Investigating inequalities in NO2 air pollution concentrations on novel indicators relating to small spatial areas

Nitrogen dioxide (NO2), a significant air pollutant from transport-related fossil fuel combustion, presents a critical environmental health challenge. This study analyses NO2 trends in Ireland from 2010 to 2020, leveraging the country’s low-pollution baseline as a unique case study to analyse inequalities in NO2 concentrations across the country. Data at a small area level from Census 2022 were integrated with measurements of NO2 concentrations to assess environmental inequalities across novel indicators such as housing tenancy and self-rated health alongside conventional socioeconomic measures. The research uncovers clear evidence of environmental inequalities in NO2 concentrations, with higher levels found in neighbourhoods with larger proportions of non-white populations and non-owner-occupied housing. A stratified urban-rural analysis shows these disparities were most pronounced in urban areas. A U-shaped relationship between NO2 levels and deprivation, educational attainment, and skills, suggests that while the most and least deprived may experience similar NO2 concentrations, the health burden on disadvantaged groups may be amplified by co-occurring vulnerabilities. These findings underscore an urgent need for targeted interventions to mitigate the disproportionate burden of NO2 air pollution on vulnerable communities in Ireland.