Second-hand smoke and lung cancer

While active smoking has been shown to be the
main preventable cause of lung cancer, second-
hand smoke contains the same carcinogens that are
inhaled by smokers [30]. Consequently, there has
been a concern since release of the 1986 US Sur-
geon General’s report [31] concluding that second-
hand smoke causes cancer among nonsmokers and
smokers. Although estimates vary by exposure lo-
cation (e.g., workplace, car, home), the 2000 Na-
tional Household Interview Survey estimates that a
quarter of the US population is exposed to second-
hand smoke [32]. Second-hand smoke is the third
leading cause of preventable deaths in the United
States [33], and it has been estimated that expo-
sure to second-hand smoke kills more than 3000
adult nonsmokers from lung cancer [34]. Accord-
ing to Glantz and colleagues, for every eight smok-
ers who die froma smoking-attributable illness, one
additional nonsmoker dies because of second-hand
smoke exposure [35].
Since 1986, numerous additional studies have
been conducted and summarized in the 2006 US
Surgeon General’s report on “The Health Conse-
quences of Involuntary Exposure of Tobacco Smoke.” The
report’s conclusions based on this additional ev-
idence are consistent with the previous reports:
exposure to second-hand smoke increases risk of
lung cancer. More than 50 epidemiologic stud-
ies of nonsmokers’ cigarette smoke exposure at
the household and/or in the workplace showed
an increased risk of lung cancer associated with
second-hand smoke exposure [34]. This means that
20 years after second-hand smoke was first es-
tablished as a cause of lung cancer in lifetime
nonsmokers, the evidence supporting smoking ces-
sation and reduction of second-hand smoke expo-
sure continues to mount. Eliminating second-hand
smoke exposure at home, in the workplaces, and
other public places appears to be essential for re-
ducing the risk of lung cancer development among
nonsmokers.