Environmental study of poultry confinement buildings.

Environmental measurements were made in three poultry confinement buildings in order to characterize gas and particulate contaminants. Levels of total and respirable dust averaged 4.4 and 0.24 mg/m3, respectively. Particle size distribution as measured by cascade impactors was similar in the three confinement houses with a mass median aerodynamic diameter of about 15 microns and a geometric standard deviation of about 2.2. Ammonia levels measured in the active areas of the buildings averaged about 25 ppm. Ammonia concentration was quite high, however, in an unused and unventilated portion of one of the buildings (mean = 170 ppm). CO2 levels ranged from 0.05-0.1%. Levels of CO, H2S, NO2, NOx, CH4, mercaptan, formaldehyde, and hydrocarbons were all below the limit of detection for indicator tubes. Concentrations of airborne bacteria and fungi were on average about 1.5 X 10(5) and 1.0 X 10(4) colony-forming units/m3, respectively. Endotoxin analysis was also performed on the total and respirable dust samples. Endotoxin levels (expressed in air concentration) ranged from 0.77 to 61 ng/m3 for total dust and from 0.71 to 15 ng/m3 for respirable dust. Endotoxin was also measured on the collection media from the individual impactor stages. Endotoxin was detected in all size ranges with the highest concentration of endotoxin per unit of dust found in the smallest (less than approximately 3.5 microns) size fraction. The endotoxin levels tend to be lower than those previously reported in poultry operations.