Workers filled out respiratory questionnaires and underwent spirometry tests at their plants at baseline with follow-up every one to two years over a five-year period. Initial total IgE was measured in a 20 percent sample to determine its ability to detect longitudinal changes in lung function and whether it mediated immunoreactivity. In workers exposed to chemical spills, a determination was made if short-term, high level chemical exposure without lung injury or short-term, high level chemical exposure with lung injury affects lung function longitudinally or affects the acquisition of respiratory symptoms. In injured workers and a matched control group, spirometry was performed immediately, at two weeks, at six weeks, and at one year after the episode. In the week after an acute injury, circulating biochemical indications of cell and tissue injury were measured. Total and specified IgE were measured after injury and compared to baseline measurements.