Pulmonary responses to welding fumes: role of metal constituents.
Antonini-JM; Taylor-MD; Zimmer-AT; Roberts-JR
J Toxicol Environ Health, A 2004 Jun; 67(3):233-249
It is estimated that more than one million workers worldwide perform some type of welding as part of their work duties. Epidemiology studies have shown that a large number of welders experience some type of respiratory illness. Respiratory effects seen in full-time welders have included bronchitis, airway irritation, lung function changes, and a possible increase in the incidence of lung cancer. Pulmonary infections are increased in terms of severity, duration, and frequency among welders. Inhalation exposure to welding fumes may vary due to differences in materials used and methods employed. The chemical properties of welding fumes can be quite complex. Most welding materials are alloy mixtures of metals characterized by different steels that may contain iron, manganese, silica, chromium, nickel, zinc, and fluorides. Animal studies have indicated that the presence and combination of different metal constituents is an important determinant in the potential pneumotoxic responses associated with welding fumes. Animal models have demonstrated that stainless steel welding fumes which contain significant levels of nickel and chromium induce more lung injury and inflammation and are retained in the lungs longer than mild steel welding fumes which contain mostly iron. In addition, stainless steel fumes generated from welding processes using fluxes to protect the resulting weld contain elevated levels of soluble metals. These soluble welding fumes have been shown to suppress lung macrophage function and significantly slow the clearance of bacterial pathogens from the lungs after infection. The presence of soluble metals, such as Cr, Ni, and Mn, and the complexes formed by these different metals, as well as fluoride compounds present in fluxes, are likely important in the pulmonary responses observed after welding fume inhalation.
Pulmonary-system; Welding; Fumes; Metals; Workers; Epidemiology; Respiratory-system-disorders; Lung-cancer; Lung-disease; Pulmonary-system-disorders; Animal-studies; Animals; Models; Laboratory-animals; Inhalation-studies
Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, West Virginia, USA
7439-96-5; 7631-86-9; 7440-47-3; 7440-02-0; 7440-66-6
Work Environment and Workforce: Mixed Exposures
Journal of Toxicology and Environmental Health, Part A: Current Issues