Occupational Exposure Risk for Swine Workers in Confined Housing Facilities

Extended exposure of swine barn workers to noise and airborne contaminants has been reported to be associated with various health problems. In this study, the actual exposure of workers to respirable dust, gases (ammonia and hydrogen sulfide), and noise in swine production operations was monitored in order to determine the contribution of specific activities in the barn to potential adverse health impacts to swine workers. Selected workers in a swine barn facility were outfitted with a personal monitoring system that included a respirable dust sampler, ammonia (NH3) and hydrogen sulfide (H2S) gas monitors, and a noise dosimeter as they performed their regular duties during their workday. From a total of 50 monitoring days spanning winter and summer months, results showed that the occupational exposure of swine workers to respirable dust, NH3, H2S, and noise while performing their daily assigned tasks was generally below the respective time-weighted average exposure limits for each hazard. However, a number of tasks showed high likelihood for elevated occupational exposure risk. Respirable dust concentrations exceeded the time-weighted average limit of 3 mg m-3 while feeding and weighing pigs. These activities also exceeded the short-term exposure limit (35 ppm) for NH3. Dangerous levels of H2S were generated when draining manure from manure collection pits in the production rooms. Noise levels exceeded the recommended 15 min exposure limit (100 dBA) when weighing and loading pigs for market. The occupational exposure risks for workers to barn contaminants can be reduced through measures that control the generation of contaminants at their source, by removing generated contaminants from the work environment, as well as by outfitting the workers with protective devices that prevent personal exposure to contaminants.