The Environmental Protection Agency’s air quality monitors are disproportionately positioned in whiter neighborhoods in the US, leaving communities of color less protected from dangerous pollutants like particulate matter, ozone, nitrous dioxide and lead, among others, new research finds.
Policy and actions the EPA takes to reduce pollution are developed from the monitors’ readings, and communities of color are broadly more likely to be near major polluters. The findings raise questions about whether the agency has enough monitors installed, is properly placing them, and whether conclusions about the safety of the air in some areas are sound.
“It seems like an obvious problem, but we don’t see much about … how there’s a measurement error in the gold standard for data collection,” said Brenna Kelly, a University of Utah doctoral student and study co-author. “It’s how we establish thresholds for safety, and who’s going to be susceptible to exposure to air pollution.”
The researchers checked the position of nearly 8,000 EPA monitors nationwide and compared their locations with census block data.
The study consistently found a lower average of monitors for particulate matter, ozone, nitrous dioxide and lead across all non-white groups. The chemicals are linked to a range of health effects like asthma, chest pain, cardiovascular disease, neurotoxicity in developing children, and cancer.
It found the highest disparity in monitors for sulfur dioxide in Native American and Pacific Islander groups. Sulfur dioxide is a common emission during natural gas and petroleum extraction, oil refining and metal processing. It can cause difficulty breathing and exacerbate other respiratory issues.
EPA’s monitors’ positions are determined by federal, state and local authorities, the study noted, though Kelly said there was not a clear process in place for determining where to locate a monitor. Variables such as population density and concentration of polluters factor into the decision.
However, the process “can get pretty political”, Kelly added. Communities with more resources and political power may be able to sway the process, which may partly explain the disparity. The issue is also probably part of “institutionalized racism” in the decision-making process – marginalized groups typically receive fewer resources, Kelly added.
The EPA’s monitors work by measuring a single point that is meant to be a representative sample of a larger region around it. The agency estimates broader regional air quality by using some form of interpolation, but this approach can leave significant gaps. The spaces and gaps seem to generally be inhabited by communities of color.
Monitoring could be improved by using satellite imagery, the study notes. It can capture pollution across a region, but it also has limitations and would need to be deployed along with air monitors near the ground.
“That’s the big question: ‘How do we get better data?’” Kelly said. “The dream is that we understand air pollution in every area at all times, how people move throughout their environment and how that changes what they’re exposed to.”
