India, Oct. 23 -- A toxic haze engulfed the national capital as the air quality stayed in the 'very poor' category for the fourth straight day on Thursday. The 24-hour rolling average air quality index (AQI) stood at 328 (very poor) around 8am, marginally down from Wednesday. The AQI was at a season-high of 353 (very poor) at 4pm on Wednesday, Central Pollution Control Board (CPCB) data showed.

The impact of stubble burning remains negligible at present, with local pollutants combining with cross-boundary pollution from neighbouring states. The contribution of stubble burning to Delhi's PM 2.5 stood at 1.6% on Wednesday, data from the Centre's Decision Support System (DSS) showed.

Experts said while winds are picking up during the day, ...