Gurugram, Dec. 16 -- Even as recurring waste fires continued across Gurugram, adding to already elevated pollution levels, the city's air quality worsened sharply on Monday, slipping into the "very poor" category as the Air Quality Index (AQI) climbed to 345 at 4 pm, according to the Central Pollution Control Board's national bulletin. A day earlier, the district had recorded a "poor" AQI of 291 at 4 pm. Residents from multiple sectors, including 34, 46, 52, 56, 72, 76, and 81, reported frequent garbage burning, especially during evenings and nights, which has persisted since Diwali. Hambir Singh, a commuter, noted regular fires near a vacant plot in Sector 72A. "The fires happen almost every day. They seem to time it intelligently, starting them in the evening... the smell of burning plastic lingers even in the early morning hours," he said. In Sector 52, advocate Pawan Yadav described rampant burning on a vacant plot that has become a hotspot. "Thousands of shanties nearby contribute to the fires... This plot, which used to be a playground for children, has now turned into a garbage dumping ground," he said, adding that private monitors show higher AQI levels and serious health risks. In Sector 76, resident Praveen Kumar said people light fires with wood and plastic for warmth. "I have personally asked some of them to stop, but they don't listen. Every little bit of pollution adds up," he said. Health experts, meanwhile, cautioned against the dangers of exposure to smoke from waste fires. Dr Arun Chowdary Kotaru, Unit Head and Senior Consultant, Respiratory Disease, Artemis Hospitals, said, "When you burn trash the smoke is toxic and has harmful gases and tiny particles that get into your lungs easily." He said short-term exposure can cause headaches, nausea, coughing and breathing difficulties, while repeated exposure can damage lungs, lower immunity and increase the risk of asthma, bronchitis and heart disease. He added that children may experience reduced lung growth, adults increased fatigue, and senior citizens a higher risk of breathlessness and infections. A senior Haryana State Pollution Control Board official, in response, said, "We have instructed our teams to increase patrolling in areas with frequent waste fires and issue fines." Meanwhile, Ravinder Yadav, additional commissioner of the Municipal Corporation of Gurugram, said civic teams were acting on identified hotspots. "We have taken a note of several waste burning hot spots across Gurugram. Our teams are working towards it. We are imposing heavy fines as well on individuals caught burning waste. Residents can also report us on CM window or through social media," he said. On Monday evening, localized AQI readings included Sector 51 at 393 and Vikas Sadan at 325, with PM2.5 as the dominant pollutant. Gurugram ranked as the fourth most polluted city in Delhi-NCR....