Study: Pollution May Cause Asthma
Illness Affects 9 Million U.S. Children
By William Booth
Washington Post Staff Writer
Friday, February 1, 2002; Page A02
LOS ANGELES, Jan. 31 -- For the first time, researchers have
shown that children who breathe heavily polluted air are much more likely to
develop asthma, according to a decade-long study released today.
The scientists said the study is the strongest evidence yet
that smog can not only aggravate existing childhood asthma,
which has reached epidemic proportions among American
youth, but may actually
be one cause of the life-threatening disease.
Asthma is now the leading serious chronic illness
among youth, afflicting about 9 million children,
and it causes not only suffering, but
millions of lost hours at school and at
work for parents who must nurse sick kids.
Asthma sufferers feel their lungs constrict and experience,
during their episodes, each new breath as if drawn through
a narrow straw.
"We've known for some time that smog can trigger attacks
in asthmatics. This study has shown that ozone can cause
asthma as well," said Alan Lloyd, chairman of the California
Environmental Protection Agency's Air Resources Board,
which sponsored the newly published
research conducted by the University of
Southern California. The study is being published in
the current issue of the Lancet, a British
medical journal.
The new findings could invigorate the debate
in Washington over how quickly -- and how cleanly -- America's air
should be scrubbed of pollutants such as ozone, nitrogen oxides
and tiny particulate dust, all produced by the machinery of
the modern world, from automobiles to
power plants to backyard barbecues.
The Bush administration is reviewing standards
for emissions from refineries and factories and other sources,
and the White House and Congress are both being heavily
lobbied by industries and environmentalists.
Because of decades of stricter state and federal regulation,
the air in the United States has steadily become cleaner, but
in many cities, on many days, the government and health officials
still consider the smog levels capable of making people sick.
Researchers said today that their finding that active children
can develop asthma applies not only to the Los Angeles region, but to other
heavily polluted areas, such as Washington, Houston and Las Vegas.
During a news conference announcing the study results,
California officials and the researchers agreed their study suggested
that even as the air has gotten cleaner, "it has not sufficiently
protected children's health," Lloyd said. "We still have a long
way to go."
The study compared new asthma cases in 3,535 children who
were followed over five years in 12 Southern California communities, though
the youths are part of a longer 10-year study. Six of the communities
enjoyed relatively clean skies and six experienced some of the dirtiest
air in the nation.
The researchers further focused their study on children who
participated in active sports, which would require them to draw up to 17 times
the "normal" amount of air sucked into the lungs of a child who was relatively inactive.
The researchers followed children who played active sports
such as soccer, basketball, baseball, tennis and swimming, for at least five years,
starting at age 9. They found that 265 of the children were
diagnosed with asthma during the study, and that those most likely to develop
the disease were exercising in the most polluted cities.
"This research suggests that contrary to conventional wisdom,
ozone is involved in the causation of asthma," said Rob McConnell, associate
professor of preventative medicine at the University of Southern California.
McConnell and his colleagues said they attempted to sort
out other risk factors for asthma, such as a family's income,
smoking habits, pest infestations and histories
of allergies and other ailments.
"Somewhat to our surprise, in low-ozone communities,
we found no increased risk of asthma in children who played team
sports," McConnell said.
What they found was that the children who played the most
active sports in the most polluted areas developed the most asthma.
"The bottom line is this: Exercise is really healthy
for children, for many reasons, and children should be
encouraged to play team sports,"
McConnell said. "But on days when air pollution levels
are expected to be high, children should limit
prolonged outdoor exertion."
The researchers suggested that parents in areas where
the air is dirty monitor the air pollution forecasts and levels,
and take appropriate action, such as stopping exercise and play.
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