Ethanol-powered cars have been touted as a potential saviour of the global climate, but a new report by Stanford University in California has warned that they could have worse effects on human health than those running on regular petrol. Scientists at Stanford set up a computer model to simulate two environments in 2020 - one in which petrol has been relied up as the fuel of choice for motorsts, and one where vehicles were fuelled by E85, a mixture of 85 per cent ethanol and 15 per cent petrol. They discovered that the air quality in the ethanol-dominated scenario had significantly more ozone than the petrol-dominated one, which would provoke serious respiratory problems and asthma attacks in some people. In Los Angeles alone, this would translate to an extra 120 deaths per year, the study claims.It also showed that, although two atmospheric carcinogens actually reduced in the ethanol test atmosphere, overall levels of associated cancers actually increased. In light of this research, Stanford University's Mark Jacobsen said, "if we're not getting any health benefits, then why continue to promote ethanol?" Meanwhile, the EU wants biofuels to power 10 per cent of all transportation by 2010.