Air Pollution & Odor

General Resources

Air Pollution Factsheet

A collection of facts about CAFO-related air and odor pollution.

Air Quality Factsheet

Facts from an Iowa CAFO Air Quality Study that focuses on the human health effects of exposure to ammonia and hydrogen sulfide emissions from CAFOs.

In the US, 44 of the 50 states have regulations that deal directly or indirectly with odors from concentrated animal feeding operations (CAFOs). This article lists ten states that have direct odor regulations, which means they have specific rules that prohibit odor emissions greater than their standard. (National Hog Farmer, March 2001.)

Odor From Feedlots Setback Estimation Tool (OFFSET)

The result of four years of extensive data collection and field testing. A simple tool designed to help answer basic questions about odor impacts from livestock and poultry facilities.

Recent Research on Antibiotic Resistance and Animal Agriculture

Recent research on airborne and waterborne antibiotic-resistant bacteria and concentrated animal feeding operations. Studies reviewing the levels of airborne antibiotic-resistant pathogens in human habitats downwind from animal confinement facilities and the potential aerial transfer of antibiotic resistance to humans and the environment. Additional research on the danger of pig house dust to farmers and the evolution of antibiotic-resistant genes generated on farms and propagated in the environment through groundwater. (July 2005.)

Hog Farms Pose Risks of Waste Spills and Runoff

Explains the hazards of ammonia rising from hog waste lagoons. (”Airborne Menace,” Stuart Leavenworth and James Eli Shiffer, Sunday Raleigh News and Observer, July 5, 1998.)

Hydrogen Sulfide Resources

The Environment and Factory Farms

The “mist” that permeates the homes and skin of thousands of people who live near factory farms commonly contains dangerous levels of such noxious gases as hydrogen sulfide, ammonia and methane. (In Motion Magazine.)

Hydrogen Sulfide Background & Petition

Petition to EPA to designate hydrogen sulfide as a hazardous air pollutant. Good background on the issue. (Texas Sierra Club, 1999.)

Studies Indicate Hog Farms Hazardous to Health

At least 19 people have died in accidents involving hydrogen sulfide releases in manure pits. In the US, there are no federal standards or regulations for many of the compounds associated with factory farm odors when they are outside, including the toxic gases hydrogen sulfide and ammonia. (EarthVision Reports, December 29, 1998.)

Toxicity, Hydrogen Sulfide

Report on the toxicity of hydrogen sulfide, including its clinical effects and how to treat those exposed to the gas. (Dr. Sujal Mandavia, Emedicine.com, updated May 25, 2001.)

Reports

Airborne Antibiotic Resistant and Non resistant Bacteria and Fungi Recovered from Two Swine Herd Confined Animal Feeding Operations

Antibiotic-resistant organisms known to have adverse human health effects were released from the facilities and recovered both inside and downwind of the facility. People near these facilities could potentially be exposed to large numbers of resistant forms of bacteria. (Shawn Gibbs, Christopher Green, Patrick Tarwater, Pasquale Scarpino, Journal of Occupational and Environmental Hygiene, November, 2004.)

Airborne Multi-drug Resistant Bacteria Isolated from a Concentrated Swine Feeding Operation

This study suggests that the inhalation of air from swine CAFOs may constitute an additional environmental exposure pathway for the transfer of multi-drug-resistant bacterial pathogens from swine to humans. Given the growing interest in reservoirs of antibiotic-resistant genes associated with large-scale livestock operations, the findings of this investigation emphasize the importance of studying multiple genera of bacteria in different environmental media as sources of human exposure to antibiotic-resistant genes. (Johns Hopkins Bloomberg School of Public Health, November, 2004.)

Air Emissions from Animal Feeding Operations: Current Knowledge, Future Needs

An evaluation of the scientific information needed to address the regulation and mitigation of air emissions from factory farms. Includes a review of characteristics of agricultural animal industries, methods for measuring and estimating emissions, and potential best management practices, including costs and technological feasibility. The report identifies critical research needs for the next five years and provides recommendations on science-based approaches for estimating and measuring emissions. (Ad Hoc Committee on Air Emissions from Animal Feeding Operations for the National Research Council of the National Academy of Sciences, 2003.)

Air Pollution Control Officer’s Determination of VOC Emission Factors for Dairies

This report presents the basis for the Air Pollution Control Officer’s determination of volatile organic compound (VOC) emission factors to be used for permitting San Joaquin Valley dairies. The report provides appropriate emission factors for different sources and constituents and makes recommendations for future study and research. (San Joaquin Valley Air Pollution Control District, August 2005.)

