CAFO regulations

Evidence Rating  
Evidence rating: Expert Opinion

Strategies with this rating are recommended by credible, impartial experts but have limited research documenting effects; further research, often with stronger designs, is needed to confirm effects.

Disparity Rating  
Disparity rating: Potential to decrease disparities

Strategies with this rating have the potential to decrease or eliminate disparities between subgroups. Rating is suggested by evidence, expert opinion or strategy design.

Health Factors  
Decision Makers
Date last updated

Animal feeding operations (AFOs) keep and raise animals in a confined area for 45 days or more in any 12-month period and do not sustain vegetation in the normal growing season. Confined animal feeding operations (CAFOs) are AFOs that meet certain size thresholds, manure and waste discharge criteria, or are otherwise designated by authorities as significant contributors of pollutants. A large swine CAFO, for example, has over 10,000 hogs, while a designated small CAFO has less than 750. Medium CAFOs are designated based on their size and contact with surface water, using either manmade ditches or pipes to carry manure or wastewater to surface water or having animals confined in areas where surface water passes through1. CAFOs are regulated by the federal Clean Water Act (CWA) under the National Pollution Discharge Elimination System (NPDES) permitting program1. State and local governments can establish additional regulations to further limit CAFO location, size, and pollution discharge, and increase monitoring, enforcement, and assessment of pollution prevention practices. State and local regulations can also require certification and review of comprehensive nutrient management plans (CNMPs) or manure management plans and expand CNMP requirements2, 3. State and local regulations vary4.

What could this strategy improve?

Expected Benefits

Our evidence rating is based on the likelihood of achieving these outcomes:

  • Reduced run-off

  • Improved water quality

Potential Benefits

Our evidence rating is not based on these outcomes, but these benefits may also be possible:

  • Improved air quality

  • Improved health outcomes

  • Improved quality of life

  • Reduced emissions

What does the research say about effectiveness?

State or local confined animal feeding operation (CAFO) regulations are a suggested strategy to reduce environmental contamination and improve water quality4, 5. Available evidence indicates changes in CAFO management practices6, 7 and CAFO siting8 in response to regulations. However, additional evidence is needed to confirm the effects of state and local regulations and management changes on environmental contamination and water quality.

CAFOs have been shown to pollute water with excess nutrient run-off and nitrate contamination9, 10, 11, 12, estrogen and steroids13, 14, and bacteria and fecal contamination11, 15, 16, 17, 18. A 16-state study finds watersheds with significant CAFO clusters are associated with higher total phosphorus (TP) and total nitrogen (TN) levels19. For example, in Iowa, nitrate in streams is much higher where livestock are most concentrated, compared to other watersheds20. A Wisconsin-based study finds that for each CAFO added to a regional watershed, average phosphorus levels increase by 1.7% and average ammonia levels by 2.7%. These results suggest that each CAFO produces over $203,000 in damages to surface water quality every year21. Nitrogen-based fertilizer used in farming contributes to elevated nitrate in communities’ drinking water, which is associated with human health risks, including increased risk of some cancers22 such as gastric cancer, though more research is needed23.

CAFO waste can increase arsenic levels24, hormone concentrations, and algae blooms that can lead to fish kills4, 13, 25, 26. In some circumstances, CAFO waste has been shown to increase antibiotic resistant bacteria in surface and groundwater11, 14, 17, 18, 27, 28. CAFOs emit air pollutants such as ammonia, hydrogen sulfide, particulate matter, volatile organic compounds (VOCs), and nitrous oxide29, 30, 31, 32, 33, 34, 35, 36, 37.

