Exposure of workers to dust and bioaerosol on a poultry farm

Poultry houses are known for generating excessive dust, which originates from bedding materials, fiberglass insulations, feed, dried fecal materials, and feather particles. Dust may contain microorganisms, including endotoxins, fungi, and bacteria, that may affect living things when inhaled. Dust that contains living organisms is referred to as bioaerosol, and its particle size may range from 0.5 to 100 mu m. Respirable dust, which has an aerodynamic diameter of less than or equal to 4 mu m, can travel to and be deposited in the gas-exchange region of the human respiratory system. This is of particular concern because of the greater health hazard that it poses. The concentrations of respirable dust and bioaerosol measured with samplers attached to the workers (worker-exposure concentrations) were more than 3 (0.82 vs. 0.26 mg/m(3)) and one-and-a-half times (58.46 vs. 33.79 cfu/m(3)) higher, respectively, than the concentrations measured with stationary samplers indoors. The respirable dust is still below the permissible exposure limit (5 mg/m(3)) set by the Occupational Safety and Health Administration, but beyond the limit for animal buildings suggested by other researchers.