Occupational Exposure to Lead, Cadmium, and Chromium among Welders in Al-Najaf, Iraq: Blood Levels and Associated Health Outcomes: A Cross-Sectional Comparative Study

Background: Welding fumes contain toxic heavy metals such as lead, cadmium, and chromium that may cause oxidative stress, hepatic dysfunction, and other adverse health effects following long-term exposure. The objectives were to compare blood levels of lead, cadmium, and chromium between welders and non-welders. Methods: A comparative cross-sectional study included 100 adult men (20-60 years): 50 welders with ≥1 year of welding-fume exposure and 50 controls. Data were collected using a questionnaire, blood heavy metal measurements by atomic absorption spectrophotometry, and liver function tests. Data were analyzed using SPSS version 29, with p ≤ 0.05 considered statistically significant. Results: Welders had significantly higher levels of Pb (96% vs. 10%), Cd (100% vs. 22%), and Cr (54% vs. 18%) than controls (p ≤ 0.001). Diastolic hypertension (66% vs. 56%, p = 0.02), prediabetes (56% vs. 12%, p ≤ 0.001), elevated AST (32% vs. 2%, p ≤ 0.001) and hyperbilirubinemia (Elevated + High bilirubin categories combined: 74% vs. 42%) were also more common among welders. In addition, respiratory and neurological symptoms were significantly more frequent in welders than in non-welders. Conclusion: Welders had significantly higher blood levels of lead, cadmium, and chromium, which were associated with adverse cardiometabolic outcomes and possible subclinical liver effects. These findings emphasize the importance of improved occupational safety and regular biological monitoring.