260 Unit 4 Understanding and Avoiding Hazardous Substances
Copyright Goodheart-Willcox Co., Inc.
Tobacco and Your Body
On average, long-term smokers die 13 to 15 years
earlier than nonsmokers. Tobacco use increases a per-
son’s risk for developing a number of major health prob-
lems, including cancers of the mouth, pharynx, esopha-
gus, lung, and bladder. People who smoke also increase
their risk for developing coronary heart disease, stroke,
emphysema, bronchitis, and respiratory infections.
The Surgeon General of the United States recent-
ly issued a report on smoking and health that linked
smoking with numerous additional illnesses. This re-
port showed higher risk factors among smokers for de-
veloping diabetes, colorectal and liver cancers, vision
loss, tuberculosis, and arthritis. People who smoke also
have a higher risk factor for minor health problems.
Tobacco products and smoke contain thousands of
chemicals and toxic substances that harm the body. Nic-
otine, carbon monoxide, tar, and carcinogens are just a
few of the harmful substances present in tobacco prod-
ucts (Figure 9.2). Many health problems result from
damage to the cardiovascular and respiratory systems
caused by the harmful substances in tobacco products.
The Cardiovascular System
The cardiovascular system includes the heart and blood transportation
system in your body. Smokers have a higher risk of developing heart dis-
ease and hypertension (high blood pressure) than nonsmokers. Smokers
are also twice as likely to die from a heart attack as nonsmokers. This is
partly because of the substantial impact that nicotine and carbon monoxide
have on the cardiovascular system.
Nicotine. When people use forms of tobacco, nicotine enters their
bloodstream. Its presence triggers the release of the hormone adrenaline, a
stimulant. Adrenaline triggers an increase in heart rate, breathing rate, and
blood pressure. This increase in speed and pressure of blood fl ow in the
body makes the heart work harder to pump blood faster around the body.
Nicotine also causes the blood vessels to constrict. The heart must work
harder to pump blood through increasingly narrow vessels. Gradually, nicotine
leads to changes in the walls of the blood vessels, which make it easier for fatty
substances such as cholesterol (plaque) to build up in the arteries. This can dis-
rupt the fl ow of blood through the body because the fatty deposits restrict the
ease of blood transportation. Over time, this buildup increases the risk of a heart
attack or stroke, which occur when an artery becomes completely blocked.
Carbon Monoxide. Cigarette smoke contains high levels of carbon
monoxide, a poisonous gas. When inhaled, carbon monoxide interferes
with the ability of blood cells to carry oxygen. This reduces the amount of
oxygen in the blood and the amount of oxygen that reaches the heart.
Figure 9.2 Chemicals Found in Cigarettes
Chemical Other Locations
acetone found in nail polish remover
acetic acid an ingredient in hair dye
ammonia a common household cleaner
arsenic used in rat poison
benzene found in rubber cement
butane used in lighter fl uid
cadmium active component in battery acid
carbon monoxide released in car exhaust fumes
formaldehyde embalming fl uid
hexamine found in barbecue lighter fl uid
lead used in batteries
naphthalene an ingredient in mothballs
methanol a main component in rocket fuel
nicotine used as insecticide
tar material for paving roads
toluene used to manufacture paint
carbon monoxide
a poisonous gas found in
cigarette smoke; negatively
affects cells’ ability to
carry oxygen