Headaches, runny noses, sore throats, excessive coughing, diarrhoea and burning eyes were reported more frequently in people living in three rural North Carolina communities near an industrial pig farming operation, according to research published by the University of North Carolina at Chapel Hill (UNC-CH).

Pig farms were also found to reduce their neighbours’ quality of life. The study found that the number of times residents could not open their windows or go outside even in fine weather was greatly increased among residents near the pig farm in comparison to those living in a control community and a community in the vicinity of a cattle farming operation.

Researchers from UNC-CH completed 155 interviews with people living near a 6,000-head pig operation, two adjacent cattle farms and, as a control, a farm area without large livestock operations.

The researchers chose three eastern North Carolina areas with similar economic and social characteristics. They chose sites with 80 to 100 households within a two-mile radius of livestock operations so they could interview people in about 50 households in each community.

Residents of the pig farming community could have reported more symptoms because of their feelings about the negative impact of the hog operation on their community, Dr. Steven Wing, associate professor of epidemiology at the UNC-CH School of Public Health said. However, if that had occurred, researchers would have expected excess reports of most symptoms, not just some.

“In fact, the eight symptoms in the miscellaneous category – none of which were expected to be related to exposure to airborne emissions -occurred with about the same frequency in the hog and control communities,” Wing said. “This suggests that there was not a tendency for over-reporting among residents of the hog community.”

About two-thirds of people questioned by trained interviewers were women. Just over 90 percent were black and most of the rest were white. Average annual family income was about $20,000.

By far the largest differences between the communities were seen in the quality-of-life questions, researchers found. More than half of respondents in the hog community, compared to fewer than a fifth in the other two areas, reported not being able to open windows or go outside even in fine weather 12 or more times over the previous six months.

“Dr. Wing’s research on how hog operations are affecting the health of our communities in eastern North Carolina contributes greatly to our understanding of how large animal operations impact our environment and public health,” said Irene McFarland, staff attorney for the North Carolina Public Interest Research Group.

“While those living near hog operations have long known that their health was being impacted, until Dr. Wing’s study, the affected communities lacked the documentation to prove the extent to which their health has been jeopardised,” McFarland said. “Now that we have data establishing the scope of the harms communities are experiencing we need to take action by enacting stronger laws to protect our health and the environment from agricultural pollution.”

“In North Carolina there are approximately 2,500 intensive hog operations, and they are located disproportionately in areas that are poor and nonwhite,” Wing said. “The public health and environmental injustice implications of this geographical pattern extend beyond the physiologic impact of airborne emissions to issues of well-water contamination and the negative impact of noxious odours on community economic development.”

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