Environmental impacts of animal husbandry in the United States

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Environmental Impacts of animal husbandry in the United States encompasses both the impacts on environment, and broader impacts on consumers and communities. Intensive farming methods exacerbate these impacts. Existing regulations and power structures promoting certain methods of farming and pollution impact policy and environmental justice issues. In practice, these structures include industrial concentrated animal feeding operations, factory farms, animal feeding operations, feedlots, and grazeland.[1]

Environmental justice issues

Often, the adverse effects of CAFOs and other animal agriculture operations are more concentrated around rural communities with largely agricultural economies. For example, consider nitrate pollution from poultry CAFOs. One case study of a CAFO in the American Midwest found that nitrates from a waste lagoon seeped into local groundwater, resulting in nitrate levels 9.6% above what is considered to be safe.[2] Researchers of the study ironically reflected that this case was an “average” example of CAFO pollution.[2] Residents in the local community were discouraged from drinking the water since it had been contaminated, posing a threat to their health.[2]

Primarily, localized CAFO pollution affects low-income communities and communities of color, making this an issue of environmental racism. One study published in 2002 found that the likelihood of residential proximity to CAFOs averaged rates 2.4-3.6 times higher for poorer communities and communities of color than around white, upper-class communities.[3] This disparity could be even larger depending on the state. For instance, in North Carolina, pig CAFOs are roughly 20 times more concentrated around the state’s poorest and most ethnically diverse communities than around the state’s most wealthy and ethnically homogenous communities.[4]

Additionally, low-income people and people of color will continue to suffer from the impacts of modern agriculture policy as:

  • Intensive farming practices accelerates climate change, leading to the loss of arable land and resources, leading to higher produce and animal product costs.[5]
  • Working class jobs are lost as the seafood industry struggles to cope with ocean acidification brought on by similar drivers of climate change.[6]
  • Redlining and other discriminatory zoning practices regulate more waste to areas where people of color and low-income communities are allowed to live, triggering disease and short DALYs.[7]
  • People of color are forced to migrate in hostile political climates due to submerged islands and coastlines.[8]
  • Resource wars, such as the Bolivian Water Wars, break out due to resource scarcity triggered in part by CAFO effects on pollution and climate change.[9][10]

Hog farms

Pot-bellied pigs in Lisbon Zoo 2008.jpg

North Carolina’s number of hog farms grew massively between the mid-1980’s and mid-1990’s, going from the fifteenth to the second largest hog producing state nationwide.[11] These thousands of large-scale hog farms, or CAFOs, are often accompanied by strong offensive odors and fumes containing hydrogen sulfide and ammonia from waste. Nearby residents, mostly consisting of persons of color, report they sometimes have to wear masks to cover their noses and mouths when going outside because the odor is so offensive. Additionally, it is common practice for CAFOs to utilize hog waste as fertilizer for Bermuda grass feed. When fields are sprayed, residents report that the waste spray sometimes hits their homes.[12]

Disparities in distribution of hog farms by race and income are evident based upon census information. For instance: North Carolina’s most densely CAFO populated county as of 2012 is Duplin, found in the southeastern part of the state. According to the US Census Bureau, 25% of Duplin County lives in poverty, 23% are without health insurance, and 26% are Black/African American. Neighboring Sampson county, with the second highest population of hog farms is similar; 21% live in poverty, 20% without health insurance, and 26% are Black/African American. Wake County, the nearest-by Duplin and Sampson without any hog farms, is 11% in poverty, 12% without health care, and 21% Black/African American.[13][14]

Hormone runoff

Further concern over the use of hormones in animal agriculture centers around the hormones getting into the environment. Hormones in excrement and blood infect bodies of water. Specifically, estrogen has been responsible for causing gender recombinance in frog populations.[15]

Climate change

The animal agriculture sector, and specifically CAFOs, has become one of the biggest water pollution sources and contributors to greenhouse gas emissions.[16] Environmentalists, scientists, and farmers fear that protection and expansion of animal feeding operations will endanger the future of agriculture by increasing climate change factors.[17] Effectively, pending climate shifts will result in exacerbated water scarcity, desertification, and a loss of arable farmland.[18] Currently, fertilizers, high power farm machinery, ruminant flatulence, and animal respiration all contribute to greenhouse gas emissions. CAFOs are responsible for 18% of carbon dioxide emissions, 37% of global methane emissions, and 65% of nitrous oxide emissions —forming a grand total of 18% of all greenhouse gas emissions.[19] Climate change is largely driven by positive feedback loops which constantly “significantly accelerate” the rate of change.[20] Once gases such as methane and carbon dioxide are released from storage, they trap heat, contributing to the melting of the arctic. Since there is then less ice to store carbon and reflect heat than there formerly was, the process is accelerated.[21]

Animal product production is the primary contributor to emissions of methane, one of the most potent greenhouse gases responsible for climate change and air pollution. In 2014, methane concentrations rose 12.5 parts per billion, and in 2015, 9.9 parts per billion, surpassing the annual rise of about 0.5 parts per billion a decade ago.[22]


Sonny Purdue (left) talks with FEMA Federal Coordinating Officer (FCO) Mike Bolch (right) at the Georgia EOC.