Studies show negative health outcomes among CAFO workers, including symptoms of pulmonary disease, lung function abnormalities38, 39, poorer respiratory health outcomes, and increased inflammatory biomarkers40, although CAFO workers may be covered by different regulations than individuals with residences near CAFOs. Available evidence also suggests negative health effects for those living near CAFOs, such as increased risk of mortality, specifically cardiovascular mortality41; respiratory outcomes42 such as allergies and asthma43; respiratory illnesses; and increased incidence of chest tightness, wheezing, coughing, nausea, fainting, headache, and plugged ears, compared to those living further from CAFOs39, 44. A study which reviewed adults’ electronic medical records finds living near a CAFO is associated with increased asthma-related hospitalizations and asthma medication use45. Children living near or attending schools near CAFOs also appear to have higher prevalence of asthma40.

A review that included studies from Europe finds living close to industrial animal food production or manure-applied fields is associated with contraction of methicillin-resistant Staphylococcus aureus (MRSA) and the bacterial illness Q-fever42. A North Carolina-based study finds communities near CAFOs appear to have higher all-cause and infant mortality, higher rates of hospitalizations for low birthweight infants, and increased incidence of other diseases and illnesses46. Although another analysis of this data suggests CAFOs’ role in North Carolina is unclear given the systemic, underlying health disparities in communities near CAFOs47. CAFO neighbors more commonly report increased anger, depression, fatigue, stress, sore throat, diarrhea, and burning eyes38, 39. CAFO odors spur decreases in reported quality of life among neighbors38. CAFOs also appear to negatively affect nearby housing prices, especially for homes within a 3-mile radius48, 49.

Greenhouse gas emissions from CAFOs contribute significantly to climate change50. A Michigan and North Carolina-based study suggests that CAFOs are associated with loss of nearby savanna, forest, and wetland, compared with areas that do not have CAFOs51. Practices to grow animals larger and with more meat, such as chickens, contribute to increased manure and pollution amounts50. Flooding and hurricanes can cause waste stored in open-pit lagoons to spill into local watersheds. For example, in North Carolina, hurricanes in 1999 and 2018 led to trillions of liters of waste overflowing into waterways, along with thousands of dead hogs50. CAFOs often use many acres of surrounding land for manure application, which exceeds the soil’s nutrient needs, so this application should not be viewed as fertilizer but as waste disposal51. Melting snow and increased precipitation can also increase runoff from CAFOs’ lagoons and land where CAFO manure is applied21. Critically, this runoff is classified as non-point source pollution, so is mostly exempt from federal Clean Water Act regulation21.

State differences in permitting and defining pollutants and discharge mean that many states have many unpermitted CAFOs. CAFOs are also often defined as minor dischargers and so are not required to systematically report discharges to the EPA or state agencies, presenting challenges in measuring compliance with National Pollution Discharge Elimination System (NPDES) regulations. NPDES permits may not necessarily regulate how much waste is spread onto fields. Experts note that non-point source pollution is difficult for states to regulate, with most states recommending best management practices or setting thresholds for nutrients in surface waterbodies21, 52. A Wisconsin-based study finds that farms which expand to become CAFOs appear to significantly increase total phosphorus downstream and recommends water quality standards that focus on nutrient loads and monitoring schedules that include peak precipitation events53. Experts recommend increased focus on limiting runoff by siting CAFOs strategically, limiting CAFO size, and improving farming practices, particularly in spring and summer, to reduce nutrient loads, especially as extreme rainfall events become more frequent with climate change53. Models suggest that CAFO regulations based on downstream emissions are more cost-effective for producers than quantity controls or limits for field manure applications, especially with technology to reduce emissions54. Regulations can encourage CAFOs to adopt technology to capture methane emissions for renewable energy, which can help to mitigate climate change effects5, 55, 56, 57.

Adequate funding for oversight, research, and enforcement are key to implementation of effective regulations26. However, federal regulation and oversight appear to have decreased between 2011-202050. States’ differences in permitting, legal regulation, data collection, and data transparency mean that states and the EPA lack complete information about CAFOs and estimates suggest there may be 15 percent more CAFOs than reported50. Researchers also suggest that relying on size-based regulations alone may have limited effects on small farms and may encourage large farms to downsize to avoid regulation21, 58. Recent research suggests the number of smaller CAFOs is increasing50. More research is needed to compare effects of living near many small AFOs with effects of living near a single large CAFO.

