Environmental Engineering Reference
In-Depth Information
noxious substances is well recognized by nonsmokers when they enter
a room where smoking has occurred. Those who come into contact
with the smoker's residues receive chronic exposure to the chemicals
and carcinogens left after the smoke has dissipated.
The harm to children from cigarettes starts before birth. Numerous
studies have shown that women who smoke have a harder time getting
pregnant and a greater risk of spontaneous abortion and having low-
birth-weight babies. Children of mothers who smoke grow up to score
10 percent lower on standardized tests than other children.
31
This sug-
gests that more than 33 million children are at risk of mental defi cits
from second-hand smoke. In addition, second-hand smoke is implicated
in sudden infant death syndrome, respiratory problems, ear infections,
and asthma attacks.
Radon Gas
Radon is a colorless, tasteless, odorless, radioactive gas produced by the
natural disintegration of uranium in rocks and soils. It originates out-
doors and is heavily diluted by the circulating air, and so poses no threat
to those outdoors.
Inside houses in confi ned and poorly ventilated areas such as base-
ments, radon may become concentrated, and long-continued exposure
to it may be dangerous. But few people live in basements in houses built
on uranium-bearing rock or soil where cracked fl oors may be allowing
radon to accumulate to dangerous amounts. And the average American
moves ten to eleven times during a lifetime and so is unlikely to be
exposed to high accumulations of radon for a signifi cant length of time.
Radon is a danger to only a trivial number of people.
Asbestos
Two diseases are associated with the inhalation of large amounts
of asbestos: asbestosis and mesothelioma. Deaths from both are
directly linked to long-term occupational exposure to asbestos in the
preregulated workplace.
Asbestosis is a chronic lung disease caused by large amounts of asbes-
tos that have been deposited in the lungs through inhalation. It causes
scarring of the lung and decreased lung effi ciency, putting stress on the
heart, and it can result in heart failure. It is rare for asbestosis to develop
in anyone who has not been exposed to large amounts of asbestos on a
regular basis for at least ten years. Symptoms of the disease do not
usually appear until fi fteen to twenty years after initial exposure to
