Research published in Science Advances reveals that specific components of fine particulate matter drive profound racial and ethnic disparities in cardiovascular deaths across the United States. The study analyzed data from over 3,100 counties spanning two decades, finding that cardiovascular deaths linked to air pollution components dropped from 42,200 in 2001 to 23,500 in 2020, primarily due to reductions in ammonium and sulfate pollution.
However, these improvements have not benefited all communities equally. Non-Hispanic Black and Hispanic populations experienced significantly slower declines in attributable deaths compared with non-Hispanic white populations. Between 2001 and 2020, the relative disparity in deaths increased by 24 percent for non-Hispanic Blacks and 124 percent for Hispanics when measured against non-Hispanic whites.
The study identified distinct pollution components affecting different racial groups. Black populations face disproportionately higher exposure to black carbon and sulfate, with average exposures to black carbon running 16 percent higher and sulfate 13 percent higher than white populations. Hispanic communities experience markedly elevated exposure to black carbon, nitrate, and dust particles, with dust exposure a striking 46 percent higher than among whites.
These disparities stem from historical practices including redlining and discriminatory zoning that concentrated minority populations near pollution sources like industrial facilities and fossil fuel combustion sites. Population growth compounds the problem, with Black populations growing 22 percent and Hispanic populations expanding 65 percent since 2001, compared with just 1 percent growth among non-Hispanic whites.
The regional concentration of specific pollutants varies dramatically, with sulfate dominating the South, ammonium prevalent in California and the East North Central region, and dust concentrated in southwestern states.
See: “Spatial and racial/ethnic disparities in cardiovascular mortality attributable to PM2.5 components in the contiguous United States” (Jan 28, 2026)
