Health Social Issues

Unhealthy Conditions for Farm Animals are — No Surprise — Bad for Humans, Too

12 min read

New viral pandemics are just one of the many public health crises linked to factory farming. In this article, discover how factory farms contribute to antibiotic resistance, pollution, animal cruelty, foodborne pathogens, and other illnesses — making them a danger to both animals and humans alike.

By Tia Schwab, Stone Pier Press

Editor’s Note: The following article is an opinion-editorial (commonly referred to as an “op-ed”). While most of the articles posted on the Food Revolution Network site are ones our staff have written, the op-eds we publish are different. Since we didn’t write them, we can’t always vouch for, and may even not agree with, everything they say. However, we present them to you because we believe they make an important contribution to the conversation that promotes our mission of healthy, ethical, and sustainable food for all.

Last spring, a man was admitted to Mt. Sinai Hospital in Brooklyn for surgery. A blood test revealed he was positive for the deadly antibiotic-resistant fungus, C. auris, and he was quickly quarantined. After three months of intensive treatment, he died. In order to eradicate traces of the germ from his room, the hospital had to acquire special cleaning equipment, rip out parts of the ceiling and floor, and get rid of some treatment tools. “Everything in the room was positive,” Dr. Scott Lorin, the hospital’s president, told The New York Times. The germ, deemed an “urgent threat” by the Centers for Disease Control and Prevention (CDC), has so far been found in two more states, New Jersey and Illinois.

Experts warn it’s only going to get worse. In 2014, the Review on Antimicrobial Resistance, commissioned by the UK Government and Wellcome Trust, estimated that 700,000 people around the world die each year due to drug-resistant infections. Without action, that number could grow to 10 million per year by 2050. A leading cause of antibiotic resistance? The misuse and overuse of antibiotics on factory farms.

Animal Welfare Issues on Factory Farms

Flourishing antibiotic resistance is just one of the many public health crises produced by factory farming. Other problems include foodborne illness, flu epidemics, the fallout from poor air and water quality, and chronic disease. All of it can be traced to the current industrial approach to raising animals, which values “high stocking density” over safe working conditions and farm animal welfare.

Oversight for the way factory farms operate and manage waste is minimal at best. No federal agency collects consistent and reliable information on the number, size, and location of large-scale agricultural operations, nor the pollution they’re emitting. There are also no federal laws governing the conditions in which farm animals are raised. And most state anti-cruelty laws do not apply to farm animals.

For example, Texas, Iowa, and Nebraska have excluded livestock from their animal cruelty statute and instead created specific legislation aimed at farm animal abuse that makes accepted or customary husbandry practices the animal welfare standard. After New Jersey created similar legislation, the New Jersey Society for the Prevention of Cruelty to Animals (NJSPCA) sued the New Jersey Department of Agriculture (NJDA), claiming that “routine husbandry practices” was too vague. NJSPCA won, and as a result, the NJDA has created more specific regulations.

Farm Animal Cruelty Practices

(Editor’s Note: Trigger Warning – The following details may be upsetting to read about. We in no way seek to validate or imply condoning of the horrendous animal cruelty described.) Tail docking of cattle is only allowed when performed “by a veterinarian for individual animals.” And debeaking of birds is only allowed if performed by a knowledgeable individual and in compliance with the United Egg Producers Animal Husbandry Guidelines for US Egg Laying Flocks.

In North Carolina, any person or organization can file a lawsuit if they suspect animal cruelty, even if that person does not have “possessory or ownership rights in an animal.” In this way, the state has “a civil remedy” for farm animal cruelty.

The general lack of governmental oversight results in cramped and filthy conditions, stressed-out animals and workers, and an ideal setup for the rampant spread of disease among animals, between animals and workers, and into the surrounding environment through animal waste.

Antibiotic Resistance

vet administering vaccine to pigs

The Problem

In 2017, nearly 11 million kilograms of antibiotics — including 5.6 million kilograms of medically important antibiotics — were sold in the US for food animals. Factory farms use antibiotics to make livestock grow faster and control the spread of disease in cramped and unhealthy living conditions. While antibiotics do kill some bacteria in animals, resistant bacteria can, and often do, survive and multiply, contaminating meat and animal products during slaughter and processing.

