Passive or involuntary smoking occurs when the exhaled and
ambient smoke (otherwise known as environmental or secondhand
smoke) from one person's cigarette is inhaled by other people.
Passive smoking involves inhaling carcinogens, as well as other
toxic components, that are present in secondhand tobacco smoke.
Carcinogens that occur in secondhand tobacco smoke include benzene,
1,3-butadiene, benzo[a]pyrene,
4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone, and many
others.
It is confirmed that, in adults, secondhand smoke causes lung
cancer, nasal sinus cancer, breast cancer in younger women, heart
disease, heart attacks, and asthma induction. Secondhand smoke is
also known to harm children, infants and reproductive health
through acute lower respiratory tract illness, asthma induction and
exacerbation, chronic respiratory symptoms, middle ear infection,
lower birth weight babies, and Sudden Infant Death
Syndrome.[15]
In June 2006, US Surgeon General Richard H. Carmona called the
evidence against passive smoke "indisputable" and said "The science
is clear: secondhand smoke is not a mere annoyance, but a serious
health hazard that causes premature death and disease in children
and non-smoking adults.".[16] Passive smoking is one of the key
issues that have lead to introduction of smoking bans, particularly
in workplaces.
The composition of Environmental tobacco smoke (ETS) is similar to
fossil fuel combustion products that contribute to air pollution,
and has been shown to be responsible for indoor particulate matter
(PM) levels far exceeding official outdoor limits.[17]