CAFOs may present a greater risk of being the source of zoonotic disease outbreaks, for example, strains of influenza, due to the facilities’ size and number of animals. Experts recommend mitigating risks through standardized and operation-specific biosecurity and waste management practices and improved, complete communication between CAFOs, governing agencies, health services, animal services, researchers, and consumers59.

How could this strategy advance health equity? This strategy is rated potential to decrease disparities: suggested by expert opinion.

State or local confined animal feeding operation (CAFO) regulations are a suggested strategy to reduce disparities in negative health outcomes and environmental contamination experienced by rural communities, particularly those with lower incomes or a higher proportion of individuals of color43, 75, 76, 77. In 2019, the American Public Health Association (APHA) called for a precautionary moratorium on new CAFOs and CAFO expansion until regulation and enforcements are in place to protect public health, arguing that CAFOs unjustly and disproportionately affect communities with lower incomes and with higher proportions of residents belonging to racial and ethnic minority groups77.

CAFOs are typically located in rural areas. In several areas of the country, such as North Carolina and Mississippi, CAFOs have been found to be clustered in low income, minority communities, raising environmental justice concerns78, 79. In Oregon, the state’s two largest CAFOs are located in a county with a Latino/a population over twice Oregon’s average63. Recent analyses still find CAFOs in Mississippi are more likely to be in census tracts with an average or greater number of Black residents, compared to the rest of the state, though the number of swine CAFOs and hogs present in Mississippi has declined since an analysis done in 2002, possibly related to a meat processing plant closure80. Individuals of color in North Carolina and California are more likely to live within 3 miles of a large CAFO, compared to non-Hispanic white residents. Communities with low levels of wealth are also more likely to have CAFOs nearby. In Iowa, 81 percent of individuals in census tracts experiencing the most poverty live near a CAFO; in California, 27 percent, and in North Carolina, 25 percent75, 81. In Delaware and Maryland, individuals living in poverty are more likely to live in areas with many poultry CAFOs, compared to the rest of the state, and areas with higher median income are associated with a reduced number of CAFOs82, 83. Experts suggest with the growth of CAFOs, a lot of the wealth produced in rural areas stopped being re-invested locally, so many rural areas have also been experiencing economic declines as environmental and health problems grow84.

Experts suggest that large livestock farms be regulated as they potentially contribute to health disparities among rural individuals43. A study of individuals living near dairy CAFOs in Wisconsin finds living within a few miles of a CAFO is positively associated with reduced lung function, and self-reported asthma and respiratory allergies43. A North Carolina-based study finds living near CAFOs is associated with increased rates of acute gastrointestinal illness, particularly for Native and Black rural residents, with a stronger association following heavy rain and in areas with poultry and swine CAFOs76.

In many cases, the vast quantities of water used by CAFOs conflict with Native nations’ water rights and increase environmental injustices among Native populations63.

What is the relevant historical background?

CAFOs in the U.S. were initially developed in the 1950s and began an era of transition from small, higher-cost farms to much larger farms with lower operating costs and increased efficiency, leading to a global spread of CAFOs by the 1990s85. In some states, CAFOs make up a small portion of overall AFOs but house an increasing percentage of animals, as in Wisconsin, where a small percentage of dairy CAFOs hold a quarter of the state’s cattle21. In Iowa between 1980-2002, the number of hog farmers decreased from 65,000 to 10,000 but the number of hogs being raised increased from 13 to 14 million20.

