Heatwaves and ozone pollution together increase cardiac deaths in India: study

A peer-reviewed study has found that surface ozone concentrations reach dangerous levels during heatwaves in India, with northern regions recording 85-110 μg/m³—well above the WHO guideline of 70 μg/m³. The research indicates that ozone levels exceed WHO safety thresholds in every region of the country during extreme heat events.

Data from 2024 shows approximately 830 additional deaths were recorded during heatwave periods compared to preceding days, with the combined effect of high temperatures and elevated ozone pollution linked to increased cardiac mortality.