The relationship between elevated blood metal levels and pneumoconiosis profusion scores and opacity size: a study on foundry workers

Aims: This study aims to describe the demographic, clinical, and radiological characteristics of foundry workers diagnosed with pneumoconiosis and to examine the association between blood metal levels and disease severity, particularly Labour Organization (ILO) pneumoconiosis radiologic profusion and opacity. Methods: A total of 45 foundry workers with radiologically confirmed pneumoconiosis were included. Data on age, smoking history, pulmonary function tests, occupational duration, and working units were collected. Radiological assessment was performed using the International ILO classification. Workers were categorized into two groups based on whole blood metal concentration (normal vs. elevated). Comparative and correlation analyses were conducted. Results: The cohort consisted predominantly of males (97.8%) with a mean age of 50.1 ± 7.8 years and a mean work duration of 18.3 ± 8.9 years. Profusion scores were category 1 in 55.6% and category >1 in 44.4%. Opacity types were mostly small and rounded (type p, 75.6%). A statistically significant inverse correlation was found between blood metal levels and profusion score (r = –0.348, p = 0.019), while profusion and opacity size were positively correlated (r = 0.335, p = 0.025). Work duration and smoking showed no significant association with radiologic severity. Workers in grinding and sandblasting units, despite “normal” blood metal levels, had more advanced radiological findings. Conclusion: Disease severity may not directly correlate with measured blood metal levels but appears influenced by particle type, work unit, and preventive practices. These findings highlight the need for comprehensive occupational risk assessments beyond blood metal biomonitoring.