Detection of occult lung impairment in welders by induced sputum particles and breath oxidation

Background: We evaluated particulate matter in combined induced sputum (IS) and oxidation in exhaled breath condensate (EBC) to test whether underlying inflammatory changes are present in asymptomatic welders. Methods: Thirty welders from the Israel Defense Forces exposed to aluminum/iron (Group 1) or to cadmium/chromium/iron/lead/nickel (Group 2, N = 16) and 27 non-exposed administrators were studied. IS was recovered, particle size distribution, hydrogen peroxide and pH were measured, and exhaled breath condensate was collected. Results: Group 2 had a higher % neutrophils than all other participants (P = 0.0001) and a higher % particles >2 μm in diameter (P = 0.0017). Percent particles and years of exposure highly correlated (P = 0.051). All welders EBC samples had higher concentrations of hydrogen peroxide than controls (P = 0.0001). pH was lower only for Group 2 (P = 0.0001). Conclusions: Combined IS and EBC measurements detect underlying inflammation in airways of asymptomatic welders. It emerged that airway inflammation is present in asymptomatic welders, and that the particle burden, inflammatory cells, and level of oxidative stress are a function of the type and the duration of welding.