Donald J. Trump's agricultural platform is an area of contention among scientists, environmentalists, farm communities, and agricultural workers.[23]

On August 16, 2017, Trump appointed Brian Klippenstein as the transition leader for the United States Department of Agriculture.[24] Klippenstein has drawn criticism from sustainability and animal rights advocates due to his status as an executive director for Protect the Harvest, a group demanding unrestricted utilization of non-human animals, despite ethical and environmental consequences.[17]

On January 19, 2017, Trump chose Sonny Perdue to be his Secretary of Agriculture.[25]

Notably, Senator Cory Booker has opposed Trump's agircultural campaign on the basis of animal welfare, supporting "check-off reform."[26]

Climate change

Furthermore, farmers, scientists, and environmentalists fear Trump’s promotion of Big Oil will prove disastrous for global agriculture.[27] Anthropogenic climate shifts since the Industrial Revolution have already resulted in the desertification of 40-41% of arable lands, rendering them unusable for agricultural purposes.[28][29]

Recently, the Trump Administration has "sent unmistakable signals that any agency that conducts climate change research can expect cuts to those programs, with estimates being as high as 60%," despite the fact that this type of research would benefit the industries and voters who backed Trump.[30]

Environmental degradation

Likewise, agricultural and environmental groups expect that Trump's committee's preferences for resource-intensive, large-scale factory-farming methods will degrade natural resources and environmental safety.[31] A few impacts are briefly illustrated below.


Trump’s reversal of the “Clean Water Rule: Definition of “Waters of the United States,” and the Stream Protection Rule are criticized for lifting water pollution regulations.[32] Some agricultural and environmental groups condemn the reversal as it creates potential for contamination of workers and produce. Most animal agriculture establishments are registered as concentrated animal feeding operations (CAFOs) and thus are exempt from treating the waste they produce. Bound by no legal obligation to process or purify blood, urine, feces, or decomposing bodies, CAFOs often store waste in ponds or lagoons. CAFO operators are supposed to take measures to prevent waste from getting into waterways. However, officials often neglect to monitor the employment of preventative tactics or to penalize operators for runoff. Rain, hurricanes, and snowmelt often cause poorly enforced lagoon walls to breach or flood, facilitating the transportation of waste to lakes, streams, and rivers. For instance, in 2016, Hurricane Mathew hit North Carolina.[33] The heavy torrents of water flooded many of the animal waste storage facilities, causing at least 15 waste lagoons to breach.[33] Meanwhile, state and federal authorities neglected to penalize the CAFO operators responsible for ensuring no runoff would reach waterways.[33] Epidemiologists critique the events in North Carolina, as waste transports pathogens to humans, creating a public health threat. Viruses, bacteria, and microorganisms carrying diseases such as swine influenza breed and grow in the waste.[34] These pathogens are then free to travel via air or be transported via contact with products that are headed to stores, ending up in environments where they can make human communities sick.[35] Additionally, with climate change come increased extreme weather incidences. For example, major storms in North Carolina this past year have resulted in leakage of huge levels of liquid waste from CAFOs into major streams and rivers.[16]


Existing animal agriculture policy is also controversial due to its effects on air pollution. The Socially Responsible Agricultural Project calculates that “liquefied animal waste” from animal agriculture produces 160 noxious gasses.[35] It is important that emissions of these gasses be regulated because they threaten the health of organisms, including humans.[35] For instance, the Excel Dairy Company of Minnesota formerly would discharge such voluminous quantities of hydrogen sulfide — a gas known for its rotten egg odor and its toxic effects to the nervous system damage into the surrounding community.[35] In 2009, this pollution increased to such a degree that officials feared that the local community would suffer from significant respiratory and nervous system damage if the company immediately did not take steps to halt gas emissions. The company ignored all official warnings.[35] As a result, the Minnesota Pollution Control Agency was forced to shut down the operation, while urgently recommending that neighboring residents immediately evacuate the area.[35]

Furthermore, animal agriculture constitutes a threat to public health and safety by emitting high levels of particulate matter. Concentrated animal feeding operation staples such as feed, bedding materials, animal dander, feathers, and manure all become airborne with light winds.[36] Local citizens can then breathe in these pollutants, triggering problems such as bronchitis, deteriorated lung function, and organic dust toxic syndrome.[36] For instance, a 2009 study on CAFOs and health complications in the Netherlands found that citizens in regions with high concentrations of CAFOs tended to have a roughly 200% higher rate of infectious disease acquisition due to particulates in the air.[37] These results were especially high in children between the ages of zero and four.[37] Additionally, CAFOs in states like Mississippi and North Carolina are also focal points of environmental racism, as CAFOs tend to be five times more populated by people of color than by white residents. Air pollution associated with CAFOs, and therefore these minority groups, is shown to lead to higher levels of stress, teen pregnancies, and mental health problems.[38]

Antibiotic resistance

Antibiotic resistance art.jpg

More controversy is sparked by the animal animal agriculture industry's role in the accelerating the evolution of superbugs. CAFO operators almost always include antibiotics in the daily feed of animals.[39] This practice is usually undertaken because CAFOs are operated in crowded conditions where animals are constantly exposed to waste, subjugated to open wounds and abrasions, and receive no veterinary care, and animals are indiscrimintately forced onto antibiotics whether or not they need them.[39] Hence, it is necessary for operators to ensure animals receive extra support to their immune systems in the most efficient and cost-effective way.[39] In addition, animal muscle producers use antibiotics to increase the weight of animals, fattening them for market.[40] The frequent use of antibiotics encourages pathogens to quickly evolve new, stronger strains to resist the antibiotics.[41] Unsanitary factory conditions allow for rapid contact between waste and butchered products waiting to be shipped to stores, allowing the resistant pathogens to be shipped to the public and circulate to new areas where resistance can increase.[42] This can cause disease outbreaks.[43] Many superbug strains have already developed, including escherichia coli, salmonella, campylobacter, enterococcus, and staphylococcus.[44] For instance, one superbug bacterium responsible for causing staph infections kills more Americans each year than does auto-immune deficiency syndrome (AIDS).[45] 23,000 people die every year of infections caused by antibiotic-resistant bacteria in the United States.[43] As greater numbers of bacteria develop antibiotic immunity, doctors find it increasingly difficult to offer cures for future diseases.[46]


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