Download Secondhand Smoke

Secondhand Smoke
• Secondhand smoke (SHS) is a mixture of
2 forms of smoke that come from burning
tobacco:
• Sidestream smoke – smoke from the
lighted end of a cigarette, pipe, or cigar
• Mainstream smoke – the smoke exhaled
by a smoker
• Sidestream smoke has higher
concentrations of cancer-causing agents
(carcinogens) than mainstream smoke.
And, it has smaller particles than
mainstream smoke, which make their way
into the lungs and the body’s cells more
easily.
Why is secondhand smoke a
problem?
• Secondhand smoke is classified as a
“known human carcinogen” (cancercausing agent) by the US Environmental
Protection Agency (EPA), the US National
Toxicology Program, and the International
Agency for Research on Cancer (IARC), a
branch of the World Health Organization.
Secondhand smoke causes
cancer
• Tobacco smoke contains more than 7,000
chemical compounds. More than 250 of
these chemicals are known to be harmful,
and at least 69 are known to cause cancer.
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• IARC reported in 2009 that parents who
smoked before and during pregnancy
were more likely to have a child with
hepatoblastoma. This rare cancer is
thought to start while the child is still in the
uterus. Compared with non-smoking
parents, the risk was about twice as high if
only one parent smoked, but nearly 5
times higher when both parents smoked.
breast cancer
• Both mainstream and SHS have about 20
chemicals that, in high concentrations,
cause breast cancer in rodents. And we
know that in humans, chemicals from
tobacco smoke reach breast tissue and
are found in breast milk.
• One reason the link between SHS and
breast cancer risk in human studies is
uncertain is because breast cancer risk
has not been shown to be increased in
active smokers. One possible explanation
for this is that tobacco smoke might have
different effects on breast cancer risk in
smokers and in those who are exposed to
SHS.
Findings on smoking, secondhand
smoke, and health
• SHS kills children and adults who don’t
smoke.
• SHS causes disease in children and in
adults who don’t smoke.
• Exposure to SHS while pregnant
increases the chance that a woman will
have a spontaneous abortion, stillborn
birth, low birth-weight baby, and other
pregnancy and delivery problems.
• Babies and children exposed to SHS are
at an increased risk of sudden infant death
syndrome (SIDS), acute respiratory
infections, ear infections, and more severe
and frequent asthma attacks.
• Smoking by parents can cause wheezing,
coughing, bronchitis, and pneumonia, and
slow lung growth in their children.
• SHS immediately affects the heart, blood
vessels, and blood circulation in a harmful
way. Over time it can cause heart disease,
strokes, and heart attacks.
• SHS causes lung cancer in people who
have never smoked. Even brief exposure
can damage cells in ways that set the
cancer process in motion.
• Chemicals in tobacco smoke damage
sperm which might reduce fertility and
harm fetal development. SHS is known to
damage sperm in animals, but more
studies are needed to find out its effects in
humans.
• There is no safe level of exposure to SHS.
Any exposure is harmful.
• Many millions of Americans, both children
and adults, are still exposed to SHS in
their homes and workplaces despite a
great deal of progress in tobacco control.
• On average, children are exposed to more
SHS than non-smoking adults.
• The only way to fully protect non-smokers
from exposure to SHS indoors is to
prevent all smoking in that indoor space or
building. Separating smokers from nonsmokers, cleaning the air, and ventilating
buildings cannot keep non-smokers from
being exposed to SHS.