ABSENCE OF SYNERGISM BETWEEN EXPOSURE TO ASBESTOS AND CIGARETTE-SMOKING IN ASBESTOSIS

Abstract

To assess independent and synergistic effects of exposure to asbestos and cigarette smoking on the development of asbestosis, survey data from 4 groups of workers exposed to asbestos were analyzed with multivariate statistical models. Survey methods were standardized and included for the 383 subjects a respiratory symptoms questionnaire, occupational history, physical examination, pulmonary function testing, and a chest radiograph. Exposure to asbestos and cigarette smoking were assessed by questionnaire. Synergism between the 2 exposures was not present for previously identified manifestations of asbestosis including bilateral fine crackles, clubbing, dyspnea, radiographic abnormality, decreased forced vital capacity and decreased single-breath diffusing capacity of the lung for CO. Additive, independent effects of these 2 exposures were present for each of these parameters.