ToxSci Advance Access originally published online on September 29, 2004
Toxicological Sciences 2004 82(2):608-613; doi:10.1093/toxsci/kfh289
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Toxicological Sciences vol. 82 no. 2 © Society of Toxicology 2004; all rights reserved.
Recovery from Welding-Fume-Exposure-Induced Lung Fibrosis and Pulmonary Function Changes in Sprague Dawley Rats
* Center for Occupational Toxicology, Occupational Safety & Health Research Institute, Daejeon, 305–380, Korea; Department of Environmental Engineering, Yonsei University, Wonju, Korea; College of Veterinary Medicine, Seoul National University, Seoul, Korea; and Department of Preventive Medicine, Kosin University, Pusan, Korea
Received July 7, 2004; accepted September 22, 2004
Welder's pneumoconiosis has generally been determined as benign based on the absence of pulmonary function abnormalities in welders with marked radiographic abnormalities. Yet, there have also been several reports on welders with respiratory symptoms, indicating lung function impairment, X-ray abnormalities, and extensive fibrosis. Accordingly, this study attempted to investigate the inflammatory responses and pulmonary function changes in rats during a 60-day welding-fume-inhalation exposure period to elucidate the process of fibrosis. The rats were exposed to manual metal-arc stainless-steel welding fumes (MMA-SS) with total suspended particulate concentrations of 64.8 ± 0.9 (low dose) and 107.8 ± 2.6 mg/m3 (high dose) for 2 h per day in an inhalation chamber for 60 days. Animals were sacrificed after the initial 2-h exposure and after 15, 30, and 60 days, and the pulmonary function was also measured every week after the daily exposure. Elevated cellular differential counts were also measured in the acellular bronchoalveolar lavage fluid of the rats exposed to the MMA-SS fumes for 60 days. Among the pulmonary function test parameters, only the tidal volume showed a statistically significant and dose-dependent decrease after 35 to 60 days of MMA-SS welding-fume exposure. When the rats exposed to the welding fumes were left for 60 days to recover their lung function and cellular differentiation, recovery was observed in both the high and low-dose rats exposed up to 30 days, resulting in the disappearance of inflammatory cells and restoration of the tidal volume. The rats exposed for 60 days at the low dose also recovered from the inflammation and tidal volume loss, yet the rats exposed for 60 days at the high dose did not fully recover even after a 60-day recovery period. Therefore, when taken together, the results of the current study suggest that a decrease in the tidal volume could be used as an early indicator of pulmonary fibrosis induced by welding-fume exposure in Sprague Dawley rats, and fibrosis would seem to be preventable if the exposure is short-term and moderate.
Key Words: welding fume; pulmonary function test; tidal volume; welder's pneumoconiosis; lung fibrosis.
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  K. T. Rim, K. K. Park, J. H. Sung, Y. H. Chung, J. H. Han, K. S. Cho, K. J. Kim, and I. J. Yu Gene-expression profiling using suppression-subtractive hybridization and cDNA microarray in rat mononuclear cells in response to welding-fume exposure Toxicology and Industrial Health, February 1, 2004; 20(1-5): 77 - 88. [Abstract] [PDF]
|
|