ARS | Publication request: Influence of feedyards on bioaerosols of two small towns on the Southern High Plains

Submitted to: Texas Journal of Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: February 4, 2010
Publication Date: May 1, 2010
Citation: Purdy, C.W., Rice, W.C., Clark, R.N., Straus, D.C. 2010. Influence of feedyards on bioaerosols of two small towns on the Southern High Plains. Texas Journal of Science. 62(2):83-110.

Interpretive Summary: Air quality is affected by aerosolized particulates suspended in the air and these particulates may affect our health. Specific particulate standards have been set by the Environmental Protection Agency (EPA) and these standards must be addressed by all areas of the United States. Aerosol research has mainly been conducted in large cities where heavy industry and combustible engines have been identified as generators of particulate pollution which can be harmful to our health. Very little research has been invested in determining air quality in rural cities and smaller communities, and what agricultural practices may contribute to the generation of aerosolized particulates. We wanted to compare aerosolized bacteria and fungi, the size of aerosolized particles and their concentrations between two small towns on the Southern High Plains. It was determined that City 1 had two times more smaller particles (16.48 ug/m**3 of air) at three locations monitored than City 2 (7.22 ug/m**3 of air). The apparent generators for the increased small particles were many feedyards located in and around City 1. These smaller particles do not settle out; however, the concentrations were well within the EPA standards. This increase in small respirable particles would be important to those people with existing respiratory ailments who need air with as little pollution as possible and to industry which produce products susceptible to the deleterious effect of small aerosolized particles.

Technical Abstract: Aerosol particulates and bioaerosols were compared between two small cities located in the Southern High Plains. Aerosol particulate generators in rural communities have not been well studied. City 1 had many feedyards located in and near it and City 2 had one feedyard located beyond the air sampling area. Two sites were located in each of the two cities, and one farm was located downwind of each city. The sites were monitored non-concurrently in the fall season. Aerosol particulates were monitored by using PM2.5 and PM10 gravimetric monitors, two cyclones air samplers, two laser aerosol monitors, 6 biological cascade impactors, and a weather station. There were significantly (P < 0.0001) higher mean concentrations of PM2.5 particulates for City 1 (16.48 ±1.3 ug/m**3 of air) compared to City 2 (7.22 ± 0.7 µg/m**3 of air). There were no significant differences in PM10 concentrations between the two cities (City 1, 29.97 ±2.7 ug/m**3 of air and City 2, 31.63 ±1.7 ug/m**3 of air). The cyclone monitor and laser aerosol monitor data indicated higher total concentration of particulates in City 2 than City 1. City 2 had a significantly (P < 0.0001) higher concentration of total microbes 55.7 ± 3.9 ug/m**3 of air compared to City 1, 33.9 ±2.2 ug/m**3 of air. The maximum windspeed was higher and lasted for a longer duration in City 2 than in City 1. It was concluded that the feedyards probably increased the concentration of PM2.5 particulates in and around City 1