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#134 - Fine Particles -- Part 3 Federal Standards Allow Disease, 19-Jun-1989

Particles in the air (smoke, dust, soot, haze) are more dangerous to
humans as the size of the particles decreases. Particles are produced
by the combustion of fossil fuels (especially coal, but also oil and
gasoline), and by burning garbage or hazardous waste. In July, 1987,
the U.S. Environmental Protection Agency (EPA) officially recognized
that small particles are more dangerous than larger particles when the
agency established air quality standards for particles smaller than 10
micrometers in diameter. A micrometer is a millionth of a meter and a
meter is about 39 inches.

Now, just two years later, an extensive medical study has shown that
human illness can result from particles in the air at levels that fall
within EPA guidelines. In other words, an area may meet the federal
requirements and yet still make residents sick.

The EPA standard is called PM-10, meaning it is an air quality standard
for "Particulate Matter" 10 micrometers or less in diameter. (See
FEDERAL REGISTER July 1, 1987, pgs. 24634-24669.) The older standard
was for total suspended particulate [TSP] and it did not take into
account the size of particles. The new standard specifically recognizes
that particles smaller than 10 micrometers in diameter are not filtered
out by the nose and throat and can pass into the large airways below
the trachea. The smallest particles, which are less than 2.5
micrometers in diameter, are known as fine particles and they are the
most dangerous because they pass all the way to the bottom of the lungs
where they can move directly into the blood stream. (See RHWN #131
[revised] and RHWN #132.] The federal air quality standard does not
distinguish fine particles from others, though the existence of the PM-
10 standard is recognition that small particles are more dangerous than
large ones.

The federal standard says that, averaged over a year's time, an area's
air should not contain more than 50 micrograms of PM-10 particles in
each cubic meter of air; the 24-hour average is not supposed to exceed
150 micrograms per cubic meter of air. A microgram is a millionth of a
gram and there are 28 grams in an ounce.

For the past decade, researchers at Harvard University have been
studying the relationship of human health to particles in air; their
work has been supported by the federal Department of Energy (DOE) which
plans to burn coal on a massive scale (since nuclear power is,
deservedly, on the ropes).

The Harvard researchers have issued periodic reports on their work; the
most recent one appeared in March, 1989. This study examined 8131 grade
school students in six U.S. cities during the period 197479, and
examined the same students again in 1981-82. To avoid complexities of
age and race, only 5422 white students aged 10 to 12 were the final
subjects of study. The cities were Steubenville, Ohio; St. Louis,
Missouri; Kingston, Tennessee; Portage, Wisconsin; Topeka, Kansas; and
Watertown, Massachusetts.

The students were asked about bronchitis, persistent cough, chest
illness, wheeze and asthma. Bronchitis required a doctor's diagnosis
within the last year; chronic cough was defined as being present for
three months during the past year; chest illness required restriction
of activity for 3 days or more; wheeze was defined as wheeze apart from
colds or for most days and nights during the past year; asthma required
the reporting of a doctor's diagnosis. The Harvard researchers also
asked about three symptoms they didn't expect to be related to air
pollution: earache, hay fever, and nonrespiratory illness or trauma
that restricted activities for 3 days or more.

The Harvard researchers did not collect data specifically on particules
below 10 micrometers in diameter; they collected data (starting in
1978) on PM-15 (particulate matter less than 15 micrometers in
diameter). The annual average PM-15 readings were as follows:

The least polluted city was Portage, WI (10 micrograms, or ug); then
came Watertown, MA (26 ug), Topeka, KS (33 ug), St. Louis, MO (38 ug),
Kingston, TN (42 ug), and finally Steubenville, OH (59 ug), the most
polluted. Boys and girls in the more polluted cities were twice as
likely to have bronchitis, compared with youngsters in the less
polluted cities. Similar results were apparent for chronic cough and
chest illnesses.

These results are important because in the most polluted city
(Steubenville) the annual average particle count was 59 micrograms per
cubic meter and this was a PM-15 measurement; if only particles 10
micrometers or smaller had been counted, the readings would have been
substantially lower. In every other city in the study, the measured
[PM-15] pollution levels were below the allowable federal PM-10
standard, yet children in those cities reported excessive disease
rates. "We found health effects occurring at levels below the current
annual average PM-10 standard," of 50 micrograms per cubic meter, says
Douglas Dockery, leader of the Harvard study. This study provides
unmistakable evidence that the federal standard for particles is
inadequate to protect public health and safety.

The Harvard researchers say their results are important for another
reason: there is some evidence that chest ailments during childhood
predispose a person to permanent, serious breathing problems, like
emphysema, in later life.

The study revealed that the 571 students (10.5% of the total) with
asthma or persistent wheeze were particularly susceptible to
bronchitis. Bronchitis was reported among 25.5% of the children with
asthma or wheeze versus 4.0% of those without; for chronic cough the
rates were 29.5% versus 3.2% and for chest illness 36.5% versus 7.6%.

When compared separately, those children without asthma or wheeze in
the most polluted city were 2.2 times as likely to have bronchitis as
non-asthmatics in the least polluted city; those children with asthma
or wheeze in the most polluted city were 3.8 times as likely to have
bronchitis, compared to asthmatics in the least polluted city.

An important point of this study is that it confirms that the
relationship between particles in the air and childhood disease is
"linear," which means that the more particles in the air, the more
disease there is. This means that ANY increase in particles in the air
is likely to cause disease in someone, somewhere. Thus, an incinerator
proposing to spew particles into the air is very likely doing so at the
expense of some innocent bystander somewhere. The defense, "I'm meeting
all applicable state and federal standards" isn't sufficient to prevent
illness. Even when a polluter meets those standards, someone will most
likely get sick. Who gave polluters the right to make us sick? We, the
people, didn't. It must have been someone else. Let's find out who and
go after them.

Get: Douglas W. Dockery and others, "Effects of Inhalable Particles on
Respiratory Health of Children." AMERICAN REVIEW OF RESPIRATORY
DISEASE, Vol. 139 (March, 1989), pgs. 587-594. For a free reprint,
write: Dr. D.W. Dockery, Department of Environmental Science and
Physiology, Harvard School of Public Health, 665 Huntington Ave.,
Boston, MA 02115.

--Peter Montague


Descriptor terms: epa; pm10; children; regulations; health effects; air
pollution; air quality standards; asthma; lung disease; particulates;