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NOTE TO EDITORS: UI researchers presented the findings of this study to the Iowa House Agriculture Committee on Feb. 3. The Associated Press reported the story.

UI researchers study health of neighbors of a large-scale hog operation

IOWA CITY, Iowa -- Neighbors of a large-scale swine operation reported experiencing higher rates of respiratory symptoms, nausea, headaches, and irritation of the eyes, nose and throat, compared to rural residents living near minimal numbers of livestock, according to University of Iowa researchers.

In an article published in the current issue of the Journal of Agricultural Safety and Health, UI researchers detail their findings of a pilot study conducted with 18 people who live within two miles of a 4,000-sow swine production facility. A control group of 18 rural residents who live near minimal livestock also participated in the study. Researchers compared the two groups to identify differences in their self-reported health symptoms.

"This study was in response to the significant number of requests we've received for information on environmental exposures and potential physical and mental health problems related to these facilities," says Dr. Kendall Thu, associate director of Iowa's Center for Agricultural Safety and Health (I-CASH), and a co-author of the research paper. Thu and Dr. Kelley Donham, a co-author of the study and I-CASH director, disclosed the findings to state legislators during testimony before the Iowa House Agriculture Committee on Feb. 3.

UI researchers developed a questionnaire to collect general background information on study participants, as well as their physical and psychological health status. Eighteen physical health symptoms were used, based on previous health status research conducted on swine confinement workers. For example, sputum, cough, shortness of breath, chest tightness and wheezing are symptoms related to inflammation of the bronchioles, the passageways that carry air into the lungs.

Questions about residents' mental health were derived from a Duke University study on mood disorders among neighbors of large swine operations. UI researchers also considered anecdotal information they'd received from people living near large-scale swine facilities -- reports of anxiety, stress and feelings of frustration about the nearby presence of corporate hog farms.

Persons living near a large-scale swine facility reported a higher frequency of 14 of the 18 physical health symptoms used in the study. The results indicated a pattern of four interconnected clusters of symptoms, including respiratory concerns, nausea and weakness, headaches and plugged ears, and irritation of the eyes, nose, and throat. Moreover, each of the symptom clusters have been identified in previous studies as being prevalent among swine facility workers.

Skin rash, muscle aches and fever were reported more frequently among the control group, while reports of hearing problems were equal among both groups.

"What's notable about the results is not necessarily the individual symptoms, or even the clusters of symptoms, but the consistent pattern throughout each of those clusters which, taken together, indicates there may be something going on here," Thu says.

Surprisingly, UI researchers found no evidence to suggest that neighbors of large-scale hog farms had higher rates of anxiety or depression. There was little difference in reported symptoms between the study and control groups.

"Quite frankly, based on previous research, we expected to see psychiatric differences," Donham says.

Study researchers also elicited rural residents' responses to questions about neighborhood social issues, including how well neighbors of a large-scale hog operation knew the owners and operators of the swine facility. Both the study and control groups held the underlying view that owners of such facilities were creating social and class divisions in rural communities. The construction and continuing presence of a large-scale corporate hog operation was viewed as eroding the quality of rural life.

Thu and Donham emphasize that generalizations made from data in this pilot study should be made with caution. The next step for the researchers is to test their findings through a larger study that includes a greater number of swine facilities and neighbors.

"We need to look at a larger population of neighbors and swine confinement workers to get a better sense of what's going on," Thu says. "These issues in Iowa and other states have largely been discussed as an odor or nuisance issue. Our study indicates that it is also relevant to address this issue as a public health concern, and we should look at it in greater detail."

The $15,000 UI study was funded by the UI Center for Health Effects of Environmental Contamination.