Lucknow/Meerut, Nov 14 : The air pollution levels in towns across Uttar Pradesh, within the Delhi-NCR region, escalated to the 'severe' category after the Diwali celebrations. The Supreme Court's ban on the sale of prohibited firecrackers proved ineffective as people burst crackers with gay abandon. Post-midnight, the Air Quality Index (AQI) soared to 500 in numerous districts of the Meerut zone, including Noida, Ghaziabad, Meerut, Muzaffarnagar, Bulandshahr, Baghpat, and Hapur. Despite restricted availability in the open market, people could access crackers easily. The bursting of crackers continued well past midnight in almost all districts of the state. Diwali festivities contributed to the resurgence of smog. The AQI is determined by evaluating the levels of primary and harmful pollutants, specifically particulate matter such as PM 2.5 and PM 10, in the air. Health experts emphasized that the 'severe' category adversely affects not only individuals with existing health conditions but also healthy individuals. It is noteworthy that the GRA (Graded Response Action Plan), is in place in the region which has led to the immediate ban on all construction activity to keep the pollution levels down. 'Over the past decades, Chronic Obstructive Pulmonary Disease (COPD), primarily caused by elevated pollutant levels, has surpassed other diseases in terms of prevalence. The amount of pollution that a non-smoker in Delhi-NCR is inhaling is equivalent to 20-25 cigarettes per day. This not only aggravates prevailing asthma among patients but also adds new patients every year. Something needs to be done collectively by the civil society and governments to mitigate this crisis,' said Dr V. Tomar, a renowned pulmonologist. Describing COPD as a preventable and manageable lung disease, Dr Tomar explained that it involves inflammation and narrowing of the airways (chronic bronchitis) and damage to air sacs (emphysema). /IANS