New Delhi: Waste burning has now become one of the top sources of Delhi’s air pollution. According to new real-time source apportionment data, waste burning — municipal, plastic, rubber-containing waste — was the top contributor to the city’s air pollution Tuesday at 20.4%, while vehicles occupied the second position at 19.6%.The share of waste burning Monday was 18.4%, second after vehicles. Between Oct 22 and 26, the daily contribution of waste burning was less than 5%, but its daily share rose significantly in the past two days. It is expected to rise further during the winter months.Indian Institute of Tropical Meteorology’s new laboratory, Integrated Atmospheric Chemistry and Aerosol Toxicity Analysis Laboratory, was inaugurated on Oct 24 at New Rajendra Nagar and provides real-time source apportionment data.Burning of garbage, wood, and garden and plastic waste is one of the major sources of pollution in Delhi in winter. While waste burning was the dominant source of PM2.5 Tuesday, the contribution of roadside or open biomass burning — leaves, grass, vegetation, small biomass piles — was 2.6%, wood burning 2.5% and dung-cake burning 2.2%.Sunil Dahiya, founder of think tank Envirocatalyst, said the study confirmed waste burning as a consistent contributor to Delhi’s winter air pollution, which was entirely local and preventable. “Fixing this needs implementation, not more advisories,” he pointed out. “Municipal Corporation of Delhi (MCD) must publish ward-level daily mass balances of waste generated, collected and processed, so the gaps that end up burnt become visible. Segregation and decentralised composting should be enforced, starting with bulk generators.”Dahiya added that open burning must be penalised year-round, not only under Graded Response Action Plan, and National Clean Air Programme funds must be tied to measurable cuts in burning incidents.Anumita Roychowdhury, executive director of research and advocacy at Centre for Science and Environment, said Delhi’s waste burning reflected inadequate efforts to fulfil Swachh Bharat Mission goals of universal segregation, collection, material recovery and legacy site remediation.“Until these systems fully mature, unsegregated waste accumulates in public spaces that are vulnerable to open fires. This requires strong accountability for city-wide efficient waste collection and segregation systems in both formal and informal settlements, building advanced material recovery facilities that also integrates informal recyclers, guarantees industrial off-takers for processed fractions, and provides clean winter heating to low-income groups alongside proactive neighborhood monitoring,” said Roychowdhury.In 2025, MCD issued 784 challans for open or biomass burning and imposed a penalty of Rs 8.7 lakh, against 191 challans and Rs 4.4 lakh in penalties in 2024.“Under the winter action plan, MCD has constituted joint enforcement teams. These teams monitor and inspect biomass burning, dust pollution arising from construction and demolition activities, use of unauthorised fuels, illegal dumping of C&D waste or garbage, and C&D waste storage or dumping sites,” said a civic official. He added that 623 staff had been deployed in enforcement teams and 600 in teams at the ward level.