Concentrated animal feeding operations (CAFOs) are increasing in the U.S., raising significant concerns for animal welfare and environmental justice. These operations, often located near low-income and minority communities, cause serious human health issues via pollution of air, soil, and water by large amounts of animal waste and emissions. Research on the impact of CAFOs on human health has been limited. This study sheds light on this growing area of additional concern.

The study examined the mortality risk caused by CAFOs for people living within a 15-kilometer radius of these operations in North Carolina from 2000 to 2017. This distance covers the possible range of manure and emission transport from CAFOs. Data was obtained from the North Carolina State Center for Health Statistics, the 2010 Census, and from permitted CAFO facilities from the North Carolina Department of Environmental Quality. Those living near at least one CAFO in the study included higher percentages of Non-Hispanic Black individuals, adults with lower education, low-income households, residents of rural areas, and people living in coastal plains.

Using logistic regression models, the study compared the risk of death between people living within and beyond 15 km of at least one CAFO. Additionally, those who did live close to a CAFO were categorized into three different levels of intensity of possible impact, or “exposure,” based on the number of CAFOs within their buffer zone: low (less than three CAFOs in the zone), medium (three to seven CAFOs), and high (eight or more CAFOs). There was an average of 12 CAFOs in a 15 km buffer, though the number rose to 247 CAFOs for some buffer zones. The study focused on five different primary causes of human death: cardiovascular disease, respiratory disease, asthma, anemia, and kidney disease.

The researchers found that CAFOs are strongly linked to a higher risk of death, with a statistically significant link to a higher risk of cardiovascular disease death in particular. Cardiovascular disease accounted for 33.5% of all the deaths covered in the study. There was also a trend towards more anemia and kidney disease deaths in the “high exposure” group of people. There was no statistically significant difference between types of individuals or their backgrounds and a risk of death from CAFO exposure.

This research is limited as it didn’t consider additional possible causes of death that could have impacted the results, such as a person’s history of chronic disease, smoking habits, community-level resources, or weather conditions. Nor did the study consider exposure to CAFOs that individuals may have had from their jobs. The CAFOs examined were also limited to regulated operations, and the study didn’t cover many dry waste management operations. Farmed birds CAFOs amounted to just 0.74% of the CAFOs studied, compared to 88% farmed pigs and 11% farmed cows operations.

Although further research is needed, this study shows a clear link between CAFOs and a negative impact on human health, especially cardiovascular disease mortality. The disproportionate location of CAFOs near low-income households, individuals with low education, and  Black populations also supports the environmental justice arguments developing around these operations. These already vulnerable populations face added health risks due to CAFO proximity. 

Of course, CAFOs are especially destructive to the animals involved too. The findings from this study provide a basis for advocates to push for stricter CAFO regulations. By highlighting human health concerns, advocates can argue for policies that protect the welfare of both humans and animals. A viable alternative to CAFOs needs to be established soon, ensuring a healthier environment for all.