A recent trend in livestock production is the use of enclosed or confinement systems for increased economical production of animal protein. Design of these buildings has not considered potential health hazards that exist for agricultural workers. We have been the only research group in the United States to consider human health aspects of confinement feeding, and our preliminary data offers strong evidence that occupational health hazards exist, particularly with respect to the respiratory system. This project consists of epidemiologic, clinical and environmental studies designed to document and characterize the extent that disease occurs in swine confinement workers with particular emphasis on respiratory disease, and to characterize certain parameters of gases and particulates in the work environment to provide data whereby industrial hygiene techniques may be applied to improve the environment. Epidemiological studies will use data collected by mail and personal interview surveys to quantify the exposed population, characterized symptoms, and establish a data base to develop cohorts for the clinical studies. Clinical studies involving 4 separate cohorts, including a cross-sectional, two environmental challenge studies, and a study of severely affected individuals will be performed to identify etiology of and predict symptoms and effects of chronic exposure. Animal studies will be carried out to predict pathological effects on the human respiratory tract. Environmental studies will include characterization of particulates in the work environment, quantitation of trace toxic gases, and measurement of gases evolved from the manure pit under different environment variable. This will be the first in-depth study into health hazards of swine confinement workers; an area that preliminary data suggests there is a hazardous exposure of from between 640,000 to 2,960,000 workers (including women and children).