Abstract
Aim: Exposure to toxic heavy metals (Cd, Ni, Pb) causes respiratory and cardiovascular conditions, as well as kidney, eye or skin damage. Given the seriousness of the respiratory changes, we analysed the impact of exposure on blood and broncho-alveolar lavage fluid (BALF) oxidative stress markers.
Material/method: 32 metal plating workers were investigated through a complex protocol including clinical examination and exposure/effect markers: urinary β2-microglobulins (B2M); oxidative stress markers: SOD, reduced (GSH) and total glutathione (GST). BALF was collected by bronchoscopy in 28% of subjects.
Results: Workplace cumulative toxic index was 1.4, although air metal salts were below the TLW. 61% of exposed had emphysema, 43% had ENT diseases, and 78% excreted high rates of B2M due to kidney metal-induced damage. In the subgroup of BALF-tested subjects, blood SOD varied inversely with GSH and GST levels (r=-0.698 p<0.05, r=-0.88 p<0.01), while in BALF the same correlations were positive (r=0.81 p<0.01, r=0.75 p<0.05) suggesting a difference in the dynamic of the oxidative imbalance. BALF SOD inversely correlated with the score evaluating the seriousness of respiratory diseases (r=-0.67 p<0.05) and it varied directly with the total service length (r= 0.78 p< 0.05). These facts, along with the positive association of blood SOD with the length of metal exposure (r=0.60) illustrate the likely occupational causality of these changes.
Conclusions: BALF and blood oxidative stress markers could serve as potential early biomarkers of metal-induced pathology. Further studies are needed to identify the most adequate marker for lung injuries and possible links with malignant transformation.
- Copyright ©the authors 2016