Firecrackers release a mix of harmful pollutants, including particulate matter (PM2.5), sulphur dioxide, and nitrogen oxides, into the air. These pollutants can linger for hours or even days, leading to poor visibility and health risks. According to Climate Trends’ analysis of CPCB data, Delhi's PM2.5 levels after Diwali 2025 reached 488 µg/m³, far exceeding safe limits. Such pollution can exacerbate respiratory issues and other health problems, especially for vulnerable groups.