In the United States, the vast majority of farm animals are raised in concentrated animal feeding operations (CAFOs), which are also commonly known as factory farms. These massive, industrial facilities raise tens or even hundreds of thousands of livestock animals — such as cows, pigs, and chickens — in tightly confined spaces, creating a range of ethical, environmental, and public health concerns. What are CAFOs? They are an example of industrial agriculture. 

Industrial agriculture definition  

Industrial agriculture, also known as intensive agriculture, aims to produce as many calories as possible as cheaply as possible – often without regard for the well-being of animals, impacted communities or the environment. 

What are CAFOs?  

The Environmental Protection Agency (EPA) defines an animal feeding operation (AFO) as an agricultural operation where animals are kept in confined spaces and fed or maintained for extended periods, usually over 45 days within a year. An AFO may be considered a concentrated animal feeding operation (CAFO) based on the number and type of animals that it confines. For example, EPA defines large CAFOs as: 

• Cattle: A beef operation, or factory farming of cows, is considered a large CAFO if it houses 1,000 or more cattle, whereas the threshold for dairy cows is 700 or more.  

• Hogs: The threshold for being considered a large CAFO is having 2,500 or more hogs.  

• Chickens: A large CAFO for egg-laying hens or broiler chickens has 30,000 or more birds. 

However, it is not always size dependent, as an AFO may also be considered a CAFO under federal law if it is a “significant contributor of pollutants.” 

These facilities are designed to maximize food production by raising large numbers of livestock animals in cramped, inhumane conditions. Government subsidies and a lack of regulation have led to factory farming becoming the dominant form of meat and dairy production in the U.S. Industry- friendly government policy has also contributed to extreme consolidation within the sector, with just a handful of corporations controlling nearly every aspect of supply chains, from production to processing.  

This vast scale of factory farming of chickens, factory farming of cows, and other livestock animals generates excessive amounts of concentrated waste and toxic emissions. Moreover, the sheer number of animals packed into these facilities, often without access to pasture or the ability to exercise natural behaviors, results in immense animal cruelty.  

What are CAFOs’ environmental impacts?  

On top of wondering “what are CAFOs?”, you may also ask “what are their impacts?” The environmental consequences of CAFOs are severe and wide-reaching. Factory farms contribute to air and water pollution, deforestation, and climate change, all of which disproportionately affect low-income communities and communities of color. This is a significant environmental justice issue as CAFOs are often intentionally located in areas where marginalized communities lack the political or economic power to adequately address the negative impacts of these industrial operations.  

One of the most harmful byproducts of CAFOs is the large quantity of manure produced by the confined animals. This waste is often stored in massive pits, known as manure lagoons, before being sprayed on nearby fields, leading to serious environmental problems: 

• Water contamination: The manure often seeps into local water sources, contaminating drinking water with nutrient pollution, harmful pathogens, and antibiotic-resistant bacteria. 

• Air pollution: Manure generates noxious odors and air pollution, leading to respiratory problems, eye irritation, and other health issues for nearby residents. 

• Soil degradation: Excessive amounts of nutrients like nitrogen and phosphorous, alongside other pollutants, in manure can also damage soil quality, leading to reduced agricultural productivity in the long run. 

Furthermore, CAFOs are major contributors to climate change, with animal agriculture accounting for a third of U.S. methane emissions, 20% of global greenhouse gas emissions and nearly 60% of emissions from the global food system. According to the EPA, the agriculture sector is the largest source of methane emissions in the United States, mostly from the digestive process of ruminant animals (e.g., cattle and sheep) and from animal manure that is stored in large open pits or lagoons. Methane is 80 times as potent as carbon dioxide at trapping heat in the atmosphere over a twenty-year period, and concentrations have more than doubled over the last two centuries.  

What are CAFOs’ impacts on people?  

For people living near CAFOs, the massive amounts of manure not only degrade their environment but also create serious public health issues. These communities are frequently exposed to harmful pollutants, including ammonia, methane, and hydrogen sulfide. Studies have shown that people living near factory farms face higher risk and severity of respiratory illnesses, digestive issues, headaches, as well as chronic conditions such as asthma and chronic obstructive pulmonary disease. They also suffer a reduced quality of life, including lower property values and mental stress, due to pollution from CAFOs. 

The cramped, unsanitary conditions of CAFOs are breeding grounds for infections and diseases, which can spread rapidly through the confined animal populations and in turn to people. Diseases like bird flu, salmonella, E. coli, and Hepatitis E are common in industrial livestock facilities and factory farming of chickens, posing significant risks to both animals and humans. Due to the highly confined conditions, the overuse of non-therapeutic antibiotics is common in CAFOs and contributes to the rise of antibiotic-resistant bacteria, which can be transmitted to humans, making it harder to treat infections. Furthermore, cattle and hogs raised in CAFOs are often fed pesticide-drenched soy and grains, along with added growth-promoting hormones and other chemicals that make their way into the meat that people eat. 

The workers employed in CAFOs and slaughterhouses are at an increased risk of injury and illness due to exposure to sick animals as well as the excessive pollution. The industrial livestock sector is associated with the highest rates of worker injury. Working around dangerous equipment on a daily basis means you are more likely to cause an accidental amputation or other major injury. And being around constant cruelty and death often leads workers to experience PTSD and depression.  

Fighting Factory Farms 

The widespread use of CAFOs raises urgent questions about the future of our food system. The current industrial agriculture definition and model, defined by intensive livestock production, heavy use of pesticides, and monoculture crops, is unsustainable and harmful to people, animals, and the planet.  

Improving the way we produce food starts by implementing policies that support a just transition towards a healthy, fair, and regenerative food system: Our government must strengthen oversight of the industrial animal agriculture sector, curb the extensive subsidies and incentives that prop up factory farms, and shift toward organic and plant-forward menus in schools and other public institutions.