Assessment of Workers Exposure to Ammonia In Animal Facilities at Walter C. Todd Agricultural Research Center, Nacogdoches, Texas

Poultry, swine, and equine animal facilities are all considered as Concentrated Animal Feeding Operations (CAFOs). All these CAFOs are emission sources of gases and other pollutants which have negative impacts on the environment, human health, and animal health as well. One of those gases is Ammonia (NH3), which is a colorless, highly irritating gas with a pungent, suffocating odor, and if inhaled in high concentrations, it may cause harm to the human body and the function of lungs. Personal exposure to ammonia was assessed for six workers in the three animal facilities: poultry, swine, and equine. Two workers from each facility wore passive badges (Model 584, Assay Technologies, OH) once per day over the sampling days. Eleven microenvironments frequented by the workers (stalls, barns, swine facility’s rooms, broiler houses) were also monitored daily using color dosimeter tubes (Model 810-3DL, Gastec Corp., Japan). The concentrations in the microenvironments were read directly from the dosimeter tubes. An activity log was used to document the workers’ activities and locations during their shifts. A Repeated Measures ANOVA statistical analysis was used to test for the differences among the personal-exposure concentrations

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 µm. Respirable dust, which has an aerodynamic diameter of less than or equal to 4 µm, 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/m3) and one-and-a-half times (58.46 vs. 33.79 cfu/m3) higher, respectively, than the concentrations measured with stationary samplers indoors. The respirable dust is still below the permissible exposure limit (5 mg/m3) set by the Occupational Safety and Health Administration, but beyond the limit for animal buildings suggested by other researchers

Spatial and Temporal Distributions of Dust and Ammonia Concentrations in a Swine Building

Pollutants, especially dust, are rarely uniformly distributed within ventilated air spaces due to non‐uniform flow fields, particle inertia, gravitational settling, and diffusion. Thus, selecting suitable sampling locations for representative sampling is a challenge. The objective of this study was to determine the spatial and temporal distributions of dust and ammonia concentrations(NH3) in a swine building. Results of this study are useful in the design of sampling strategies that require limited sampling locations and in studying pollutant transport. This study was conducted in a commercial swine building in Illinois. The total suspended particulate (TSP) matter and ammonia concentrations were measured at 50 and 30 indoor sampling locations in December and June, respectively. Results showed that the average TSP concentrations ranged from 0.86 to 3.81 mg m‐3 in December and from 0.24 to 1.68 mg m‐3 in June. In December, the dust gradient across the length of the building was more pronounced than along its length. In June, the gradient along the length of the building was more pronounced, resulting in essentially uniform concentration in a cross‐section. The spatial distributions of the TSP concentrations in both December and June were essentially symmetrical about the longitudinal section of the building. The spatial gradient of NH3 concentrations was more pronounced along the length of the building in December, while the spatial distribution was almost uniform in June. These results suggest that the choice of representative sampling locations indoors will vary depending on the air movement in the building, which is dictated by the ventilation scheme

Measurement of Particle Size Distribution in a Swine Building

The majority of the research in animal buildings has been on measured concentrations of contaminants that the workers and animals are exposed to; emission measurements have only gained attention in recent years due to potential federal regulations on air quality emissions from animal feeding operations (AFOs). The contribution of AFOs to ambient PM10 and PM2.5 entails reliable measurement of particle size distribution. The objective of this study was to measure and compare the size distribution of particulate matter (PM) at multiple locations inside and at the exhausts of a wean‐to‐finish commercial swine building. The particle size distribution was measured by collecting total suspended particulate matter on Teflon filters and using Coulter Counter and Horiba LA‐300 analyzers for particle size distribution analyses. Results showed that the mass median diameter (MMD) of swine PM at the exhaust was about 14% lower than the average MMD indoors (26.84 vs. 31.55m), while the geometric standard deviations were about the same (1.85 vs. 1.86). In addition, the average percentage by volume of PM10 indoors was about 8%, while the percentage of PM10 leaving the building was 10%. In terms of the mass concentrations, PM10 indoors ranged from 0.014 to 0.125 mg m‐3, while at the exhaust PM10 ranged from 0.02 to 0.15 mg m‐3. This study will aid in understanding the exposure of workers to particles indoors and in quantifying the contribution of a commercial swine building to emissions of PM10 in the atmosphere

Effectiveness of Plant Species for Removing Atmospheric Ammonia

Six plant species of Yaupon, Eastern red cedar, American holly, Arizona cypress, Arborvitae and Roughleaf dogwood were utilized to determine their effectiveness in the removal of atmospheric ammonia. All species were exposed to three ammonia levels (1, 5 and 10 ppm) in an environmental chamber. Foliar ammonia content was quantified using an enzymatic technique. The effects of exposure to ammonia on the physiological responses (e.g. photosynthetic activity, stomatal conductance, and transpiration rate) of plants in ambient condition were also determined using an open design photosynthetic gas exchange system. Foliar ammonia content was significantly different among the six plant species (p\u3c0.0001) with Eastern red cedar exhibiting the highest content. The physiological responses differed significantly depending on the plant species and the ammonia treatment level. The photosynthetic response of plants to the presence of ammonia was mixed. At low exposure level, all species except Arborvitae had decreased photosynthetic activity, reducing by as much as 44.5% for Yaupon. At the highest concentration, however, Yaupon’s photosynthetic activity improved by about 10%. Exposure to ammonia caused increased stomatal conductance and transpiration rate on American holly and Arizona cypress, making them more susceptible to water loss

Evaluation of Electrostatic Particle Ionization and Biocurtain™ Technologies to Reduce Air Pollutants from Broiler Houses

The continuing growth of poultry production, along with the increasing urbanization of rural areas, is leading to more odor-related complaints from neighboring communities and more scrutiny from policy makers. It is, therefore, in the best interest of poultry producers to look at control methods for abating odors. Previous studies have shown that substantial amounts of volatile and odorous compounds are adsorbed and transported by dust particles. Thus, by reducing the amount of dust emitted from poultry facilities such as broiler houses, odor may be reduced as well. The objective of this study was to evaluate the effectiveness of two commercially available control technologies (BioCurtain™ and electrostatic particle ionization (EPI) system) in reducing the total suspended particulate matter (TSP), particulate matter \u3c10 \u3eμm in diameter (PM10), ammonia (NH3), and hydrogen sulfide (H2S) emitted from a broiler facility in Texas. The study was conducted at a broiler production facility in two identically designed, ventilated, and managed broiler houses where one served as the treatment house and the other, the control. Measurements were done on two consecutive days each in September and December 2010. BioCurtain™ was tested independently on the first day and in combination with and the EPI on the second day. Reductions in the NH3 and H2S emission rates by as much as 8% (1040 vs. 943 g/h for NH3 and 9.2 vs. 8.4 g/h for H2S) and by as much as 43% (396 vs. 227 g/h) for the TSP emission rates were achieved with the BioCurtain ™. The EPI system reduced the NH3, H2S, and TSP emission rates by as much as 17%, 34% and 39%, respectively. Economic analysis showed that operating the automated EPI and BioCurtain™ system for one 14 m wide and 152 m long broiler building housing an average of 23,000 birds will cost $0.06 per bird