New Delhi. On Diwali, the air has once again become poisonous due to fireworks and crackers in Delhi-NCR. On Monday (November 13), the next day of Diwali, the Air Quality Index (AQI) in Delhi went above 900. Despite the order of the Supreme Court, there were huge fireworks display on Diwali in the capital and crackers were burst till late night in many areas. Due to this, the effect of pollution reduced due to rain was also lost and the air became poisonous again. There is a black smog in the capital due to the smoke of firecrackers.