http://story.news.yahoo.com/news?tmpl=story&u=/usatoday/20031016/ts_usatoday/11904970
Thu, Oct 16, 2003
Smoggy skies persist despite decade of
work
By Traci Watson, USA
TODAY
The amount of smog
over the USA failed to decline during the
past decade despite a nationwide effort to improve air quality,
statistics from the Environmental Protection Agency show.
Smog levels dropped
during the 1980s. But the latest edition of
the EPA's annual report on air quality shows that smog levels
didn't
get better from 1993 through 2002. Independent scientists have
drawn
similar conclusions.
"It's a bit of
a black eye for EPA," says Daniel Jacob, a Harvard
University chemist who studies smog. "We were making progress
in the '80s, and the progress has halted."
One likely reason why
the smog isn't lifting: Americans are
driving more miles than they did in the 1980s. And they're
driving vehicles that give off more pollution than the cars
they drove in the '80s.
But the numbers also
suggest that reducing smog has proved
slower and more difficult than the EPA realized. Smog
"is probably our single biggest concern in terms of air
quality right now," acting EPA chief Marianne Horinko says.
Environmentalists fear
that recent changes to power plant
rules will make eliminating smog even harder. In August,
the EPA loosened rules requiring power plants to add
pollution-control equipment when the plants expand.
The National Academy of Sciences will soon start studying
how the change will affect pollution levels.
Smog, also known as
ozone, often appears as a grayish-white haze.
It forms when sunlight mixes with nitrogen oxides and volatile
organic compounds.
Nitrogen oxides are
gases emitted by power plants, factories
and vehicles. Volatile organic compounds are vapors given off
by gasoline, paint and other substances
A layer of ozone in
the upper atmosphere helps protect humans
from the sun's radiation. But ozone near the ground smog causes
lung inflammation and triggers asthma attacks.
During the 1980s, the
EPA focused on cutting emissions
of the organic compounds. That lowered smog levels at
the time. But now, vapor levels have been cut so low
that reducing them further won't help, scientists say.
That has the EPA focusing
on cutting nitrogen oxides,
a method that scientists say reducessmog slowly and
inefficiently.
Power plants began
cutting emissions of nitrogen oxides
in 1996. Those cuts, coupled with cleaner cars, caused
nitrogen oxide emissions to drop 12% from 1993 to 2002.
Yet smog levels remained the same. That's because big cuts
in nitrogen oxides are needed to make a dent in smog levels.
"We're not enthused
about the way it has gone," acknowledges
Jeff Clark, the EPA's director of policy analysis for air quality.
America's love of driving
helps explain why levels remain high.
Vehicles contribute to smog by emitting nitrogen oxides from
their tailpipes. In 2002, cars and trucks traveled roughly
50% more miles than in 1993.
And during 2001 and
2002, Americans bought more light trucks
pickups, minivans and sport-utility vehicles than cars.
EPA rules permit light trucks to emit more nitrogen oxides
than cars are allowed to give off.
During the next few
years, new regulations are likely to help
reduce smog in some parts of the country. Those rules will
force 22 states and the District of Columbia to lower their
emissions of nitrogen oxides.
The EPA also is requiring
new cars and light trucks to emit
fewer nitrogen oxides. To comply with the rules, companies
will have to spend more than $15 billion to install new
technologies to control pollution and to retool manufacturing
lines.
Even so, smog levels
are expected to remain above EPA limits
in some areas, despite the new requirements. That's because
smog levels are so high in those areas now. It was easy to
take the first steps to clean up smog, says the EPA's Clark.
But reducing smog enough to make the air in those areas safe
to breathe "is going to be a lot more difficult."
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