Pi phenotypes and the prevalence of chest symptoms and lung function abnormalities in workers employed in dusty industris.

Epidemiologic surveys were carried out on 1,138 white men employed in sawmills and grain elevator terminals in British Columbia. In addition to the administration of an occupational-health questionnaire and spirometry, Pi phenotype and the concentration of serum alpha1-antitrypsin were determined. Most of the workers (88.8 per cent) had the Pi M phenotype, whereas 8.0 per cent had the MS phenotype, and 2.7 per cent had the MZ phenotype. Very few workers (0.4 per cent) had other phenotypes. No differences were found among the 3 major phenotypes in the prevalence of chest symptoms and lung function abnormalities, even among cigarette smokers. These findings did not indicate that workers have the MZ phenotype with intermediate alpha-1-antitrypsin deficiency are particularly susceptible to the development of chronic obstructive lung disease under the conditions prevailing in these industries.