Uncontrolled Occupational Exposure to 1,1-Dichloro-1-Fluoroethane (HCFC-141b) Is Associated With Acute Pulmonary Toxicity

Background: The toxicity of 1,1-dichloro-1-fluoroethane (HCFC-141b), a hydrochlorofluorocarbon (HCFC), is low according to animal studies. However, pulmonary manifestations associated with acute HCFC exposure by inhalation have not been reported as yet in man. We evaluated the pulmonary effects of HCFC-141b inhalation, caused by an accident, in previously healthy individuals. Methods: The subjects in this study were 15 workers in whom unpleasant symptoms developed after inhaling HCFC-141b at work. Clinical manifestations, radiologic findings, and changes in pulmonary function and airway hyperresponsiveness (AHR) over time were assessed, and BAL fluid analyses findings for four subjects were compared with those of four healthy volunteers (control subjects). Results: (1) Cough, shortness of breath, and malaise developed in most patients, but only two patients complained of a sore throat. (2) A high-resolution CT scan of the chest revealed bilateral diffuse ground-glass opacities that were predominant in upper lung zones. (3) The mean (± SD) FVC was 71.4 ± 18.86% predicted, and the mean FEV 1 /FVC ratio was 92.9 ± 4.25%. Eleven patients (73%) showed restrictive ventilatory impairments during the initial tests. FVC gradually improved, and the FEV 1 /FVC ratio gradually decreased with time. (4) AHR was observed in four subjects during the initial tests. (5) BAL fluid samples revealed significantly higher neutrophil counts than those in control subjects. Conclusions: Overexposure to HCFC-141b was associated with parenchymal lung injury that was characterized by ground-glass opacities, elevated BAL neutrophil counts, and restrictive ventilatory impairment. Restrictive impairments improved with time after exposure. 1,1-dichloro-1-fluoroethane pulmonary intoxication