In a far-reaching decision, the Centre has allowed mixing of five per cent ethanol in petrol, use by the automobile sector, in place of methyl tertiary butyl ether (MTBE) to check pollution. The use of ethanol (up to five per cent) in petrol will lead to better combustion and significantly lower emission of pollutants, the Petroleum and Natural Gas minister, Ram Naik said in a suo motu statement in the Lok Sabha today.