Karnal (Haryana), Oct 10 (ANI): Farmers in Punjab and Haryana have started burning of paddy crops and various North Indian states are engulfed in smog. With harvesting of paddy in full swing, the farmers have started burning crop residue to prepare their farms for the upcoming Rabi crop. Smoke from crop burning contains toxic substances, including fine particulate matter. This smoke is one of two main contributors to New Delhi's worsening air pollution scenario. While the central and state governments, and even the National Green Tribunal (NGT) have come down heavily on stubble-burning, farmers say they have no options available to avoid burning the crop residue.