CONTACT: DAVE PEDERSEN
283 Medical Laboratories
Iowa City IA 52242
(319) 335-8032; fax (319) 335-8034
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
"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
"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.