Odor and Nutrient Management Newsletter

Spring 2002

Report addresses animal production and air quality concerns

by Gerald Miller, College of Agriculture

A new report addresses public health and environmental concerns about air emissions from concentrated animal feeding operations (CAFOs). The report, which was requested by State of Iowa government officials, was written by faculty members at Iowa State University (ISU) and the University of Iowa (UI).

The report was delivered in early February to the Iowa Department of Natural Resources (DNR), which had charged the universities to consider whether there was scientific evidence for establishing standards for air quality. Also, the DNR asked the universities to address other science-based issues regarding CAFOs.

The report's recommendations are based upon the best science available to ensure that rural air is as free of risk as possible to protect public health, ensure quality of life for rural areas, preserve the environment for all Iowans, and sustain the highly valued Iowa livestock industry, which is a key part of the state economy. The report's recommendations were generated to provide guidance to the DNR and the Environmental Protection Commission, the group that oversees the DNR. The study group hopes the report will provide a sound basis for developing appropriate action by state officials that promote confidence in agricultural production and quality of life in rural Iowa.

What are the recommendations?

  • Air-quality standards should be developed to regulate concentrations of hydrogen sulfide and ammonia. The study group suggested standards for specific levels of hydrogen sulfide and ammonia concentrations at both the property line and at a residence or public use area. The team offered two opinions on odor regulations. One stated that specific regulations should be developed. The other stated that before regulations can be set, more data must be gathered on odor concentrations and their potential link to reported health effects.
  • The study group outlined policy strategies to help improve the siting of future confinement facilities.
  • A number of technologies and management methods currently are available to control emissions. The study group outlined technologies related to housing ventilation, manure storage, and manure applications to land. ISU has conducted research and demonstrations on many of the technologies, some of which have shown dramatic results. There is a particularly strong case to be made on reducing odors through appropriate land-application methods, for example, incorporation of manure within 1 hour of application.

Photo: Aerator on lagoon
Photo: Aerator on lagoon

In making its recommendations, the study group was asked to review scientific evidence of human disease related to CAFOs. Although stating that no specific diseases among community residents can be linked to air emissions from CAFOs, the report outlined some evidence that suggests emissions may constitute a public health hazard, and that precautions should be taken to minimize exposures from CAFOs.

Beginning last summer, ISU's College of Agriculture and UI's College of Public Health assembled the study group of faculty to begin a comprehensive review of scientific information on CAFO issues. The study group consisted of 27 scientists who represented many disciplines, including animal science, veterinary medicine, agricultural engineering, environmental health, civil and environmental engineering, sociology, and economics. Before it was submitted to the DNR, the team's report was reviewed by independent national and international scientists. After release of the report, producers posed a series of questions. Examples of questions ask include the following:

Q. Does the report imply local control for siting CAFOs?

A. No. The study group recommends guidelines be developed based on siting and spatial planning considerations to include local physical factors and weather conditions.

Q. How practical will it be for farmers to notify IDNR before applying manure?

A. The study group agreed most farmers already practice a "good neighbor" policy before applying manure. Notification of DNR was recommended for those situations when farmers would anticipate exceeding hydrogen sulfide and ammonia concentration standards proposed by the study group. Furthermore, exceedance allowances and notification are part of the process that is appropriately addressed by state officials and rule-makers.

Q. How effective are the proposed available technologies for reducing air emissions?

A. ISU scientists have studied a series of alternative technologies and management practices for reducing air emissions from housing units, storage units, and land application. Results of these studies suggest that emissions can be reduced from 50 to 90 percent, depending on the specific strategy implemented.

The study group's 10-chapter report, including the executive summary, is available at www.extension.iastate.edu/airquality/

For a printed publication, call (319) 335-9647 or send an e-mail to debra-venzke@uiowa.edu

return to Odor and Nutrient Management Home Page
This newsletter provides information on manure management, events, regulatory updates, and access to resources

Iowa State University ExtensionAmes, Iowa 50011

Copyright © 1997-2004, Iowa State University. All rights reserved.
Non-Discrimination Statement and Information Disclosures

|Search all contents|

|Odor and Nutrient Management Home Page| |Iowa State University Extension|
|Feedback/Comments to Angela Rieck-Hinz| |Comments on web site|

Page last updated October 5, 2004

Iowa Manure Matters: Odor and Nutrient Management is published by Iowa State University Extension, with funding support from the USDA Natural Resource Conservation Service through Cooperative Agreement No. 74-6114-8-22. To subscribe or change the address of a current subscription, write to Angela Rieck-Hinz, 2104 Agronomy Hall, Iowa State University, Ames, Iowa, 50011-1010 or call 515-294-9590, fax 515-294-9985 or email: amrieck@iastate.edu. Please indicate you are inquiring about the Odor and Nutrient Management Newsletter. The newsletter's coordinators are Angela Rieck-Hinz, extension program specialist, Department of Agronomy, Wendy Powers, environmental extension specialist, Department of Animal Science, and Robert Burns, Department of Agricultural and Biosystems Engineering; the editor is Jean McGuire, the subscription manager is Rachel Klein, the production designer is Beth Kroeschell, and the web page designer is Liisa Jarvinen.

... and justice for all.
The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs and activities on the basis of race, color, national origin, gender, religion, age, disability, political beliefs, sexual orientation, and marital or family status. (Not all prohibited bases apply to all programs.) Many materials can be made available in alternative formats for ADA clients. To file a complaint of discrimination, write USDA, Office of Civil Rights, Room 326-W, Whitten Building, 14th and Independence Avenue, SW, Washington, DC 20250-9410 or call 202-720-5964.