Ozone Pollution

In August 2024, the National Green Tribunal (NGT) issued notices to the Central Pollution Control Board (CPCB) and the Ministry of Environment, Forest and Climate Change (MoEF&CC) over the alarming rise in ground-level ozone pollution in major Indian cities.

The NGT took suo motu cognizance of the issue based on a report by the Centre for Science and Environment, highlighting the severe breach of permissible ozone levels in several metropolitan areas.
Between January and July 2024, ground-level ozone levels exceeded the permissible limit of 100 micrograms per cubic metre over eight hours in ten Indian metropolitan cities.
The Delhi National Capital Region recorded the highest number of days (176) with ozone levels above the permissible limit, followed by Mumbai (138), Pune (138), Jaipur (126), and Hyderabad (86).
Other cities like Kolkata, Bengaluru, Lucknow, Ahmedabad, and Chennai also experienced significant ozone exceedances, raising concerns about public health and environmental safety.
Ground-level ozone is formed through a chemical reaction between oxides of nitrogen and volatile organic compounds, particularly in the presence of heat, making it a common issue in urban areas with high vehicular emissions.
The tribunal highlighted the severe health impacts of ground-level ozone, including inflamed airways, increased susceptibility to lung infections, aggravated asthma, and heightened risks of emphysema and chronic bronchitis.