What It Means for You

People can be exposed to antibiotic-resistant bacteria by handling or eating contaminated animal products, coming into contact with contaminated water, or touching or caring for farm animals, which of course makes a farmworker’s job especially dangerous. Even if you don’t eat much meat or dairy, you’re vulnerable. Resistant pathogens can enter water streams through animal manure and contaminate irrigated produce.


The European Union has been much more aggressive than the US in regulating antibiotic use on factory farms, banning the use of all antibiotics for growth promotion in 2006. But the US is making some progress, too. Under the FDA’s new rules, which went into effect in January 2017, antibiotics that are important for human medicine can no longer be used for growth promotion or feed efficiency in cows, pigs, chickens, turkeys, and other food animals.

In addition, 95% of medically important antibiotics used in animal water and feed for therapeutic purposes were reclassified, so they could not be bought over the counter. And a veterinarian would have to sign off on its use in animals. As a result, domestic sales and distribution of medically important antimicrobials approved for use in food-producing animals decreased by 43% from 2015 (the year of peak sales) through 2017, reports the FDA.

However, the FDA still allows routine antibiotic use in factory farms for disease prevention in crowded and stressed animals, so these new rules aren’t nearly enough, says Matthew Wellington, antibiotics program director for the US Public Interest Research Group Education Fund. “The FDA should implement ambitious reduction targets for antibiotic use in the meat industry, and ensure that these medicines are used to treat sick animals or control a verified disease outbreak, not for routine disease prevention,” Wellington said in a statement to the Center for Infectious Disease Research and Policy.

National Resources Defense Council senior attorney Avinash Kar agrees. “We are seeing real progress, but the American meat industry continues to have a drug problem. And the clock is ticking to solve it,” she says. “Far more antibiotics important to humans still go to cows and pigs — usually when they’re not sick — than to people, putting the health of every single one of us in jeopardy.”

Water and Air Pollution

dirty sewage water pouring into drainage ditch

The Problem

Livestock in this country produces between 3 and 20 times more waste than people in the US produce, according to a 2005 EPA report, or as much as 1.2–1.37 billion tons of manure a year. Some estimates are even higher. Manure can contain “pathogens such as E. coli, growth hormones, antibiotics, chemicals used as additives to the manure or to clean equipment, animal blood, silage leachate from corn feed, or copper sulfate used in footbaths for cows,” reports a 2010 report by the National Association of Local Boards of Health. Though sewage treatment plants are required for human waste, no such treatment facility exists for livestock waste.

Since this amount far exceeds what can be used as fertilizer, animal waste from factory farms typically enters massive, open-air waste lagoons, which spread airborne pathogens to people who live nearby. If animal waste is applied as fertilizer and exceeds the soil’s capacity for absorption, or if there is a leak or break in the manure storage or containment unit, the animal waste runs off into oceans, lakes, rivers, streams, and groundwater.

Extreme weather increases the possibility of such breaks. Hurricane Florence, for example, flooded at least 50 hog lagoons when it struck the Carolinas last year, and satellite photos captured the damage. Eight years ago, the EPA reported that 29 states identify animal feeding operations as contributing to water pollution. To offer some idea of what that looks like, the EPA reported in 1998 that factory farm runoff polluted 35,000 miles of river in 22 states.

Whether or not the manure is contained or spread as fertilizer, it can release 400 different types of harmful gases, including ammonia and hydrogen sulfide, as well as particulate matter comprised of fecal matter, feed materials, pollen, bacteria, fungi, skin cells, and silicates into the air. Manure is also an abundant source of nitrate, which seeps into groundwater and can be toxic at elevated levels.

What It Means for You

Pathogens can cause diarrhea and severe illness or even death for those with weakened immune systems. And gases like ammonia and hydrogen sulfide can cause dizziness, eye irritation, respiratory illness, nausea, sore throats, seizures, comas, and death. Particulate matter in the air can lead to chronic bronchitis, chronic respiratory symptoms, declines in lung function, and organic dust toxic syndrome.