States passed right-to-farm laws, mostly in the early 1980s with support from agricultural interest groups, and statutes now exist in all 50 states. Traditional right-to-farm laws (not zoning-based) focus on protecting agricultural operations from public nuisance lawsuits brought by community members or the state, most often against livestock operations. In states such as Wisconsin, laws were developed in response to large farms (e.g., an egg farm with 140,000 chickens that spread 15 tons of manure daily) being found a nuisance and ordered to close; the new law defined nuisance as a substantial threat to health and safety and prevented changes in agricultural land use or scale from being considered in nuisance decisions. Since 2017, some states’ farm bureaus and agricultural lobbies have successfully supported passage of bills amending right-to-farm laws, as in North Carolina, West Virginia, Oklahoma, and Utah, in response to lawsuits against hog farms in North Carolina where plaintiffs were awarded significant damages. Punitive damages, which may be the bulk of awards, have been reduced or eliminated – in some cases, so much that a plaintiff may not be able to cover their legal fees67. In contrast, Minnesota’s law excludes animal feedlots above a certain size, does not protect agricultural activity for two years after it starts or undergoes significant change, and defines a potential public nuisance more broadly as annoying, injuring, or endangering the safety, health, morals, comfort, or repose of any considerable number of members of the public67.

With the spread of CAFOs, nitrogen and phosphorus pollution, which is correlated with eutrophication and harmful algal blooms, has been increasing since the 1970s and has now been documented in every state, including freshwater and coastal waters50. The contribution of CAFO waste to antibiotic resistance in bacteria in surface and groundwater11, 14, 17, 18, 27, 28 is concerning, given that the World Health Organization reports that globally, high levels of antibiotic resistance in bacteria are causing increases in life-threatening blood infections as well as increases in common infections resistant to treatment in humans86.

Federal oversight of CAFOs began with the Clean Water Act of 1972 which established the U.S. EPA’s National Pollution Discharge Elimination System (NPDES) and was updated with new rules in 2003 and 200852. However, federal inspections and enforcement of regulation has declined from 2011-202050. Congress has eliminated some reporting requirements and has not implemented final methods to estimate CAFO emissions. In 2018, the U.S. Congress passed legislative changes to the Fair Agricultural Reporting Method (FARM) Act to include large CAFOs as exempt from reporting air emissions from animal waste – previously large CAFOs had been required to report per 2008 law87. Reporting is intended to alert federal, state, and local officials if hazardous substances have been released beyond a certain threshold and mitigation is needed to protect the community87. The number of CAFOs in the U.S. has increased almost 10 percent since 2012, due mostly to increased hog production50.

The term “family farm” includes many large farms, AFOs, and CAFOs. While 98 percent of farms globally are family-owned, smallholder farms (under 2 hectares, or just under 5 acres) cover only 24 percent of gross agricultural land88. According to data from 55 countries, researchers estimate that these smallholder farms manage to produce 28-31 percent of global crops and 30-34 percent of global food supply88. However, an analysis of farm consolidation from 1969-2013 predicts that farm consolidation will continue globally, with the number of farms overall continuing to decrease and average farm size doubling89. Consolidating farms can increase labor productivity and economic growth, though it also concentrates corporate power in the food system, may increase food waste, and may not improve conditions for workers. Larger farms are more likely to be monocultures and have less biodiversity, which increases vulnerability to climate change and pests and threatens overall food system stability and resilience88, 89. Large farms could, however, be designed to have more biodiversity, smaller farms’ nutrient use efficiency could be increased, and policies enacted to maintain indigenous knowledge and plan urban spaces to maintain communities’ connection to land, despite fewer individuals working directly with agriculture89.

Equity Considerations
  • Where are CAFOs sited in your county or state? What efforts – past or current — are attempting to ensure CAFOs are sited equitably, by business owners, communities, or regulators?
  • Who monitors CAFO environmental and health impacts in your state? Are CAFOs in your community required to monitor or report beyond federal or state standards?
  • Who doesn’t want CAFO regulation in your community? Why? What role do residents play in decision-making about agricultural expansion in your community? What pathways exist for residents to take an active role?
  • Are there measures in place to ensure CAFO profits support the local community and its resources, including environmental protections?
Implementation Examples

Some states’ regulations are broad in scope with detailed definitions and designated enforcement support, while others simply comply with federal requirements4. For example, Maryland Animal Feeding Operations (MAFOs) are a special category and must have a general (water) discharge permit, to ensure all possible point discharge sources are regulated, not only protected surface waters. Maryland state law also defines pollutants as including gaseous substances (e.g., gaseous ammonia), in addition to solid and liquid waste, which is broader than the federal interpretation of the Clean Water Act60. As of 2022, permit applicants to Maryland’s Department of the Environment are required to include an environmental justice score (which indicates pollution burden, sensitive populations, and socioeconomic factors), using the Maryland EJ Tool or the tool from the U.S. EPA61.

