CT findings related to exposure to polyvinyl chloride

Abstract

Background Although some adverse health effects of exposure to polyvinyl chloride (PVC) are well known, there is limited evidence of its effects on the respiratory system. Aims To assess the pulmonary effects of exposure to PVC with high-resolution computed tomography (HRCT). Methods Workers and administrative staff of two PVC production plants completed questionnaires and went through pulmonary function testing and HRCT. Analysis of PVC dust in the work environment was performed by the Directorate of Occupational Health and Safety. Results In total, 104 PVC-exposed workers and 43 administrative controls participated. HRCT revealed pleural and/or parenchymal changes in 55% of the exposed subjects. Pleural thickening was detected in 14 subjects, 13 of whom were in the exposed group (P < 0.05). Isolated pleural thickening without parenchymal involvement was present in seven workers, who were all in the exposed group (P < 0.05). Pleural thickening was frequently bilateral and localized to the parietal and visceral pleura. Round opacities, heterogeneous attenuation and ground-glass opacities were only detected in the exposed group (P < 0.05). Exposure to dust increased the risk of findings on HRCT (odds ratio (OR) 4.2, P < 0.05). There were no correlations between pulmonary function tests or respiratory symptoms and HRCT findings. HRCT changes were more common in subjects with forced mid-expiratory flow (FEF25-75) < 50% (P < 0.001). Conclusions This study found that exposure to PVC dust, at levels below the legal limit for respirable particulate matter, was associated with parenchymal changes and pleural thickening on HRCT.