The CDC has reported that children raised in communities near factory farms are more likely to develop asthma or bronchitis, and that people who live near factory farms may experience mental health deterioration and increased sensitization to smells. And nitrates in drinking water have been connected to birth defects, miscarriages, and poor general health. For infants, it can mean blue baby syndrome and even death.


It is difficult to hold factory farms accountable for polluting surrounding air and water, largely for political reasons. Before the 2020 election, the GOP-controlled Congress and the Trump administration excused big livestock farms from reporting air emissions, for instance, following a decade-long push for special treatment by the livestock industry. The exemption indicates “further denial of the impact that these [emissions] are having, whether it’s on climate or whether it’s on public health,” says Carrie Apfel, an attorney for Earthjustice. In a 2017 report from the EPA’s Office of the Inspector General, the agency admitted it has not found a good way to track emissions from animal farms and know whether the farms are complying with the Clean Air Act. 

No federal agency even has reliable information on the number and locations of factory farms, which, of course, makes accountability even harder to establish. Two Stanford scholars are hoping to change that, however. Professor Daniel Ho and doctoral candidate Cassandra Handan-Nader published a paper in Nature Sustainability in 2019 demonstrating how a new map-reading algorithm could help regulators identify CAFOs more efficiently. They retrained an existing image-recognition model to recognize large-scale animal facilities from publicly available satellite images. The researchers estimate that their algorithm can capture 95% of existing large-scale facilities using less than 10% of the resources required for a manual census.

Foodborne Illness

danger sign for salmonella outbreak

The Problem

The United States has “shockingly high” levels of foodborne illness, according to the Bureau of Investigative Journalism and The Guardian. And unsanitary conditions at factory farms are a leading contributor.

In a study of 47 meat plants across the US, investigators found that hygiene incidents occur at rates experts described as “deeply worrying.” One dataset covered 13 large red meat and poultry plants between 2015 and 2017 and found an average of more than 150 violations a week, or 15,000 violations over the entire period. Violations included unsanitary factory conditions and meat contaminated with blood, septicemic disease, and feces.

“The rates at which outbreaks of infectious food poisoning occur in the US are significantly higher than in the UK, or the EU,” said Erik Milstone, a food safety expert at Sussex University interviewed by The Guardian. “Poor hygiene in the meat supply chain is a leading cause of food poisoning in the US.” 

Poor sanitary practices allow bacteria like E. coli and Salmonella, which live in the intestinal tracts of infected livestock, to contaminate meat or animal products during slaughter or processing. Contamination occurs at higher rates on factory farms because crowded and unclean living conditions increase the likelihood of transmission between animals. It also stresses out animals, which suppresses their immune response making them more susceptible to disease. The grain-based diets used to fatten cattle can also quickly increase the risk of E. coli infection. In poultry, the practice of processing dead hens into “spent hen meal” to be fed to live hens has increased the spread of Salmonella.

What It Means for You

According to the CDC, roughly 48 million people in the US suffer from foodborne illnesses annually, with 128,000 hospitalizations and 3,000 deaths each year. Salmonella accounts for approximately 11% of infections, and kills more people every year than any other foodborne illness.


In January of 2011, President Obama signed The Food Safety Modernization Act (FSMA), the first major piece of federal legislation addressing food safety since 1938. FSMA grants the FDA new authority to regulate the way food is grown, harvested, and processed, and new powers such as mandatory recall authority. The FSMA “basically codified this principle that everybody responsible for producing food should be doing what the best science says is appropriate to prevent hazards and reduce the risk of illness,” according to Mike Taylor, co-chairman of Stop Foodborne Illness and a former deputy commissioner for foods and veterinary medicine at the FDA. “So we’re moving in the right direction.”

However, almost ten years later, the FSMA is still being phased in due to a shortage of trained food-inspectors and a lack of funding. “Congress has gotten about halfway to what it said was needed to successfully implement” the act, Taylor said.

The Flu

woman blowing nose and checking body temperature

The Problem

Both the number and density of animals on factory farms increase the risk of new virulent pathogens, according to the US Council for Agriculture, Science, and Technology. In addition, transporting animals over long distances to processing facilities brings different influenza strains into contact with each other, so they combine and spread quickly. Pigs are susceptible to both avian and human flu viruses, so they can serve as ground zero for all sorts of new strains. Because of intensive pig farming practices, “the North American swine flu virus has jumped onto an evolutionary fast track, churning out variants every year,” according to a report published in Science magazine.

