LUCKNOW, Oct. 20 -- Even before Diwali fireworks begin, air quality across several cities in Uttar Pradesh has sharply deteriorated, with at least four cities recording higher pollution levels than the national capital, according to the Central Pollution Control Board (CPCB) bulletin released at 4 pm on Saturday.

CPCB classifies AQI between 0-50 as Good, 51-100 as Satisfactory, 101-200 as Moderate, 201-300 as Poor, 301-400 as Very Poor, and above 400 as Severe.

The data shows Ghaziabad (AQI 333), Noida (329), Hapur (306) and Baghpat (300) all falling in the Very Poor or upper Poor category, surpassing Delhi's AQI of 296, which itself remains firmly in the Poor range.

Other UP cities also reported concerning figures, including Greater N...