. This study developed and validated a robust analytical workflow combining citric acid-EDTA extraction with HPLC-ICP-MS/MS detection for accurate Sb(III)/Sb(V) differentiation in complex industrial matrices. The method ensured oxidation-state preservation and achieved recovery values up to 68%. The workflow was applied to commercial additives, premixed cements, and personal air filters collected from workers during bagging operations. Sb(III) was identified as the predominant species in both bulk materials and airborne particulate matter. Airborne Sb concentrations ranged from 0.00004 to 0.00114 mg m^-3, remaining below international occupational exposure limits. The predominance of Sb(III) in both bulk materials and airborne particulate matter underscores the importance of chemical speciation in occupational exposure assessment. The validated workflow offers a practical approach for monitoring antimony species in cement production environments and supports evidence-based risk management.