Purpose: To assess changes in oxidative DNA damage and lung function amongst a group of foundry workers resulting from an engineering intervention to reduce air respirable dust in their working environment.
Methods: We studied all 22 workers recruited from a typical small Taiwanese iron foundry plant before and 3 months after improvements to air exhaust control. The effectiveness of the air exhaust intervention in reducing respirable dust and SiO₂ was determined by personal breathing-zone air sampling. Initial baseline biomarker measurements were taken of lung function and urinary 8-hydroxy-deoxyguanosine (8-OHdG) in all of the workers, with follow-up measurements taken 3 months after the engineering control was put in place. Generalized estimating equations were used to assess the effect of the intervention on lung function and oxidative DNA damage.
Results: Following the intervention, respirable dust density decreased from 2.87 ± 1.38 mg/m³ to 1.60 ± 0.70 mg/m³ (p = 0.07), and SiO₂ concentration decreased from 0.43 ± 0.25 mg/m³ to 0.18 ± 0.11 mg/m³ (p < 0.05). Compared to initial baseline, significant improvements were found in lung function (FVC, FEV1, FVC%pred and FEV1%pred) amongst the workers after the engineering intervention. A significant increase in concentration of urinary 8-OHdG was observed after the engineering intervention in smokers, but not in non-smokers.
Conclusions: These findings indicate that reductions in workplace respirable dust and SiO₂ concentration can result in improved lung function amongst foundry workers.