Abstract: One of the major goals of developing countries is to build smart cities. One aspect of a smart city is to build efficient and intelligent traffic management system especially the road traffic that avoids congestions, accidents and many kinds of inordinate delays. Many factors are to be considered for effecting smooth traffic management system that includes the consideration of toxic gases surrounding traffic routes, visualization, Imaging, remote sensing, messaging and a cognitive decision making system. The Traffic management also requires a versatile communication system that facilitate communication among heterogeneous devices and systems. Toxic gases in and around the traffic are quite dangerous and effect the traffic in many ways. There should be a composite system that caters to sensing the toxic gases in around the signal post systems and regulate the traffic based on the extent of presence of the Toxic gases. In this study, a composite bio sensing system is presented that senses various kinds of toxic gases and regulate the flow of traffic based on the extent of presence of those gases.