An environmental study of poultry confinement buildings was conducted. General air samples were analyzed for ammonia (7664417), carbon-dioxide (124389), carbon-monoxide (630080), hydrogen-sulfide (7783064), nitrogen-dioxide (10102440), nitrogen oxides, methane (74828), mercaptans, formaldehyde (50000), hydrocarbons, total and respirable dust, and airborne bacteria and fungi at three poultry confinement houses in North Carolina. The total and respirable dust samples were assayed for endotoxins. Particle size distributions of the dusts were determined. Ammonia concentrations ranged from 6.0 to 170 parts per million (ppm), average 25ppm. The highest concentrations occurred in an unused, sealed off and unventilated part of one of the buildings. Carbon-dioxide concentrations ranged from 0.05 to 0.10 percent in the buildings. Concentrations of the other chemicals were below the analytical detection limits. Total and respirable dust concentrations averaged 4.4 and 0.24 milligrams per cubic meter (m3), respectively. The particle size distributions in the three buildings were similar and had a mass median aerodynamic diameter of 15 microns. Concentrations of airborne bacteria and fungi averaged 150,000 and 10,000 colony forming units, respectively. Endotoxin concentrations ranged from 0.77 to 61 nanograms (ng)/m3 in total dust and 0.71 to 15ng/m3 in respirable dust. Endotoxin concentrations were highest in particles having mass median aerodynamic diameters less than 3.5 microns. The authors conclude that contaminants in the poultry confinement buildings are generally below current standards and recommendations.