Breathing other people's smoke is called passive, involuntary or second‑hand smoking. The non-smoker breathes "side stream" smoke from the burning tip of the cigarette and "mainstream" smoke that has been inhaled and then exhaled by the smoker. Environmental tobacco smoke (ETS) is a major source of indoor air pollution. Tobacco smoke contains over 4000 chemicals, some of which have marked irritant properties and some 60 are known or suspected carcinogens (cancer causing substances). http://www.ash.org.uk/html/passive/html/passive.html
The discovery of the dangers of ‘passive smoking’ in the 1980s marked the third phase of the tobacco wars and a decisive shift in the anti-smoking campaign. The first indication of this problem came in a paper from Japan in 1981; by 1986 the US Surgeon-General noted that some thirteen studies from five different countries had confirmed an increased risk. The resulting 1987 ban on smoking on US domestic air flights and the attendant controversy put the passive smoking issue decisively on the public agenda. In 1988, the Froggat Committee, an independent scientific committee on smoking and health, estimated that passive smoking caused an increased risk of lung cancer of between 10 and 30 per cent and recommended restrictions on smoking in workplaces and in public. The case against passive smoking gathered momentum through the 1990s. In 1992 the US Environmental Protection Agency declared ‘environmental tobacco smoke’ (ETS) a carcinogen, or cancer-causing agent (Al-Delaimy WK, Crane J, Woodward A: 2000).
In 1982 and 1986, the Surgeon General assessed the risk of lung cancer from environmental tobacco smoke (ETS), also called involuntary smoking and passive smoking --the term generally used here.......
