Environmental impact of pig farming

Effects on air quality

Communities located near factory pig farms experience negative health and environmental effects due to several factors associated with industrial pig farming. One main issue that arises out of intensive animal agriculture is the waste that the huge number of animals produce. Pig waste is similar to human waste; filled with bacteria and high amounts of ammonia. At most intensive pig farms, hog waste is kept in large open-air pits called lagoons where waste is broken down by anaerobic bacteria and then sprayed onto crops as fertilizer. This is called the lagoon and sprayfield system and remains legal in the United States, including in states like North Carolina where there have been on-going efforts in the NC legislature to ban open-air lagoon and sprayfield system practices in the state and replace these with more environmentally sound waste management practices.

The waste then reaches neighboring towns, resulting in civilians not being able to even leave their house in order to avoid pig waste filled air. People living in nearby towns have suffered a variety of adverse health effects including respiratory diseases, infections, increased risk of cancer, and other health risks.

The nitrogen from pig waste can also contribute to acid rain in the local areas; team of scientists from the US Agricultural Research Service and the US Department of the Environment has examined and noted that within wastewater lagoons in North and South Carolina, there are a host of genes involved in the process of turning ammonia into nitrogen.

One case study, conducted by Environmental Health Perspectives, sought to prove that malodor and pollutant concentrations from swine operations are associated with stress, altered mood, and increased blood pressure. For two weeks, adult volunteers living near swine operations in North Carolina sat outside for ten minutes twice a day. They reported levels of hog odor, and recorded their blood pressure. The study found that like noise and other similar environmental stressors, the malodors from the swine operations were likely associated with an increase in blood pressure, which could contribute to an increase in chronic hypertension.

Disease spread

There are many documented incidences of disease outbreaks occurring due to the presence of pig farms in a given community, particularly industrial pig farms. MRSA (Methicillin-resistant Staphylococcus aureus, a type of anti-biotic resistant bacteria) outbreaks have been correlated to an individual working in a pig farm, likely attributed to the strong antibiotics often used in industrialized pig farms.

In a population based study completed by a group of scientists where the results were published in an article, they compared the health of the farmers that work on a conventional farm versus Antibiotic free farms. In this study they would test around 0 to 28 workers per farm for the MRSAinfection. The scientists found that 31 out of 148 tested positive for the infection and 27 of this farmers worked on farms where MRSA was found amongst the swine they worked with. These results can show us that those who work around swine that are given antibiotics have a higher chance of developing the MRSA infection due to their exposure to the pigs on a daily.

Another example of a virus spreading from pigs to humans is the Hepatitis E Virus. This virus is the aetiological agent for the Hepatitis E, HEV has also been shown to be the second most cause of acute clinical hepatitis among adults. Currently, there has been an increase in the number of cases recorded in Italy transmitted from pigs. There was a study completed by a group of scientists published. In this study the researchers found that 97% of the farms resulted in enzyme-linked immunosorbent assay test for HEV antibodies. They also found that %50 of the swine tested positive for the HEV antibodies. This concludes that there is a correlation between working with pigs and the HEV infection.

Other diseases can also spread in pig farms such as Salmonella, Toxoplasma, and Campylobacter. Many of these diseases are preventable given proper safety precautions such as washing hands and clothes, wearing face masks, and covering any open wounds when coming into contact with pigs. Improvements in farmer education about diseases are often cited as the reason for the lack of increase in disease outbreaks in North Carolina despite an increase in pig population by a factor of four in the years leading up to 1998.

Around the world

Australia

Australia is home to one of the largest pork industries in the world with farms across Australia collectively containing over 300,000 pigs but there are high levels of water pollution. While clean drinking water is essential to the growth and development of pigs, high levels of hard minerals and water-borne pathogens have been found in many of Australia's pig farms. Poor water management poses a threat to the well-being and performance of pig production.

China

Pork is the most popular meat in China. Intensive pig farming leads to smog and water pollution in some Chinese regions. According to the Chinese Ministry of Agriculture, livestock farming is the leading cause of water pollution in the country.

In Hong Kong, a study was done on farmers to identify key barriers and challenges associated with pig farming in that area. The farmers revealed that the biggest obstacle for improvement of pig husbandry practices was impeded by outdated government regulations.

France

Swine farm manure leads to toxic algal blooms in the French region of Brittany. Industrial pig farming has become a common practice for producing pork in the country of France. However, the local community of consumers has become skeptical of intensive industrial pig production. Safety factors, quality of meat and impacts on the environment are all reasons for the decrease of pig farming production throughout France. Organic methods for raising swine has enticed 23% of producers and majority of the consumers support this.

Netherlands

The Netherlands has one of the densest livestock sectors in the world. In 2019, a Dutch court halted the expansion of pig and other farms to prevent nitrogen pollution, which had led to algal blooms, smog, and soil acidification.

United States

The United States Environmental Protection Agency (EPA) calls intensive farms above a certain threshold concentrated animal feeding operations (CAFOs).

In the 1970s, a series of laws, known as "Murphy's Laws", were passed in North Carolina to eliminate the sales tax on hog farm equipment and to prevent authorities from using authority to prevent and address odor issues. After the passage of Murphy's Laws and other similar bills, there was a rapid increase in industry in North Carolina, where the population of swine was estimated around 9-10 million. Each of those hogs produces eight times the feces as a human, causing a crucial need for regulation and maintenance for that waste.

