SHEIKHUPURA - The newly constructed Sam Nullah serving areas from Kot Abdulmalik to Khanpur Sheikhupura has been filled by the factories, wasted chemical and water and it is feared it could become a breeding ground for dengue larva. The Public Health Department constructed the nullah for drain of industrial treatment plant water for both the side of the industries but the industries threw chemical-mixed water into the nullah. The area people complained the local Environment Department did not take any action against the factories. They demanded the high-up's to take a strict action against the factory owners who illegally release their chemical waste into Nullah.