As of 2023, some state legislatures are considering bills prohibiting new or expanding CAFOs, as in Oregon62. A 2007 bill passed by Oregon’s legislature created a task force to study and reduce air emissions from dairy CAFOs, but the task force’s recommendation to fund an Oregon Dairy Emissions Program for further research and to design interim regulatory measures were not adopted as of 202163. Some states also have grassroots coalitions which advocate for regenerative farming practices, equitable working conditions, and high environmental and animal welfare standards, for example, the Michiganders for a Just Farming System coalition that includes farmers, individuals, and organizations64. The organization Natural Resources Defense Council (NRDC) has produced a map illustrating the transparency of states’ CAFO data, meaning whether CAFOs hold permits, their type and location, manure storage practices, and ownership. Only Maryland and Tennessee are rated as having high transparency for this type of information65.

The National Agricultural Law Center (NALC) compiles information on states’ Right to Farm statues66. Some states, such as Wisconsin, North Carolina, West Virginia, Oklahoma, and Utah, more strongly restrict what is considered a public nuisance and have eliminated or reduced the economic damages that plaintiffs can be awarded. Other states, such as Minnesota, more broadly define public nuisance and limit right to farm protections for large feedlots and new agricultural operations or those that have undergone significant changes67. However, despite Minnesota’s efforts, counties in its Southeastern Karst Region are experiencing groundwater nitrate contamination. In 2023, the EPA recommended that the state of Minnesota adopt monitoring requirements as part of issuing its NPDES and related permits – for example, to monitor discharges related to land application of manure, as is done on CAFOs. Similar guidance was issued to Idaho to modify its permits68. Landscapes with karst terrain are especially vulnerable to contamination, are present across the continental U.S., and supply about 40% of groundwater used for drinking69. The U.S. Geological Survey (USGS) has maps of karst aquifers69.

In states with preemption legislation, communities and municipalities can shift from deterrence-based efforts to partnerships with industry and voluntary programs that educate producers about practices to minimize pollution discharge and enhance pollution controls70. In all states, local boards of health can increase water and air quality testing in the areas surrounding CAFOs; and in some areas, local boards of health can also pass ordinances or regulations directed at CAFOs5. At the federal level, in June 2023 Representative Rosa DeLaura from Connecticut reintroduced the Expanded Food Safety Investigation Act, which would give the FDA and CDC authority to do microbial sampling at CAFOs for the sources of foodborne illness – currently, CAFOs can refuse71.

The U.S. EPA has been working to develop CAFO emission estimation methodologies (EEMs) since 2005. CAFOs were allowed to pay small penalties – $2k or less – to fund the EPA’s study of CAFO emissions and support development of the EEMs. In exchange, around 14,000 farms (an AFO can include multiple farms) have been protected (far longer than anticipated) from being sued by the EPA for violating the Clean Air Act until the EEMs are established. However, delays led to draft EEMs not being published until 2020, 11 years after the 2009 deadline. The EEMs are scheduled to be finalized in 202372.­­

The U.S. Department of Agriculture’s Natural Resource Conservation Service supports voluntary adoption of comprehensive nutrient management plans to reduce nutrient run-off, which have stronger protections for natural resources than other nutrient management plans73.

