Accelerated biological aging among chemical plant workers

BACKGROUND: Whether occupational exposures to different chemicals are linked to biological aging remains unclear. We aimed to examine the associations between four occupational chemical exposures-coke oven emissions (COEs), benzene, methanol, or coal dust-and accelerated biological aging in workers. METHODS: We recruited 2621 workers from a chemical plant in Pingdingshan, Henan, China. Occupational exposure was classified by work department and job position, with frontline workers assigned to exposure groups and administrative staff as controls. Specifically, 838 workers were exposed to COEs, 379 to benzene, 180 to methanol, and 799 to coal dust, forming four independent exposure groups, alongside 425 controls. Using the Klemera and Doubal method (KDM), four biological age (BA) metrics and BA accelerations (KDM-BAacc, immuneBAacc, cardio-metabolismBAacc, and liver-kidneyBAacc) were calculated based on 10 biomedical indicators. General linear regression models were used to examine the associations. RESULTS: Exposure to COEs, benzene, and coal dust increased KDM-BAacc by 0.42 years (95 % CI: 0.22-0.62), 0.40 years (0.15-0.65), and 0.34 years (0.11-0.56), respectively, and cardio-metabolismBAacc by 0.37 years (0.19-0.56), 0.35 years (0.13-0.57), and 0.32 years (0.12-0.52), compared to controls. Age-stratified analyses showed these associations were significant only in participants aged 18-44 years (p < 0.05). Additionally, gender-specific analyses indicated that the significant associations of exposures to COEs, benzene, and coal dust with elevated KDM-BAacc, cardio-metabolismBAacc, and liver-kidneyBAacc were more pronounced in females (p < 0.05). Additionally, a significant interaction between gender and COEs exposure was observed (p < 0.05). CONCLUSIONS: Exposure to COEs, benzene, and coal dust may accelerate biological aging in occupational workers, primarily affecting cardiovascular and metabolic systems. These findings underscore the need for stricter occupational safety and regular health monitoring in high-risk industries to prevent premature aging and improve long-term health.