Disparities in exposure to concentrated animal feeding operations (CAFOs) and other animal feeding operations across multiple states in USA.

Background: Animal feeding operations (AFOs), including concentrated animal feeding operations (CAFOs), pose significant environmental degradation and health risks. These facilities are often disproportionately located in disadvantaged communities, however, findings are inconsistent.

Objective: We investigated disparities in AFO/CAFO exposure across seven US states, focusing on variables related to environmental justice (EJ) and at-risk populations.

Methods: We linked AFO/CAFO data from seven states (Iowa, North Carolina, Pennsylvania, South Carolina, Texas, Virginia, and Wisconsin) to ZIP code-level census variables. We assessed exposure by calculating area-weighted number of AFO/CAFO within 15 km buffers and categorized ZIP codes into no, low, medium, and high exposure groups. Our analysis compared the spatial distributions of AFO/CAFO exposure and variables related to EJ and at-risk populations by exposure intensity.

Results: We found differences in the distributions of AFO/CAFO exposure and variables related to EJ and at-risk populations among states. In some states (e.g., North Carolina, Pennsylvania), AFOs/CAFOs were densely clustered in specific areas, while in others (e.g., Iowa, Wisconsin), they were more evenly distributed. We found disproportionate exposure to AFO/CAFO in disadvantaged communities such as communities with high percentages of racial/ethnic minority persons and low socioeconomic status in some states, whereas other states showed different patterns. Trends varied by state, with some showing increasing Non-Hispanic Black and Hispanic populations with higher exposure (e.g., North Carolina), while others showed opposite trends (e.g., Pennsylvania). Education, poverty, and income levels also varied, with some states (e.g., North Carolina, South Carolina) showing higher poverty rates, lower education level, and lower incomes in higher exposure groups and other states showing reverse trends (e.g., Wisconsin).

Impact: This study investigated disparities in AFO/CAFO exposure across seven US states. We applied an advanced exposure metric and considered multiple variables to capture diverse aspects of environmental injustice and disadvantaged communities. Our findings across multiple states provide valuable insights that can inform policy development and help mitigate exposure disparities across various populations and locations.