HOST DETERMINANTS OF CELLULAR AND BIOCHEMICAL-CONSTITUENTS OF BRONCHOALVEOLAR LAVAGE FLUIDS - IMPLICATIONS FOR DESIGN OF EPIDEMIOLOGIC STUDIES

The effects of demographic characteristics, exercise, environmental ex posures, and other host factors on cellular and biochemical constituen ts of human bronchoalveolar lavage (BAL) fluids were investigated by s tudying more than 300 specimens obtained from normal volunteers and as sayed in a single center. The BAL data demonstrated associations with race, smoking, exercise, skin-test reactions, and blood constituents, and weak or no associations with age, sex, pulmonary function tests (P FT), or ambient ozone exposure. The effect of exercise was relatively strong and more clearly characterized than in previous studies. Smokin g effects were similar to those observed in other studies; our ability to study age and ambient ozone effects was greatly limited because of the homogeneity of the population under study. Blood constituents of the subjects also showed an association with level of exercise. Analys is of intraindividual and interindividual variability in BAL constitue nts results suggested that matching, although desirable, is not essent ial for the maintenance of adequate statistical power in BAL studies, so observational studies of the effects from air pollution on BAL flui ds in humans could be effectively conducted using cross-sectional desi gns.