In 2022, a nationwide coalition of citizens’ groups and advocacy organizations petitioned the EPA to increase oversight of CAFOs in accordance with the Clean Water Act, asking that large CAFOs with wet manure management systems (most large swine and dairy CAFOs) be required to get water pollution discharge permits74. The petition argues that the EPA acknowledges that CAFOs discharge water pollution but allows most large CAFOs to operate without federal-law permits, which offer stronger protection of water quality, more transparency, and more opportunities for public participation, compared with state-law permits74.

Implementation Resources

Resources with a focus on equity.

NALC-Right to Farm Statutes - National Agricultural Law Center (NALC). States’ Right to Farm Statutes.

US EPA-NPDES AFOs - U.S. Environmental Protection Agency (U.S. EPA). National pollutant discharge elimination system (NPDES): Animal feeding operations (AFOs).

US EPA-How’s My Waterway - U.S. Environmental Protection Agency (U.S. EPA). How’s My Waterway?

MEA-Legal action guide 2013 - Midwest Environmental Advocates (MEA). Protecting your community from existing and proposed concentrated animal feeding operations (CAFOs): A guide to legal actions. 2013:4-8.

UCS-Gurian-Sherman 2008 - Gurian-Sherman D. CAFOs uncovered: The untold costs of confined animal feeding operations. Cambridge, MA: Union of Concerned Scientists (UCS); 2008.


* Journal subscription may be required for access.

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7 ERS-Sneeringer 2013 - Sneeringer S, Key N. Effects of CAFO regulations on livestock producers’ behaviors. 2013 AAEA & CAES Joint Annual Meeting. Washington, D.C.: Agricultural and Applied Economics Association (AAEA); 2013.

8 Brands 2014 - Brands E. Siting restrictions and proximity of Concentrated Animal Feeding Operations to surface water. Environmental Science & Policy. 2014;38:245-253.

9 Lockhart 2013 - Lockhart KM, King AM, Harter T. Identifying sources of groundwater nitrate contamination in a large alluvial groundwater basin with highly diversified intensive agricultural production. Journal of Contaminant Hydrology. 2013;151(3):140-154.

10 Mallin 2015 - Mallin MA, McIver MR, Robuck AR, Dickens AK. Industrial swine and poultry production causes chronic nutrient and fecal microbial stream pollution. Water, Air, & Soil Pollution. 2015;226(12):407.

11 West 2011 - West BM, Liggit P, Clemans DL, Francoeur SN. Antibiotic resistance, gene transfer, and water quality patterns observed in waterways near CAFO farms and wastewater treatment facilities. Water, Air, and Soil Pollution. 2011;217(1):473-489.

12 Whalen 2007 - Whalen SC, DeBerardinis JT. Nitrogen mass balance in fields irrigated with liquid swine waste. Nutrient Cycling in Agroecosystems. 2007;78(1):37-50.

13 Adeel 2017 - Adeel M, Song X, Wang Y, Francis D, Yang Y. Environmental impact of estrogens on human, animal and plant life: A critical review. Environment International. 2017;99:107-119.

14 Bartelt-Hunt 2011 - Bartelt-Hunt S, Snow DD, Damon-Powell T, Miesbach D. Occurrence of steroid hormones and antibiotics in shallow groundwater impacted by livestock waste control facilities. Journal of Contaminant Hydrology. 2011;123(3-4):94-103.

15 Gentry-Shields 2015 - Gentry-Shields J, Myers K, Pisanic N, Heaney C, Stewart J. Hepatitis E virus and coliphages in waters proximal to swine concentrated animal feeding operations. Science of the Total Environment. 2015.

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19 Miralha 2022 - Miralha L, Sidique S, Logsdon Muenich R. The spatial organization of CAFOs and its relationship to water quality in the United States. Journal of Hydrology. 2022;613(A):128301.

20 Jones 2019b - Jones CS, Drake CW, Hruby CE, Schilling KE, Wolter CF. Livestock manure driving stream nitrate. Ambio. 2019;48:1143-1153.

21 Raff 2022 - Raff Z, Meyer A. CAFOs and surface water quality: Evidence from Wisconsin. American Journal of Agricultural Economics. 2022;104(1):161-189.

