MICROBIAL ECOLOGY AND SAFETY OF FRESH ON-FARM ORGANICALLY GROWN PRODUCE
Title: Bioaerosols associated with animal production operations
Submitted to: Bioresource Technology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: February 16, 2009
Publication Date: March 26, 2009
Citation: Millner, P.D. 2009. Bioaerosols associated with animal production operations. Bioresource Technology. 100(22):5379-5385.
Interpretive Summary: Livestock and poultry housing units and manure management operations generate airborne particulates (dust), microorganisms, and malodorous vapors. These emissions collectively or individually may cause health symptoms and impacts for farm workers, animals, and some individuals in communities near the farms. This report presents information about the amounts and types of airborne microorganisms, dust, and odorous volatile compounds identified in air inside animal houses. Standardization and validation of the air sample collection devices and analytical methods are identified as a critical need. Limited results are available for bioaerosol emissions during land application of manure either as moist solids and liquid spray systems. Various air dispersion models may be used to predict concentrations of microbes transported off-site. Disinfection of manure liquids is the first option for reducing bioaerosol transport off the field application site. Tank truck application with low-pressure ground-oriented nozzles mitigates off-site bioaerosols, whereas high pressure rotating nozzles with upward discharge trajectories generate large bioaerosol concentrations that sustain viability to off-site locations. Additional research is needed to determine the extent of endotoxin transport off-site during land application of dry solids such as poultry litter. In addition, as different technologies for air or manure management are implemented in various animal production systems, the effects of bioaerosol, endotoxin, dust, and malodorous concentrations on animal productivity, worker health, and community impacts need to be evaluated. The information in the report will be useful to producers, biosystems engineers, microbiologists, industrial hygienists, chemists, and animal scientists concerned with air emissions from animal production operations.
Air emissions from animal housing and manure management operations include a complex mixture of biological, microbial, and inorganic particulates along with odorous volatile compounds. This report highlights the state of current issues, technical knowledge, and remaining challenges to be addressed in evaluating the relationships among airborne microorganisms, dusts, and odorants on animals and workers at animal production facilities and nearby communities. Reports documenting bioaerosol measurements illustrate some of the technical issues related to sample collection, analysis, as well as dispersion and transport to off-farm locations. Approaches to analysis, mitigation and modeling transport are discussed in the context of the risk reduction and management of airborne spread of bioaerosols from animal operations. The need for standardization and validation of bioaerosol collection and analytical techniques for indoor as well as outdoor animal agriculture settings is critical to evaluation of modern animal production systems that are increasingly situated near communities.