Delhi is once again grappling with deteriorating air quality as winter sets in, with the Air Quality Index (AQI) surpassing 300 and entering the "very poor" category. This situation raises health concerns for millions of residents, as prolonged exposure to such polluted air can lead to respiratory issues and exacerbate existing health conditions, particularly affecting children and the elderly.
In response, authorities have activated Stage II of the Graded Response Action Plan (GRAP), implementing measures to control dust, vehicle emissions, and other pollution sources. This annual winter pollution crisis, a familiar challenge for Delhi and northern India, is often intensified around Diwali, a major Indian festival.
The festival's traditions, which include the use of fireworks, historically contribute to the worsening air quality by releasing fine particles and harmful gases into the atmosphere. Last year, the city experienced a toxic haze following Diwali celebrations, despite court directives aimed at promoting the use of less-polluting firecrackers.
The Supreme Court has permitted the use of certified green firecrackers for limited periods during Diwali weekend, specifically between 06:00 and 07:00 and 20:00 and 22:00 on November 7 and 8. These green crackers are designed with modified chemical formulations to reduce emissions and must feature QR codes for verification. The court also mandated a ban on fireworks within 300 meters of hospitals, care homes, and schools.
However, enforcing these regulations and preventing the sale of conventional firecrackers as alternatives remains a significant challenge. Authorities have been directed to patrol sales areas, conduct random QR-code checks, and seize illegal firecrackers.
The current spike in pollution follows an unusually clean October for Delhi, which recorded its lowest average AQI for the month in eight years. Experts attribute the recent deterioration to a combination of factors: falling temperatures, slow wind speeds, and an increase in crop-residue burning in neighboring states like Punjab and Haryana. While a recent storm temporarily improved air quality with rain and stronger winds, the return of north-westerly winds has begun carrying smoke from agricultural fields toward the capital.
Pollution is not limited to Delhi. Mumbai, India's financial hub, has also experienced elevated pollution levels, with its AQI reaching 322 in the "very poor" category on October 24. This spike was attributed to low wind speeds, construction dust, garbage burning, and pollutants carried from nearby regions. The city's air quality has since improved, with its AQI dropping to 89, classified as "satisfactory," on Wednesday. In contrast, Navi Mumbai recorded a "moderate" AQI of 118.