Read the full story from the Midwest Center for Investigative Reporting.
According to a 2017 report from the office of the inspector general, there are currently 450,000 animal feeding operations in the U.S. The majority contain less than 300 animals, but approximately 18,000 raise thousands of animals.
Air pollution from those operations can create numerous respiratory health problems, such as asthma, and contribute to climate change.
In addition to methane, a potent greenhouse gas, concentrated animal feeding operations, also called CAFOs, emit ammonia, hydrogen sulfide, particulate matter and volatile organic compounds according to a 2014 Centers for Disease Control report.
Concerned residents face an uphill battle in a regulatory environment that often favors the agriculture industry.