Freshly generated stainless steel welding fume induces greater lung inflammation in rats as compared to aged fume.
Antonini-JM; Clarke-RW; Krishna Murthy-GG; Sreekanthan-P; Eagar-TW; Brain-JD
Toxicologist 1998 Mar; 42(1-S):348
It has been previously reported that long-lived radicals are present on the surface of freshly generated fumes. The objective of this study was to determine if freshly formed welding fume induces greater lung inflammation and injury in rats due to the presence of reactive oxygen species than aged welding fume. Fume was collected during gas metal arc welding using a stainless steel consumable electrode and found to be of respirable size with a mean diameter of < 2 11. Male CDN AF rats were dosed intratracheally with the welding fume 30 min (FRESH) and 1 and 7 days (AGED) after fume collection at a dose of 1.0 mg/100 g b wt. Bronchoalvcolarlavage (BAL) was performed 24 hr post-instillation. Lung injury and inflammation were assessed by measuring the concentration of neutrophils, albumin, lactate dehydrogenase (LDH), and glucosaminidase (GLU) in the recovered BAL fluid. More neutrophils and enhanced GLU activity were observed for the FRESH group as compared to both AGED groups (p<0.05). Slight, but not significant, elevations were seen in albumin content and LDH activity for the FRESH group as compared to the AGED groups. No significant differences were observed for any of the parameters when fume aged 1 vs. 7 days were compared. When the FRESH and AGED fumes (12.5, 25, and 50 ug/ml) were suspended in dichlorofluorescin (15 uM), a probe which becomes fluorescent when oxidized. the concentration-dependent increases in fluorescence were greater for the FRESH fume vs. the AGED fumes. We have demonstrated that freshly generated welding fume induces greater lung inflammation than AGED fume. This is likely due to increased reactive oxygen species on fresh fume surfaces.
Fumes; Lung-disorders; Lung-disease; Lung-tissue; Lung-irritants; Lung-function; Welders; Welders-lung; Age-factors
The Toxicologist. Society of Toxicology 37th Annual Meeting, March 1-5,1998, Seattle, Washington
Harvard School of Public Health