Air Quality Disparities and Health Impacts

Air pollution remains one of the leading environmental risk factors for human health, driving elevated rates of cardiovascular and respiratory disease across the globe. Disparities in exposure arise from a complex interplay of socioeconomic status, race or ethnicity, urban form and local emission sources. Fine particulate matter (PM2.5), nitrogen dioxide (NO2) and ozone (O3) are principal contributors to adverse outcomes, with mounting evidence that marginalised populations bear disproportionate burdens. Neighbourhood characteristics such as proximity to major roadways, levels of urban greenness and industrial zoning intensify local exposures and underlie persistent inequities. These gradients in air quality translate into measurable differences in life expectancy, avoidable mortality and chronic illness, underscoring the imperative for targeted interventions and equitable policy measures.

Research from Nature Portfolio

Recent studies have examined the potential of sector-specific interventions to alleviate disproportionate exposures. One investigation employed a high-resolution air quality model to assess the effects of electrifying 30 % of heavy-duty vehicles around a major freight hub. The shift from diesel to electric vehicles led to substantial reductions in NO2 and PM2.5, yielding hundreds of avoided premature deaths annually, yet also produced modest increases in ozone. Crucially, the greatest health benefits accrued within historically underserved Black and Hispanic/Latino communities, demonstrating how technology transitions can advance environmental justice. Another global analysis linked fine particulate exposure with poverty indices across more than 200 territories, revealing that over 80 % of people subjected to PM2.5 concentrations above World Health Organization guidelines reside in low- and middle-income settings. Among the world’s lowest-income households, more than 700 million individuals inhabit areas with unsafe levels of particulate pollution, notably across Sub-Saharan Africa and parts of South Asia, emphasising the intersection of poverty and air quality risk on a planetary scale.

Air Quality Disparities and Health Impacts publication trend

The graph below shows the total number of articles in air quality disparities and health impacts across all publications each year (not limited to Nature Index journals).

Technical terms

Fine particulate matter (PM2.5): Atmospheric particles with aerodynamic diameters of 2.5 micrometres or less, capable of penetrating deep into the lungs and bloodstream.

Nitrogen dioxide (NO2): A gaseous pollutant primarily emitted by combustion engines and industrial processes, linked to respiratory inflammation and increased cardiovascular risk.

Ozone (O3): A secondary pollutant formed by photochemical reactions of precursors such as nitrogen oxides and volatile organic compounds, associated with respiratory distress and reduced lung function.

References

1. Ambient nitrogen dioxide in 47 187 neighbourhoods across 326 cities in eight Latin American countries: population exposures and associations with urban features. The Lancet Planetary Health (2023).
2. Air quality, health and equity implications of electrifying heavy-duty vehicles. Nature Sustainability (2023).
3. Global air pollution exposure and poverty. Nature Communications (2023).
4. PM2.5 polluters disproportionately and systemically affect people of color in the United States. Science Advances (2021).