This has been an everyday occurrence in the sector for the past six months. The smoke is the result of the burning of PVC coated wire to extract the metal inside by rag-pickers from the adjoining Kishangarh village.

``We feel choked, can't breath and at times even get headache,'' said C.G Sibbal, resident of Sector A, whose house is next to the empty plot, which is DDA land, but is now lined with plastic bags and filth.

Yesterday, things reached a flash-point when the residents tried to stop the rag-pickers from burning these wires. ``I had to go and douse the fire with the help of mud, but these people insisted that they would continue to burn the wires because it was their source of livelihood,'' said Sibbal. The traces of burnt wire and plastic bags were visible today.

``We are going to lodge an official complaint with the police soon if this does not stop,'' said Harminder Singh, vice president of the Welfare Association of the block, which has nearly 1,500 houses. Already the residents have to close their doors and windows every day to prevent the smoke from entering their homes.

According to experts, the smoke contains lethal traces of carbon monoxide, chlorine, vinyl chloride and cadmium. Constant exposure to these can effect the heart and the nervous system because of their highly toxic nature.

There are two kinds of wires available in the market. The PVC coated ones are more harmful, because they cause chlorine pollution, rated as the most hazardous by the Environment Protection Authority of the US. According to a study by Vatavaran, an NGO, while PVC is being phased out worldwide, in India, the consumption of PVC is rising by 28 per cent every year. The reason: Caustic soda is an established industry in the country and chlorine is a cheap by-product, which is used to manufacture PVC.

The rag-pickers polluting the air around Vasant Kunj are mainly from Bangladesh. When asked how much they earn after burning these wires, they said that they extract five to 10 kgs of copper every day and sell it in Sadar Bazaar for Rs 10 per kg. What is more lethal is copper which is burnt along with the coating, releasing deadlier compounds like copper chloride into the air.

Other areas where rag-pickers regularly burn PVC wires are Jehangirpuri and Kalampuri.