Fall 2004
ISU College of Agriculture active in air quality research and extension
by Gerald Miller, Associate Dean-Extension Programs and Outreach, Director-Agriculture and Natural Resources Extension
One of the most debated and divisive issues facing Iowans today is what should be done about odor and gas emissions from livestock operations. Experience suggests that the best way to reach common ground is to work together. That’s what we in the Iowa State University (ISU) College of Agriculture are doing, both within the College and in partnership with the agriculture industry and government.
Researchers within the College of Agriculture continue to look for ways to reduce odor and gas emissions from livestock operations. ISU Extension specialists work with producers as this research leads to new knowledge. Funding from farm and commodity groups, industry and state and federal government agencies has been vital to these efforts.
In 2003-2004, 24 externally funded projects - ongoing, recently initiated or recently completed - addressed research and extension issues on air quality/odor, animal waste and manure management. The projects are conducted by scientists in the colleges of Agriculture, Veterinary Medicine and Engineering, as well as by ISU Extension.
Three new projects received funding this year. In March 2004, the U.S. Department of Agriculture announced $5.1 million had been awarded to 11 institutions for air-quality research. ISU received nearly $1.4 million of the total and was the only institution to receive more than one award. One project will study the benefits of trees, shrubs and other perennial plants as buffers to reduce odors around poultry and egg production facilities. Another will investigate odor dispersion from swine facilities. A third will investigate dietary strategies to reduce emissions from animal feeding operations.
Another exciting effort at ISU is the opening this fall of a new lab that will allow our researchers to study the impact of diet and animal manure management practices on air emissions. Animals of all species can be fed individually or in groups, with emission measurements collected the same way. It’s the only facility of its kind in the world. Money and in-kind contributions totaling $700,000 came from the ISU College of Agriculture and the Department of Animal Science.
Iowa State University’s research work is being used to help inform public debate on the air quality issue. During the 2004 Iowa legislative session, ISU administrators and scientists provided testimony and analysis to lawmakers on proposed air quality legislation. At each opportunity, it was made clear ISU supports air-quality standards based on the most current science, while protecting public health.
As new emissions data emerged from research studies and from measurements by state agencies, ISU provided new scientific information, analysis and testimony to the Iowa Department of Natural Resources (DNR) and the Environmental Protection Commission (EPC). Most recently, a statement was prepared for the July 19, 2004, meeting of the EPC where a new standard for hydrogen sulfide emissions was proposed.
The commission voted to approve a new benchmark standard for hydrogen sulfide emissions from animal feeding operations. The new standard is 30 parts per billion (ppb) for one hour as a health effects value. Operations exceeding this standard more than seven times in a year would violate the health effects standard (HES). If the HES is violated, the rule says the DNR can develop plans and programs to reduce hydrogen sulfide emissions.
College officials attended the July 19 EPC meeting and provided scientific input. The key point made by ISU representatives at this and other such opportunities is that we strongly encourage following federal guidelines for ambient air quality levels published by the Agency for Toxic Substances and Disease Registry (ATSDR). The mission of the ATSDR, an agency of the U.S. Department of Health and Human Services, is to serve the public by using science-based information and taking responsible public health actions.
ATSDR lists 70 ppb as the maximum level of hydrogen sulfide for an acute continuous exposure that would last from one to 14 days. It places the intermediate continuous exposure maximum at 30 ppb for anywhere from 14 to 364 days.
ISU scientists believe the 30 ppb level is clearly more appropriate than the 15 ppb exposure level previously recommended by DNR and the EPC. But it’s still lower than the ATSDR recommendation and far removed from the levels being found during ongoing monitoring by ISU researchers and DNR personnel. Nevertheless, ISU expressed support for the 30 ppb standard for hydrogen sulfide, which was in line with prior testimony. A copy of the comments submitted by the College can be found on ISU’s Air Quality and Animal Agriculture page at http://www.extension.iastate.edu/airquality/.
This article provides a very brief review of some of the College activities related to air quality. A comprehensive review is online at http://www.extension.iastate.edu/airquality/reports/isuaqsummary.pdf. This four-page review makes it easy to see that working together, we’re making important progress.