Concentrated Animal Feedlot Operations (CAFOs) Chemicals Associated with Air Emissions

After conducting a review of the existing scientific literature concerning air emissions from CAFOs, the CAFO subcommittee of the Michigan Department of Environmental Quality summarized its findings in this report. The document provides an overview of the air pollutants emitted by CAFOs, notes the regulatory levels of chemical concern, and describes the potential impacts of these pollutants on human health. (CAFO subcommittee of the Michigan Department of Environmental Quality (MDEQ) Toxics Steering Group (TSG), May 10, 2006.)

Dairy Odor Management & Control Practices

A basic introduction to odor produced by factory farms – includes information about odor perception, odor measurement, and technologies used to manage odor emissions from factory farms. (Sheffield, Ron, and Robyn Walton, University of Idaho.)

Notes on the 2002 NAS Study: “Air Emissions from Animal Feeding Operations: Current Knowledge, Future Needs”

Synopsis and remarks on the National Academy of Sciences Air Emissions Study (2002 pre-publication version of “Air Emissions from Animal Feeding Operations: Current Knowledge, Future Needs“). A step-by-step guide to aid citizens in deciphering the conclusions of the NAS report, which demonstrates that the entire method currently used to calculate emissions from factory farms is fatally flawed and thus there is no basis for issuing permits for these operations in order to protect public health. (William J. Weida, January 19, 2003.)

Air Pollution from Swine Production Facilities Differing in Waste Management Practice

Gaseous emissions from swine manure storage systems create air quality concerns due to the potential impacts of hydrogen sulfide, ammonia, methane, and volatile organic compounds on environmental quality and human health. Proceedings from the Odors and Emission 2000 Conference. (James Zahn, Jerry Hatfield, Young Do, Alan DiSpirito, National Soil Tilth Laboratory, USDA.)

Air Quality Research and Technology Transfer White Paper and Recommendations for Concentrated Animal Feeding Operations

To continue the US predominance in agricultural production, the USDA Agricultural Air Quality Task Force, established by Congress in the 1996 Farm Bill, recommends an additional $65 million be annually appropriated for agricultural air quality issues, with $12.8 million specifically targeted for CAFO research needs. (Confined Livestock Air Quality Committee of the USDA Agricultural Air Quality Task Force, July 19, 2000.)

Bioaerosol Distribution Patterns Adjacent to Two Swine Growing-Finishing Housed Confinement Units in the American Midwest

A study investigating the presence of microbes in the air from hog CAFOs and the implications for neighboring communities and CAFO workers. [View Summary] (P.V. Scarpino and H. Quinn, University of Cincinnati, 1999.)

Controlling Odor and Gaseous Emission Problems from Industrial Swine Facilities: A Handbook for All Interested Parties

This study by the Yale Environmental Protection Clinic addresses the complex odor issues associated with large-scale swine production in Oklahoma and other states. The timely report gives rural citizens and state leaders a quick, comprehensive education in hog waste. Download PDF of Fall 1998 update to study here. (Spring 1998.)

Controlling Odor and Gaseous Emission Problems from Industrial Swine Facilities: Recent Laws and New Ideas

In this update to last year’s publication by the same name, Yale Environmental Clinic students go beyond analysis of the odor problems associated with industrial swine facilities to discuss economics, clean water, recent court cases, and alternative methods of raising hogs. Included is a description of a Minnesota “hoop house,” an alternative swine production system. (Yale Environmental Protection Clinic, Fall 1998.)

Development and Selection of Ammonia Emission Factors

This report compiles and reviews literature on sources of ammonia emissions, including animal factories. (EC/R Incorporated for the US Environmental Protection Agency, 1994.)

Effect of Lagoon Aeration on Odor Emissions from a Swine Grow-Finish (Executive Summary)

A study of the effect of lagoon aeration on odor emissions from a 6,000 head swine grow-finish facility in Oklahoma. (Albert J. Heber, Ph.D., P.E., Associate Professor, Dept. of Agricultural and Biological Engineering, Purdue University, May 1998.)

Feedlot Air Quality Summary: Data Collection, Enforcement and Program Development

A 46-page study on hydrogen sulfide and ammonia emissions from Minnesota feedlot facilities. (Minnesota Pollution Control Agency, March 1999.)

