Nutrient Composition of Dust Emitted from Poultry Broiler Houses in Northwest Arkansas

Abstract

A substantial body of research has been conducted on the potential water quality impairments associated with land application of poultry broiler litter. However, until recently, little attention has focused on the potential for nutrient runoff from dust emitted from broiler production houses despite related air quality concerns raised by the United States (US) Environmental Protection Agency. The objective of this study was to characterize the composition of broiler house dust (BHD) and compare BHD composition to that of broiler litter (BL). Dust composition varied significantly (P < 0.05) among facilities operated by different integrator companies, likely due to differences in feed and house management among integrators. Specifically, BHD pH was lower (P < 0.05) in Facility 1 than in Facilities 2 and 3, which did not differ, whereas BHD K and Ca were greatest (P < 0.05) in Facility 1 and 2, respectively. The facility average moisture content of BHD was at least 1.9 times lower than that for the BL from the same facility. The facility average total phosphorus (TP) and water extractable phosphorus (WEP) concentrations in BHD were at least 1.2 and 1.6 times greater, respectively, than that for BL from the same facility. The greater WEP in BHD than in BL is of particular environmental importance given that extensive research shows WEP to be a major variable influencing P runoff risk. The facility average total nitrogen (TN) concentration in BHD was at least 3.0 times greater than that for BL from the same facility. As TP, WEP, and TN are greater in BHD than in BL, there is a greater risk of nutrient enrichment of runoff from an equivalent mass of BHD than BL. The results of this study highlight the need for careful management of dust emissions from broiler houses and a need for conservation practices to minimize the risk of BHD increasing nutrient runoff and its loss to waters of the US.

Nutrient Removal Structures Using Locally-Sourced Iron and Aluminum By-Products Reduce Nutrient Runoff from Broiler Production Facilities

“…Concerns have centered on regions with spatially concentrated livestock systems, where nutrients, particularly P, in manure produced exceed local crop requirements, leading to an increased risk of P runoff [10]. For broiler production systems, additional concerns were focused on nutrient runoff from dust deposit adjacent to broiler house ventilation fans [11] [12].…”

“…Accentuating the potential loss of nutrients is the fact that the water solubility of dust P was, on average, three times greater than that in the litter [11]. Strategies to reduce nutrient runoff now target nutrient sources, rather than treating receiving waters, to most effectively decrease impairment [13] [14] [15].…”

Locally Sourced Iron and Aluminum Byproducts Decrease Phosphorus Leached from Broiler House Dust Deposited near Ventilation Fans

“…Prior testing of the RM and WT byproducts [11] showed the hydraulic conductivity of 6-mm-diameter particles of RM was 123 cm 30 min −1 , while that of the 6-mm-diameter particles of WT was 138 cm 30 min Dust collected off fan shutters from four broiler facilities in northwest Arkansas was combined and mixed thoroughly as described by Herron et al [12]. The dust application rate for the experiment was calculated based on direct measurements of dust thicknesses that had settled on the ground adjacent to fan , and 97,600 mg total N kg −1…”

“…Six consecutive dust applications were followed by 30 minutes of simulated rainfall at a rate of 7 cm•hr −1 , the combination of which occurred at one-day intervals. Dust applications approximated the amount of dust deposited on the soil outside a broiler house fan during one year of typical operation (i.e., the production of six flocks of birds; [12]). …”

“…While dust and broiler litter have similar total P concentrations, the impact of P release from ventilation fan dust is exacerbated due to the water solubility of dust P being, on average, three times greater than that in the litter [12]. Removing nutrients from runoff water prior to water leaving the poultry production area is likely the most cost-effective on-farm mitigation practice.…”