New Delhi, March 25: India’s ban on smoking in public and workplaces seems to be prompting tobacco users to refrain from lighting up even at home, a study that analysed patterns across different states suggests.

The study has revealed a strong association between smoke-free workplaces and smoke-free homes, showing that states where the ban has been rigorously implemented tend to have fewer homes with second-hand smoke.

States with high levels of second-hand smoke at workplaces also had high levels of second-hand smoke in homes, and the states with low levels at work also had low levels at home. (See chart)

“This may be the first signal from India that the ban on public smoking has a spill-over effect at home,” said Christopher Millet, a public health researcher at Imperial College, London, and a member of the study team.

“The ban may be changing social norms,” Millet told The Telegraph. “People seem to be saying to themselves — if we can’t expose our colleagues to second-hand smoke, why should we expose our families?”

The findings, published this week in the journal Tobacco Control, are in line with similar observations from the US and the UK where governments had prohibited smoking in public places.

India had implemented a national legislation to prohibit smoking in public places and workplaces in October 2008. A modest fine of Rs 200 is imposed for violations of the law. But the rigour of implementation varies across states.

The research by Millet and his colleagues from Imperial College, the University of California, San Francisco, and the Public Health Foundation of India, New Delhi, measured second-hand smoke through 12,561 people who worked indoors outside homes.

The study found that people who reported their workplaces as smoke-free were more likely to be living in smoke-free homes and people living in urban areas were more likely to be living in smoke-free homes than those in rural areas.

Public health specialists say a decline in smoking at home is likely to reduce second-hand smoke exposure to children. This, in turn, is expected to translate into a reduced risk of asthma for children, Millet said.

The study drew on data from the Global Adult Tobacco Survey, which had revealed that India has about 110 million smokers. The results support the arguments that restrictions on smoking in public reduces the acceptability of exposing people to second-hand smoke even at home.

“These findings highlight the effectiveness of smokefree legislation in India,” Monika Arora, director of health promotion and tobacco control at the Public Health Foundation of India, who was not associated with the study, said in a media release issued by the foundation.