Multi-time-scale surface ozone exposure and associated premature mortalities over Indian cities in different climatological sub-regions

• Published in: Air quality, atmosphere and health atmosphere and health, 2024-08, Vol.17 (8), p.1807-1823
• Main Authors: Kumar, Chhabeel, Dogra, Ashish, Kumari, Neelam, Yadav, Shweta, Tandon, Ankit
• Format: Article
• Language: English
• Subjects: Anthropogenic factors; Atmospheric Protection/Air Quality Control/Air Pollution; Chemical vapor deposition; Cities; Climate science; Earth and Environmental Science; Emissions; Environment; Environmental Health; Exposure; Health Promotion and Disease Prevention; Health risks; Monthly variations; Mortality; Ozone
• ISSN: 1873-9318; 1873-9326
• DOI: 10.1007/s11869-024-01547-w

Surface ozone (O 3 ) pollution driven by natural and anthropogenic emissions is one of the serious and potentially life-threatening issues in India, owing to associated human mortality. This study analyses the O 3 health metric and their long and short-term health effects (i.e. respiratory, cardiovascular (CVD) and all-cause) in 76 Indian cities. Firstly, the maximum daily 8-hour average (MD8A) is characterized by annual, seasonal, monthly, weekly and diurnal scales from 2020 to 2022. High ozone levels continue to be a concern in the Central, Northern, Western, and Eastern sub-regions, as over 60% of cities here exceed the WHO baseline (70 µg m − 3 ). On average, 15% of cities in Northern, Western and Central sub-regions surpass WHO grade (100 µg m − 3 ). While overall ozone concentrations decreased from 2020 to 2021, the median concentration increased in 2022. Peak ozone levels for the Northern, Western, and Central sub-regions occur between April and May, while Southern India has a monthly variation that is relatively stable. The weekdays have lower ozone levels than the weekends, with the summer weekends showing noticeable difference. Further, the long and short-term surface ozone exposure is associated with a total of 13,222 and 1944 premature mortalities respectively, showing a rise of 40%, 50% and 54% in 2022 for all-cause, respiratory and CVD mortalities respectively from 2020 levels. With a possible rise in precursor emissions and heat-wave events in the near future, a potential rise in health effects associated with O 3 exposure could be expected over the Indian region.