Spatiotemporal patterns of surface ozone exposure inequality in China

Rising surface ozone (O₃) levels in China are increasingly emphasizing the potential threats to public health, ecological balance, and economic sustainability. Using a 1 km × 1 km dataset of O₃ concentrations, this research employs subpopulation demographic data combined with a population-weighted quality model. Its aim is to evaluate quantitatively the differences in O₃ exposure among various subpopulations within China, both at a provincial and urban cluster level. Additionally, an exposure disparity indicator was devised to establish unambiguous exposure risks among significant urban agglomerations at varying O₃ concentration levels. The findings reveal that as of 2018, the population-weighted average concentration of O₃ for all subgroups has experienced a significant uptick, surpassing the average O₃ concentration (118 μg/m³). Notably, the middle-aged demographic exhibited the highest O₃ exposure level at 135.7 μg/m³, which is significantly elevated compared to other age brackets. Concurrently, there exists a prominent positive correlation between educational attainment and O₃ exposure levels, with the medium-income bracket showing the greatest susceptibility to O₃ exposure risks. From an industrial vantage point, the secondary sector demographic is the most adversely impacted by O₃ exposure. In terms of urban-rural structure, urban groups in all regions had higher levels of exposure to O₃ than rural areas, with North and East China having the most significant levels of exposure. These findings not only emphasize the intricate interplay between public health and environmental justice but further highlight the indispensability of segmented subgroup strategies in environmental health risk assessment. Moreover, this research furnishes invaluable scientific groundwork for crafting targeted public health interventions and sustainable air quality management policies.