A Field Study on Downwind Odor Transport from Swine Facilities

This paper presents field data to illustrate the characteristics of downwind odor dispersion. A total of eight swine facilities were studied in this project. Power functions were found to be an appropriate description of the pattern of downwind odor transport for both swine buildings and manure storage lagoons and tanks. It was found that swine buildings have the potential to generate more odor than manure storage facilities such as lagoons and tanks and thus could be the major odor sources causing downwind odor nuisance. (See the report in the Journal of Environmental Science & Health Vol.B35(2): 245-258 (2000) or see the University of Minnesota Southern Research and Outreach Center to contact the author.)

Health Effects of Airborne Exposures from Concentrated Animal Feeding Operations

This scientific workgroup report provides an overview of existing scientific research regarding the health effects of exposure to airborne pollutants emitted by factory farms. (Environmental Health Perspectives, November 2006.)

Health Effects of Breathing Air Near CAFOs for Feeder Cattle or Hogs

This article summarizes the results of existing studies of the health effects caused by exposure to air pollutants emitted by cattle and hog factory farms. (Von Essen, Sussana G., and Auvermann, Brent W. Journal of Agromedicine. Vol. 10 (4). 2005.)

Iowa Concentrated Animal Feeding Operation Air Quality Study

A joint report from a team of scientists at the University of Iowa and Iowa State University that recommends the development of ambient air-quality standards for CAFOs. (University of Iowa, Environmental Health Sciences Research Center, February 2002.)

Isolation of Antibiotic-Resistant Bacteria from the Air Plume Downwind of a Swine Confined or Concentrated Animal Feeding Operation

This study evaluated the levels of antibiotic and multidrug-resistant bacteria in bioaerosols upwind, within, and downwind of a swine confined animal feeding operation. (Environmental Health Perspectives, Vol. 114, Number 7, July 2006.)

Methods and Practices to Reduce Odor from Swine Facilities

Odors, emitted mainly from manure but also from decaying feed and carcasses, are a major concern of the pork industry. Report describes all known methods and practices that may reduce odor nuisance from swine production units. (Albert J. Heber, Don J. Jones, Alan L. Sutton, Purdue University, January 1999.)

Monitoring and Modeling of Emissions from CAFOs: Overview of Methods

This scientific workgroup report describes the instrumentation and plume dispersion modeling techniques currently used to assess contaminant concentration levels near CAFOs. (Environmental Health Perspectives, November 2006.)

Neighbor Health and Large-Scale Swine Production

This paper focuses on emergent agricultural health concerns related to CAFOs, namely public health concerns for neighbors exposed to CAFO emissions. (Kendall M. Thu, Ph.D., March 2001.)

Options for Managing Odor

Report on swine odors with a focus on North Carolina. From the North Carolina Agricultural Research Service, University of NC. (Swine Odor Task Force, March 1995.)

Potential Health Effects of Odor From Animal Operations, Wastewater Treatment, and Recycling of Byproducts (Summary)

A workshop was held at Duke University on April 16-17, 1998 cosponsored by Duke University, the Environmental Protection Agency (EPA), and National Institute on Deafness and Other Communication Disorders (NIDCD) to assess the current state of knowledge regarding the health effects of ambient odors. This report summarizes the conclusions from the workshop regarding the potential mechanisms responsible for health symptoms from ambient odors. Methods for validation of health symptoms, presence of odor, and efficacy of odor management techniques are also described. (Journal of Agromedicine, Vol. 7, number 1, 2000.)

Race, Poverty, and Potential Exposure of Middle-School Students to Air Emissions from Confined Swine Feeding Operations

This study investigates the extent to which public school students may be exposed to airborne effluent from swine CAFOs, and evaluates the association between schools’ demographic characteristics and swine CAFO exposures. Previous studies suggest that airborne effluent from swine confined animal feeding operations (CAFOs) may affect the health and quality of life of adults and the prevalence of asthma symptoms among children. (Environmental Health Perspectives, Vol. 114, Number 4, April 2006.)

Symptomatic Effects of Exposure to Diluted Air Sampled from a Swine Confinement Atmosphere on Healthy Human Subjects

In this study, aerial emissions from a swine house at North Carolina State University’s field laboratory were diluted to a level that could occur at varying distances downwind of a confined animal feeding operation (CAFO) both within and beyond the property line, and these emissions were delivered to an environmental exposure chamber. Headaches, eye irritation and nausea were reported. (Environmental Health Perspectives, May 2005.)

USDA Agricultural Research Service Swine Odor and Manure Management Research Unit

Reports from the USDA. Look at both the publications and the research pages.

The Scientific Basis for Estimating Air Emissions from Animal Feeding Operations

Available for viewing online as well as for purchase. From the Board on Agriculture and Natural Resources (BANR) and the Board on Environmental Studies and Toxicology (BEST). (National Academy Press, 2002.)