The use of unleaded fuel in vehicles without catalytic convertors defeats the very purpose of the 'green fuel' and will not help cut down on air pollution. At present, a majority of vehicles in the city are not fitted with catalytic convertors but are using unleaded fuel.According to an Environment protection Control Authority brochure, "The use of catalytic convertors was made mandatory for new cars to reduce carbon monoxide and hydrocarbons levels". Unleaded fuel can be equally harmful as the leaded one in the absence of a convertor. A by-product of this 'green' fuel is benzene, which depletes the Ozone layer apart from being carcinogenic.