The tiny killers

-- (Credit: Vishwajyoti)A TINY speck of particle floating in the air
could ultimately send you to the grave.
That air pollution leads to respiratory
and heart ailments speeding up death, is
a well known fact. But a recent study by
an environmental group has revealed
alarming facts about the lethal powers
of seemingly innocuous fine particles of
air pollution. According to the survey of
239 cities by the Natural Resources
Defense Council (NRDC) in the us, tiny
particles of airborne pollution cause
64,000 deaths nationwide every year.

The mortality rate due to particle
pollution is the highest among people
who already have breathing problems,
including asthmatic children and some
elderly people. According to the NRDC,
coal-fired power plants are the largest
source of 'fine particle pollution' in the
us. The other culprits contributing to the
pollution are diesel-burning trucks and
buses, petrol-powered cars, industrial
boilers and even wood-burning stoves.

In a country which takes pride in
being in the forefront of environmental
legislation, the study has thrown open a
floodgate of debate on the laws which
govern air pollution. The Clean Air
Act of 1970, which was strengthened
in 1977, considerably improved the
quality of America's air. Cleaner cars
and cleaner fuels have been produced in
accordance with tough federal mandates. Still, it is now obvious, the war
against air pollution is far from over.
More than 5,000 lives in Los Angeles
could be saved annually if more stringent regulations to curb small-particle
pollution were enforced.

The existing laws have loopholes
that let the finer particles to pass
through. Pollution control laws like the
Clean Air Act were essentially drafted to
reduce the amount of all airborne
microscopic particles that are 2.5 to 10
microns in diameter. (A human hair
measures 100 microns in diameter.)
Recent discoveries have shown that particles smaller than 2.5 microns in diameter pose the greatest health risk.
These minute particles, when inhaled,
are drawn deep into the lungs. They
escape the body's natural defences and
settle in the most fragile sections of the
lungs, leading to serious respiratory
ailments and even cancer.

An overhauling of the regulatory
standard a standard that permits 50
micrograms of particulates per cu m of
air does not cover the particles that have
the most damaging effect on health -
devised by the Environmental
Protection Agency (EPA) to enforce the
air pollution law has been proposed.
NRDC said that a federal rule narrowing
down the limit of particulates to 20
micrograms per cu m of air (in measurements averaged over a year) would
save about 4,700 lives a year in the us,
while a limit of 10 micrograms per cu m
would save about 56,000 lives a year.

The new environmental legislation
has been on the anvil for some time
now. The EPA has been considering
whether to issue new standards that
would be strong enough to shield the
public against these microscopic killers.
Carol Browner, administrator of the
EPA, had taken note of epidemiological
studies, including a survey by the
American Cancer Society conducted
earlier. The recent study by NRI)c adds
to the necessity of enacting new legislation as soon as possible. Said Browner,
"This is a very serious issue, and we are
moving ahead quickly to come up with
conclusions. The science suggests that
the smaller particles really are a problem". The EPA is likely to propose a new
rule concerning small-particle pollution
by November this year. It is expected to
be ready for enactment next year.

However, tightening the noose of
regulations alone will not deliver cleaner air. When new rules come into
force, the us science and industry will
have to come up with better alternatives
to meet it. But grumblings can already
be heard from industries that may have
to make investments in new technologies for pollution control. For example,
lithe American Mining Association dismissed the study saying that it was based
Jon "junk science".

Before enforcing costly new regulations, the EPA will have to make sure that
they are backed by solid scientific evidence. Studies identifying the small particles as deadlier than bigger ones are
relatively new and small in number. But
then, the industry always puts up a
defensive front when confronted with
environmental responsibilities. Hopefully, the industry's stand will not deter
the EPA from coming up with the right
regulatory weapon to fight the tiny
killers.

While scientists may take some time
to find an answer to fine-particle pollution, the solution to the problem of airborne soil particles could be at hand. The
source of these particles had long
remained unknown. But Ann Kennedy, a
soil scientist with the us Agricultural
Research Service in Washington, claims
that she can identify the source of dust by
examining the fatty acid content of the
microorganisms clinging to the particles.
According to John Bachmann, an EPA
official, fatty acid profiling could play a
crucial role in curbing air pollution.