The main objective of this project is to complete and test an exposure assessment for a textile plant, in which an outbreak of interstitial lung disease of unknown etiology has been described, in an effort to contribute to the search for the cause of disease. Available data for this study include air sampling results, detailed job histories, symptom questionnaire results from a NIOSH HHE, and clinical data. These data will be used to construct a job exposure matrix and to assign values for each of six different exposure metrics to each member of a previously described study cohort. Exposure metrics will include ever/never in each job category, duration in each job category, ever/never having had peak exposure, duration of exposure to peaks, cumulative total dust exposure, and cumulative respirable dust exposure. These exposures will then be used in two different epidemiologic analyses using two different study populations within the investigated facility. One population will include all workers for whom a completed NIOSH questionnaire is available (n=116) and disease will be defined as any worker with cough and shortness of breath beginning while employed at the studied facility and lasting for greater than two months without physician diagnosis of obstructive lung disease. The other will include all workers who had high resolution computerized tomography (HRCT) of the lungs and disease will be defined as any worker with a finding or either diffuse ground glass opacity or micronodularity on HRCT. Odds ratios will be calculated for each exposure metric in each analysis and will be compared between analyses. Differentiation of exposure metrics resulting in strong exposure-response relationships from those with none will help guide future investigations of respiratory morbidity in flocking plants.
