Air Pollution Linked to Increased COVID-19 Mortality Risk in Chinese Cities

Strategic Insights -

A recent study conducted by investigators at Shantou University investigated the association between air pollutant exposure and COVID-19 mortality using a generalized additive model. The research analyzed data from 45 Chinese cities and found that certain air pollutants, such as nitrogen dioxide (NO2), were significantly associated with increased COVID-19 mortality risk. Specifically, a 10 g/m3 increase in NO2 was linked to a 28.3% rise in mortality risk. The study also found that particulate matter (PM2.5) significantly increased mortality risk only in Wuhan, while sulfur dioxide (SO2) and ozone (O3) were found to have protective effects.

Key Takeaways:

  • The study analyzed data from 45 Chinese cities to investigate the association between air pollutant exposure and COVID-19 mortality.
  • A 10 g/m3 increase in nitrogen dioxide (NO2) was associated with a 28.3% rise in COVID-19 mortality risk.
  • Particulate matter (PM2.5) significantly increased mortality risk only in Wuhan, with a relative risk (RR) of 1.212 (95% CI: 1.110-1.323).
  • Sulfur dioxide (SO2) and ozone (O3) were found to have protective effects, with O3 reducing mortality risk by up to 11.1% at certain lag periods.
  • The study's findings highlight the need to address air pollution in pandemic preparedness and call for further research on its regional impacts.
  • The investigators from Shantou University, including Songtao Wang, Tianyu Liu, Yaqian Su, Jiayuan Hao, Mu Qiao, and Suyang Liu, conducted the research and published their findings in the npj Climate and Atmospheric Science journal.

Statistics:

  • 45 Chinese cities were included in the analysis.
  • A 10 g/m3 increase in NO2 was associated with a 28.3% rise in COVID-19 mortality risk (RR = 1.283, 95% CI: 1.143-1.351).
  • In Wuhan, PM2.5 significantly increased mortality risk, with a RR of 1.212 (95% CI: 1.110-1.323).
  • Ozone (O3) reduced mortality risk by up to 11.1% at certain lag periods.

Sources:

  • (npj Climate and Atmospheric Science, 2025,8(1):1-9) - Air pollution and COVID-19 mortality in Chinese cities: insights from a multi-city analysis during the pandemic's first wave.
  • (Nature Portfolio - https://www.nature.com/npjclimatsci/)
  • (https://doi-org.sdpl.idm.oclc.org/10.1038/s41612-025-01042-8)