Effects of welding fumes on lung injury and inflammation: the possible role of free radical production.
Taylor-MD; Lewis-AB; Roberts-JR; Leonard-SS; Shi-X; Antonini-JM
Toxicologist 2002 Mar; 66(1-S):193
The goals of this study were to examine lung damage and inflammation as well as free radical production caused by welding fumes of different composition. Fume was collected during flux-covered manual metal arc welding using a stainless steel consumable electrode (MMA-SS) and gas metal arc welding using a mild steel electrode (GMA-MS) or a stainless steel electrode (GMA-SS). Metal composition analysis by energy dispersive spectroscopy revealed that only MMA-SS was highly soluble, containing both soluble Cr and Mn, while GMA-MS and GMA-SS were relatively insoluble. Using electron spin resonance, hydroxyl radicals were observed in a suspension of MMA-SS fume containing hydrogen peroxide. Both GMA fumes showed no evidence of free radical production. To examine the effects of the fumes on lung damage and inflammation, male Sprague-Dawley rats were intratracheally instilled with either a welding fume suspension at 2 mg/rat or the saline vehicle. On day 3, the right lung was assayed for lipid peroxidation (LPO) products while the left lobes were subjected to bronchoalveolar lavage (BAL). LPO products were elevated in the lungs following MMA-SS treatment only, implicating possible oxidative damage. All fumes caused increases in BAL cell number, including elevated macrophage and neutrophil recovery. However, only MMA-SS led to an increased recovery of eosinophils, indicating a possible immune reaction. MMA-SS treatment caused an elevation of albumin in the first BAL fraction, indicating damage to the alveolar-capillary barrier, while all fumes produced an increase in lactate dehydrogenase activity in that fraction. Total protein in the first BAL fraction was most elevated following MMA-SS treatment. These findings indicate that different welding fumes caused varied responses in the lungs of rats, and that these responses may be correlated to the soluble metal composition of the fume and the ability of the fume to produce free radicals.
Welders-lung; Lung-irritants; Free-radicals; Fumes; Arc-welding; Lung-burden; Immune-reaction; Pulmonary-system-disorders; Respiratory-system-disorders; Laboratory-animals; Animal-studies; In-vivo-study
Work Environment and Workforce: Mixed Exposures
The Toxicologist. Society of Toxicology 41st Annual Meeting and ToxExpo, March 17-21, 2002, Nashville, Tennessee