Pune has been grappling with an alarming 500% rise in ground-level ozone levels in 2024 compared to the previous year, according to a recent study by the Centre for Science and Environment (CSE). This dramatic increase positions Pune as the third most polluted city out of ten surveyed in India, highlighting severe air quality issues.
Ground-level ozone, a harmful gas generated from vehicular emissions, presents significant health risks and environmental challenges. It forms when nitrogen dioxide (NO2) from vehicle exhausts reacts with sunlight. Unlike the protective ozone layer in the stratosphere, ground-level ozone exacerbates respiratory and cardiovascular problems. Prolonged exposure to this toxic gas can lead to severe health complications, including fatalities for vulnerable groups. Director of Pulmocare Research and Education Foundation, explained that ground-level ozone adversely affects lung health, worsening conditions like asthma and leading to respiratory infections. He linked the surge in ozone levels this year to elevated temperatures and increased vehicular emissions.
According to, Head of Urban Lab at CSE, continuous ozone formation, driven by high NO2 levels, leads to dangerously high concentrations. Areas around Savitribai Phule Pune University (SPPU) are particularly affected, with elevated ozone levels persisting even at night. The study, which analysed data from the Central Pollution Control Board (CPCB) for 2020 to 2024, found that exceedances of the safe ozone limit of 100 micrograms per cubic metre occurred on 58 days this summer, reflecting a 500% increase from last year.
The recent heatwaves and rising traffic congestion have compounded the issue. Pune’s environmental challenges are exacerbated by the increasing number of vehicles and a surge in traffic density, which, coupled with extreme temperatures, worsens ozone pollution. A senior official from the Pune Municipal Corporation (PMC) indicated that while the introduction of BS-VI engines, CNG and electric buses, and metro services aims to mitigate pollution, the growing population and vehicle fleet continue to strain pollution control measures.
The study identified SPPU as the most affected area, with ozone levels exceeding safe limits for 119 days this year. Gavalinagar and Thergaon in Pimpri Chinchwad also reported high ozone levels. Despite efforts to curb pollution, including infrastructure improvements and stricter regulations, the increase in peak ozone levels by 200% since 2020 is concerning. Researchers reported that the highest eight-hour average ozone level was 212.7 µg/m³, recorded on March 22. An air pollution activist stressed the urgency of addressing the problem, particularly in traffic-congested areas like SPPU. They highlighted the need for enhanced public transport systems and stringent pollution control measures to protect vulnerable populations, including children, the elderly, and those working in high-pollution areas.
