Exposure to second hand smoking, which leads to various health problems, may be reduced by banning public smoking, a new study has found. Researchers reviewed about 2,500 adult non-smokers' self-reported rates of tobacco smoke exposure in several public and private settings after two smoking bans in Spain. The survey by Catalan Institute of Oncology in Spain showed significantly lower exposure following the second legislation, with participants reporting their overall exposure falling from 72 per cent during the first ban in 2006 to 45 per cent during the second ban in 2011. Exposure decreased across all locations surveyed, beyond the workplaces and hospitality settings covered by the 2011 legislation. Exposure also decreased in residences from 29 per cent to 13 per cent and in transportation spaces from 41 per cent to 13 per cent, researchers said. "The study findings highlight the impact of smoke-free policies, which contradict the hypothesis driven by the tobacco industry that smoke-free legislation merely displace smoking from public to private places," said Esteve Fernandez of the Catalan Institute of Oncology. Also Watch: "Exposure to secondhand smoke in selected outdoor settings may be further reduced by extending smoke-free legislation," said Maria J Lopez of the Public Health Agency in Spain. The study was published in the journal Nicotine and Tobacco Research.