What It Means for You

These viruses can become pandemics. In fact, viral geneticists link the genetic lineage of H1N1 to a strain that emerged in 1998 in US factory pig farms. The CDC has estimated that between 151,700 and 575,400 people worldwide died from the 2009 H1N1 virus infection during the first year the virus circulated.

Breast, Prostate, and Colon Cancer

hands holding blue ribbon for cancer awareness Dangsungnoen

The Problem

Factory farms in the US use hormones to stimulate growth in two-thirds of beef cattle. On dairy farms, 54% of cows are injected with recombinant bovine growth hormone (rBGH), a growth hormone that increases milk production.

What It Means for You

The health effects of consuming animal products treated with these growth hormones is an ongoing international debate. Some studies have linked growth hormone residues in meat to reproductive issues and breast, prostate, and colon cancer, and IGF-1 has been linked to colon and breast cancer. However, the FDA, the National Institute of Health, and the World Health Organization have independently found that dairy products and meat from rBGH-treated cows are safe for human consumption. Because risk assessments vary, the EU, Australia, New Zealand, Japan, Israel, and Argentina have banned the use of rBGH as a precautionary measure. The EU has also banned the use of six hormones in cattle and imported beef.


USDA guidelines allow beef products to be labeled with “no hormones administered” and dairy products to be labeled “from cows not treated with rBST/rBGH” if the producer provides sufficient documentation that this is true. Consumers can use this information to make their own decisions about the risks associated with hormone-treated animal products.

What You Can Do

hands holding veggie burger

You can vote for local initiatives that establish health and welfare regulations for factory farms. But only a tiny number of states, including California and Massachusetts, are even putting relevant propositions on the ballot. Another option is to support any of the nonprofits that are, in lieu of effective government action, taking these factory farms to task. The Environmental Working Group, Earthjustice, and Animal Legal Defense Fund are among those working hard to check the worst practices of these CAFOs. Another good organization is the Socially Responsible Agriculture Project (SRAP), which works with local residents to fight the development of factory farms in their own backyards.

Buying humanely-raised animal products from farms and farmers you trust is another way to push back against factory farming. Sadly, products from these smaller farms make up only a fraction of the total. In the US, roughly 99% of chicken, turkeys, eggs, and pork, and 70% of cows, are raised on factory farms.

You can support “clean” burgers, chicken, and pork, by buying it once it becomes widely available. Made from animal cells, the process completely spares the animal and eliminates the factory farm. “The resulting product is 100% real meat, but without the antibiotics, E. coli, Salmonella, or waste contamination,” writes the Good Food Institute, a resource for many clean meat start-ups, which currently number 27. Says Paul Shapiro, CEO of The Better Meat Co., “this promising field will only continue to get bigger.”

Demanding Change

In the meantime, you can register your objection to factory farming by doing your bit to reduce demand for their products. In short, eat less meat and dairy, and more plant-based proteins. Fortunately, the days when that meant forking in soy dogs and potato burgers are long gone. More than $13B were invested in plant-based meat, egg, and dairy companies in 2017 and 2018 alone, according to the Good Food Institute. And Beyond Meat’s IPO debut marked the most successful one since the year 2000.

Lest you think that what you do on your own can’t possibly make a difference, consider one of the major drivers behind all this new investment: consumers are demanding change. Says Bruce Friedrich, executive director of Good Food Institute: “Shifting consumer values have created a favorable market for alternatives to animal-based foods, and we have already seen fast-paced growth in this space across retail and foodservice markets.”

Tia Schwab wrote this story as a News Fellow at Stone Pier Press, an environmental publishing company with a focus on food. Tia is currently working for a nonprofit in Washington, DC while completing her Master’s of Food and Agriculture Law and Policy at Vermont Law School. She received her BA in Food Systems and Public Health from Stanford University.

Tell us in the comments:

  • Do you eat meat from factory farms?
  • Were you aware of the extent of unhealthy conditions prevalent on factory farms?
  • What other ways can you think of to combat farm animal cruelty and protest factory farm conditions?

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