22 Temkin 2019 - Temkin A, Evans S, Manidis T, Campbell C, Naidenko OV. Exposure-based assessment and economic valuation of adverse birth outcomes and cancer risk due to nitrate in United States drinking water. Environmental Research. 2019;176:108442.

23 Picetti 2022 - Picetti R, Deeney M, Pastorino S, et al. Nitrate and nitrite contamination in drinking water and cancer risk: A systematic review with meta-analysis. Environmental Research. 2022;210:112988.

24 Makris 2008 - Makris KC, Quazi S, Punamiya P, Sarkar D, Datta R. Fate of arsenic in swine waste from concentrated animal feeding operations. Journal of Environmental Quality. 2008;37(4):1626-1633.

25 Leet 2012 - Leet JK, Lee LS, Gall HE, et al. Assessing impacts of land-applied manure from concentrated animal feeding operations on fish populations and communities. Environmental Science & Technology. 2012;46(24):13440-13447.

26 CRS-Copeland 2010 - Copeland C. Animal waste and water quality: EPA regulation of concentrated animal feeding operations (CAFOs). Washington, D.C.: Congressional Research Service (CRS); 2010.

27 Brooks 2014 - Brooks JP, Adeli A, McLaughlin MR. Microbial ecology, bacterial pathogens, and antibiotic resistant genes in swine manure wastewater as influenced by three swine management systems. Water Research. 2014;57:96-103.

28 Barrett 2005 - Barrett JR. Airborne bacteria in CAFOs: Transfer of resistance from animals to humans. Environmental Health Perspectives. 2005;113(2):A116-A117.

29 Heinzen 2015 - Heinzen T. Recent developments in the quantification and regulation of air emissions from animal feeding operations. Current Environmental Health Reports. 2015;2(1):25-32.

30 Rumsey 2014 - Rumsey IC, Aneja VP, Lonneman WA. Characterizing reduced sulfur compounds emissions from a swine concentrated animal feeding operation. Atmospheric Environment. 2014;94:458-466.

31 Rumsey 2014a - Rumsey IC, Aneja VP. Measurement and modeling of hydrogen sulfide lagoon emissions from a swine concentrated animal feeding operation. Environmental Science & Technology. 2014;48(3):1609-1617.

32 Pavilonis 2013 - Pavilonis BT, O’Shaughnessy PT, Altmaier R, Metwali N, Thorne PS. Passive monitors to measure hydrogen sulfide near concentrated animal feeding operations. Environmental Science: Processes & Impacts. 2013;15(6):1271-1278.

33 Rumsey 2012 - Rumsey IC, Aneja VP, Lonneman WA. Characterizing non-methane volatile organic compounds emissions from a swine concentrated animal feeding operation. Atmospheric Environment. 2012;47:348-357.

34 Blunden 2005 - Blunden J, Aneja VP, Lonneman WA. Characterization of non-methane volatile organic compounds at swine facilities in eastern North Carolina. Atmospheric Environment. 2005;39(36):6707-6718.

35 Hoff 2002 - Hoff SJ, Hornbuckle KC, Thorne PS, Bundy DS, O’Shaughnessy PT. Emissions and community exposures from CAFOs. Iowa Concentrated Animal Feeding Operations Air Quality Study. 2002:45-85.

36 Wilson 2007 - Wilson SM, Serre ML. Examination of atmospheric ammonia levels near hog CAFOs, homes, and schools in Eastern North Carolina. Atmospheric Environment. 2007;41:4977-4987.

37 Ogneva-Himmelberger 2015 - Ogneva-Himmelberger Y, Huang L, Xin H. CALPUFF and CAFOs: Air pollution modeling and environmental justice analysis in the North Carolina hog industry. ISPRS International Journal of Geo-Information. 2015;4(1):150-171.

