Changes in ventilatory function in grain processing and animal feed workers in relation to exposure to organic dust.
OBJECTIVE
The effects of organic dust exposure on the configuration of the maximum expiratory flow volume (MEFV) curve was examined multivariately.


METHODS
Data from 390 male workers in the animal feed industry in The Netherlands were analyzed. A multivariate technique called nonlinear canonical correlation analyses was used to study the relationship between a set of organic dust exposure variables and a set of ventilatory function variables.


RESULTS
The results indicate an almost independent effect of the overall mean organic dust exposure and the number of years of organic dust exposure on ventilatory function. Increasing mean organic dust exposure was associated with a decrease in both forced expiratory volume in 1 s (FEV1.0) and forced vital capacity (FVC) and decreased flows at high lung volumes only. Increasing number of years of dust exposure was associated with a decrease in FEV1.0 and a decrease in flow at all lung volumes, while the FVC seemed relatively constant. These two distinct patterns of reduction in ventilatory function may represent two different pathological processes. Whereas workers with prolonged exposure showed reduced values for all of the MEFV curve variables, except the FVC, those with only a few years of exposure especially showed a decrease in FVC and peak expiratory flow. The effect of current organic dust exposure was more evident for nonsmokers than for ex-smokers and current smokers.


CONCLUSIONS
The major finding of this study was an independent effect of overall mean organic dust exposure and the number of years of organic dust exposure on the MEFV curve.
Tielemans
E
E
Department of Epidemiology and Public Health, University Wageningen, The Netherlands.
Heederik
D
D
van Pelt
W
W
D000328:Adult; D000395:Air Pollutants, Occupational / Q000009:adverse effects*; D000822:Animal Husbandry; D003430:Cross-Sectional Studies; D004391:Dust / Q000009:adverse effects*; D002523:Edible Grain / Q000009:adverse effects; D006801:Humans; D008297:Male; D008449:Maximal Expiratory Flow-Volume Curves; D015999:Multivariate Analysis; D016273:Occupational Exposure / Q000009:adverse effects*; D012129:Respiratory Function Tests; D015656:Respiratory Mechanics / Q000187:drug effects; D012907:Smoking / Q000009:adverse effects; D013997:Time Factors
D000395:Air Pollutants, Occupational; D004391:Dust