Tobacco smoke, the main indoor air pollutant

Indoor air quality is generally worse than outdoor air quality. Of the eight major indoor air pollutants, tobacco smoke is a component of 5 chemical pollutants. Environmental tobacco smoke (ETS) is the most dangerous indoor air pollution.^[1].

A set of cross-sectional data collected in 2006 from a sample of households in 31 countries (12 in Asia, 9 in the Americas, 3 in the Middle East, 7 in Europe) show that the concentration of nicotine in the air are:

• 17 times higher in homes where a smoker is present - compared to a non-smoking home;
• 12.9 times higher in homes where smoking is allowed indoors;
• Nicotine concentrations found in the hair of women and children increase with the number of smokers in the household^[2].

Even when opening windows, the components of smoke remain in the air. They are also partly absorbed by curtains, fabrics, carpets and their emission continues over time (link to article on third-party smoking).

The European Environment Agency reminds that "poor indoor air quality can be harmful"^[3] and this is particularly true for vulnerable groups and children. The consequences of exposure can be immediate in the case of acute exposure with a high concentration level or affect the individual in the long term in the case of chronic exposure.

In a context where many countries have regulated smoking in public places and where there is a real trend towards extending smoking bans in these places, passive smoking in private places remains common.^[4]WHO recalls that passive smoking remains a major problem^[5].