Regulation and laws could not keep up with the rapid explosion of the hog farming and spread of CAFOs in the early 2000s, which has caused severe harm and health impacts over time. Furthermore, agencies with jurisdiction over CAFOs are typically environmental or natural resource state-run agencies, as opposed to local health departments. This is an advantage for addressing environmental impacts but a disadvantage for human health concerns, as the majority of local health issues get overlooked by state-run agencies. Additionally, although there are laws and regulations in place, such as the Swine Farm Environmental Performance Standards Act, which prohibits new waste lagoons and mandates that new CAFOs must use technology that will prevent discharge of waste, these regulations do not mandate for existing CAFOs to clean up or regulate the pollutants within their lagoons. These regulations also make it more costly to clean up these wastes and prevent other consequential harms, without actually assisting farms in shouldering these costs, making it difficult for them to actually act on these regulations.

Ag-gag laws have made it even more difficult for farms to be held accountable for their actions, and for communities to have a transparent view of farm operations. These laws forbid the undercover video-taping or documenting of farms without the consent of the farm's owner. These laws are targeted at keeping animal rights and environmental activists away from the most damaging farm operations. These laws emerged in the 90's and are now in effect in North Carolina, Utah, Missouri, Idaho, and Iowa, and is being considered in at least five states. These bills have the potential to exacerbate animal abuse on these large scale farms and CAFOs, as well as threaten community health, social justice, and consumer health by restricting organizations and individuals from sharing pertinent information about the food supply.

The EPA does require that operations with qualified number of pigs must demonstrate that there is no runoff from their farm, in order for them to acquire a permit. But, this regulation varies from state to state and most of the time, enforcement only happens in response to citizen complaints, rather than active monitoring. Further, locally developed policies often have inefficient resources and abilities to enforce regulation, and often don't address transboundary issues that arise with pig operations that exist across multiple states. And with Federal laws such as the Clean Water and Clean Air act, regulation is delegated to state agencies, but these agencies don't usually take on active regulation until the damage has been done. Further, many operations are exempt because they have been grandfathered in, meaning they have been in operation for so long that they are not subject to the new laws.

North Carolina

In 2014, National Geographic wrote a piece on the extent of the contamination in North Carolina. Swine sales in the state (second largest pork producer in the nation) were nearly $3 billion in 2012, and the state received attention in 1999 when Hurricane Floyd caused waste pods on the swine ponds to overflow, polluting the water supply. National Geographic suggested that despite the execution of a $17 million research project on waste in the area, no one in the state seemed to know what to do with the pig waste, which was a huge issue considering that there are nearly as many pigs as people. Nearly two decades later when Hurricane Florence hit the coast of North Carolina in 2018, hog waste remained a major concern. According to the NC Pork Council, 98% of hog lagoons experienced minimal impact. The NC Department of Environmental Quality identified six hog farms with anaerobic lagoons that suffered structural damage and 28 farms that had lagoons overflow due to the floodwater.

Social justice concerns regarding agricultural lands in rural areas have been rising because of the way minority communities are disproportionally affected by hazards and health risks associated with pig farming. Due to the immense amount of waste produced by pigs, often foul odors and airborne molecules disturb local citizens. There is an unfair distribution of these swine farms, where around 90% are located along the "black-belt", which is known for its previous production of cotton and tobacco farming. Many of the minority farmers are being put out of business because of concentrated animal feeding operations (factory farms). Staggering statistics show that compared to white-owned farms, black-owned farms have declined by 98% and there are only about 18,000 today. Furthermore, environmental justice activists have described the apparent linkage between air pollution and toxic hazards with the demographic of suburban communities that show black and low-income communities being the main targets.

Improvements to pig farming practices

Due to the many environmental repercussions associated with common pig farming techniques, new technologies were created and tested to help prevent these problems. Manure from swine contains excess nitrogen and phosphorus which gets released into nearby water bodies, polluting streams and rivers and contributing to eutrophication. In order to combat this issue, scientists in North Carolina have tested treatment technologies that are designed to separate the manure. Once the pigs drop their manure, a screening device can be used to separate the solid particles from the liquids. A filtration process can be even more effective with removing extra nitrogen and phosphorus that is still remaining. A filter cloth can catch any remaining particles with a pore size less than an inch. Applying this method can greatly reduce organic matters that come from manure which end up in near-by waterways causing pollution and eutrophication.

Another more unconventional way to solve the solution the effects of large Industrial farming is possibly promoting more smaller or medium sized farms. Now I know this may be a challenging thing to do since the Industrial Pig farming has grown to be such a huge industry. Though promoting smaller farms can result in many benefit such as less waste being inputed into the environment and higher quality meat production. In an article a group of scientist found that the smaller farms allowed for less impact to occur on the environment than the large Industrial farms. The study also shows how the smaller farms can result in not only environmental benefits but also economic benefits. This study shows how small pig farming is not only beneficial for the environment but for us as well.

In popular culture

In The Simpsons Movie, Homer Simpson dumps a silo of pig manure into a lake near the town of Springfield, provoking an environmental catastrophe that leads the US Environmental Protection Agency (EPA) to quarantine Springfield with a giant glass dome.