Cotton dust and endotoxin exposure-response relationships in cotton textile workers.
Kennedy-SM; Christiani-DC; Eisen-EA; Wegman-DH; Greaves-IA; Olenchock-SA; Ye-T; Lu-L
Am Rev Respir Dis 1987 Jan; 135(1):194-200
A survey of cotton dust and endotoxin response relationships in cotton textile workers was conducted. The cohort consisted of 443 workers in yarn preparation areas of two cotton mills in Shanghai, China. The comparisons consisted of 439 workers from a nearby silk mill who had no previous exposure to cotton dust. Respiratory symptom questionnaires were distributed, and pre and postshift pulmonary function testing was conducted. Area air dust samples were collected in the cotton mills. Forty percent of these were analyzed for endotoxins. Cumulative dust and endotoxin exposures were estimated for each worker. Dose response relationships were studied by stratifying by exposure or using linear and logistic regression models. Dust concentrations were similar in the two mills, ranging from 0.15 to 2.34mg/m3; however, the concentrations varied widely within the work areas of each facility, from 0.31 to 1.83mg/m3. Endotoxin concentrations were 0.02 to 0.92 and 0.002 to widely within different work areas of either facility. Pulmonary function values and prevalence of respiratory symptoms were not correlated with cotton dust concentration. The prevalence of chronic bronchitis and byssinosis increased with increasing endotoxin concentration, except for the highest exposure group. Mean preshift 1 second forced expiratory volume (FEV1) decreased in relation to increased current endotoxin exposure; however, acute changes in FEV1 over a work shift could not be correlated with exposure. Smokers had consistently lower preshift FEV1 values and a greater cross shift decrement than nonsmokers. The prevalence of byssinosis was 6.7 percent among smokers and 8.2 percent among nonsmokers. The authors conclude that their results support the theory that decreased lung function and an increase in symptom prevalence among cotton workers correlate more closely with endotoxin than with cotton dust exposure.
NIOSH-Author; Textile-workers; Occupational-exposure; Plant-dusts; Dose-response; Bacterial-dusts; Microorganisms; Cotton-dust; Occupational-diseases; Pulmonary-system-disorders; Air-sampling
American Review of Respiratory Disease