38 Von Essen 2005 - Von Essen SG, Auvermann BW. Health effects from breathing air near CAFOs for feeder cattle or hogs. Journal of Agromedicine. 2005;10(4):55-64.

39 Greger 2010 - Greger M, Koneswaran G. The public health impacts of concentrated animal feeding operations on local communities. Family & Community Health. 2010;33(1):11-20.

40 Douglas 2018 - Douglas P, Robertson S, Gay R, Hansell AL, Gant TW. A systematic review of the public health risks of bioaerosols from intensive farming. International Journal of Hygiene and Environmental Health. 2018;221(2):134-173.

41 Son 2021a - Son JY, Miranda ML, Bell ML. Exposure to concentrated animal feeding operations (CAFOs) and risk of mortality in North Carolina, USA. Science of the Total Environment. 2021;799:149407.

42 Casey 2015 - Casey JA, Kim BF, Larsen J, Price LB, Nachman KE. Industrial food animal production and community health. Current Environmental Health Reports. 2015;2:259-271.

43 Schultz 2019 - Schultz AA, Peppard P, Gangnon RE, Malecki KMC. Residential proximity to concentrated animal feeding operations and allergic and respiratory disease. Environment International. 2019;130:104911.

44 Sigurdarson 2006 - Sigurdarson ST, Kline JN. School proximity to concentrated animal feeding operations and prevalence of asthma in students. Chest. 2006;129(6):1486-1491.

45 Rasmussen 2017 - Rasmussen SG, Casey JA, Bandeen-Roche K, Schwartz BS. Proximity to industrial food animal production and asthma exacerbations in Pennsylvania, 2005–2012. International Journal of Environmental Research and Public Health. 2017;14(4):362.

46 Kravchenko 2018 - Kravchenko J, Rhew SH, Akushevich I, Agarwal P, Lyerly HK. Mortality and health outcomes in North Carolina communities located in close proximity to hog concentrated animal feeding operations. North Carolina Medical Journal. 2018;79(5):278-288.

47 Kanankege 2023 - Kanankege KST, Traynor I, Perez AM. A reanalysis: Do hog farms cause disease in North Carolina neighborhoods? Frontiers in Veterinary Science. 2023;9.

48 Isakson 2008 - Isakson HR, Ecker MD. An analysis of the impact of swine CAFOs on the value of nearby houses. Agricultural Economics. 2008;39(3):365-372.

49 Kilpatrick 2015 - Kilpatrick JA. Animal operations and residential property values. Appraisal Journal. 2015;83(1):41-50.

50 Glibert 2020 - Glibert PM. From hogs to HABs: Impacts of industrial farming in the U.S. on nitrogen and phosphorus and greenhouse gas pollution. Biogeochemistry. 2020;150(2):139-180.

51 Miralha 2021 - Miralha L, Muenich RL, Schaffer-Smith D, Myint SW. Spatiotemporal land use change and environmental degradation surrounding CAFOs in Michigan and North Carolina. Science of the Total Environment. 2021;800:149391.

52 Rosov 2020 - Rosov KA, Mallin MA, Cahoon LB. Waste nutrients from U.S. animal feeding operations: Regulations are inconsistent across states and inadequately assess nutrient export risk. Journal of Environmental Management. 2020;269:110738.

53 Waller 2021 - Waller DM, Meyer AG, Raff Z, Apfelbaum SI. Shifts in precipitation and agricultural intensity increase phosphorus concentrations and loads in an agricultural watershed. Journal of Environmental Management. 2021;284:112019.

54 Wang 2015 - Wang J, Baerenklau KA. How inefficient are nutrient application limits? A dynamic analysis of groundwater nitrate pollution from concentrated animal feeding operations. Applied Economic Perspectives and Policy. 2015;37(1):130-150.

55 Verheul 2011 - Verheul J. Methane as a greenhouse gas: Why the EPA should regulate emissions from animal feeding operations and concentrated animal feeding operations under the Clean Air Act. Natural Resources Journal. 2011;51(1):163-187.

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