Scotland's smoking ban is reducing second-hand exposure but is not protecting children at home, three studies suggest.
After a series of questionnaires and saliva tests the studies, published by the BMJ, found that nicotine levels in primary school children have reduced by 39% in non-smoking homes.
There has also been a 49% reduction in nicotine levels of non-smoking adults since the ban was introduced in March.
Despite this, non-smokers living in smoking households continued to have high levels of second-hand exposure.
Researchers from the University of Edinburgh and NHS Health Scotland, who carried out the studies, believe the legislation has had a positive short-term impact but done little to dissuade those who smoke at home.
Findings are being published to coincide with a briefing 'Toward a Smokefree Society' taking place at the Edinburgh International Conference Centre.