Giant pig farms: Antibiotic resistance is not the only problem

When I talk about farming, I usually focus on antibiotic over-use and the way that it stimulates the emergence of drug-resistant organisms. That’s part of what my recent book is about, and to me, it’s the critical piece in the entire discussion of industrial-scale agriculture. If we didn’t use antibiotics in such vast quantities, confined animal-feeding operations, CAFOS, couldn’t exist: Animals couldn’t survive in those conditions without them.

But so many other negatives come from CAFOs — not just antibiotic resistance, but air and water contamination, and chronic human diseases caused by effluent and pollution. I’m grateful to be reminded of that via a webinar hosted this afternoon by the Institute for Agriculture and Trade Policy, which threw a sharp light on the impact of industrial-scale hog farming in North Carolina.

The webinar took a close look at new research by University of North Carolina associate professor Steven Wing. His paper, just published on the website of the journal Epidemiology, details the acute physical symptoms experienced by North Carolina residents who live in areas near very large hog farms: eye irritation, wheezing, chest tightness, shortness of breath, sore throat and nausea.

Emerging from the farms, Wing said, are “dust, and particles from dried feces, as well as spraying of waste that aerosolizes that material. There are several important gases such as ammonia and hydrogen sulfide… as well as bioaerosols, which include endotoxin from dead bacteria. Some of these materials… are allergenic and can cause respiratory problems.”

(See Wing’s image above of manure spraying, and dead-pig disposal, outside a North Carolina hog farm.)

To get that data, Wing and colleagues at UNC and Mount Sinai School of Medicine collaborated with residents of eastern North Carolina, especially the Concerned Citizens of Tillery, in a project dubbed Community Health Effects of Industrial Hog Operations (CHIEHO). They recruited 101 adults in 16 communities who agreed to sit outside for 10 minutes twice a day, every day for two weeks, and to log their symptoms and also measure their lung function with a flow meter. Separately, the team measured ambient air pollution with continuous monitors that were parked in each community.

Overall, between September 2003 and 2005, they received 2,900 responses about people’s symptoms in the previous 12 hours, 2,600 about symptoms that were provoked by those episodes of sitting outdoors, and 1,900 error-free measurements of lung function. And — no surprise for anyone who knows what these farms look like and smell like — the symptoms tracked with the air pollution measurements.

Wing asked: “Is it fair to tell anyone they can’t go outside their own home because it is too polluted to be there?”

Here’s why conditions outside those eastern North Carolina houses are so bad. Within two miles of each of the communities that contributed to the research, there was an average of 42,000 hogs. Within North Carolina as a whole, there are more than 10 million hogs on more than 2,400 farms. The distribution looks like this:

The spots where the dots cluster most densely are Duplin and Sampson counties. Duplin contains 45 hogs for every resident; Sampson, 32. Something else those areas have in common, mentioned during the webinar by Naeema Muhammad, from Concerned Citizens of Tillery:

Most of those operations are in eastern North Carolina, and eastern North Carolina is where you have your predominantly African-American communities, …other communities of color and also your highest rates of poverty. Looking at that map, we are able to use the phrase “environmental racism.”

Wing and colleagues add in their paper:

…in low-income communities of color… there is more potential for exposure to outdoor air pollutants due to older homes that are not air tight and have no air conditioning. Many residents also lack the financial resources to travel and choose activities that could help them avoid high pollution. Exposure to air pollution from hog operations is an environmental injustice in rural areas hosting facilities that supply pork to populations spared the burdens of its production.

IATP said today they will subsequently post a recording of the webinar along with its slides; I’ll update when it goes live.

Cite: Schinasi, L et al. Air Pollution, Lung Function, and Physical Symptoms in Communities Near Concentrated Swine Feeding Operations. Epidemiology 2011;22: 208–215. DOI: 10.1097/EDE.0b013e3182093c8b

Images: Dead pigs and manure spraying at a North Carolina farm/Institute for Agriculture and Trade Policy + S. Wing, UNC; map of North Carolina hogs farms/IATP + S. Wing, UNC (adapted from Wing et al. 2001)


Leave a Reply

Your email address will not be published. Required fields are marked *