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#74 - New Air Pollution From Landfills: Asbestos And Fiberglass Hazards, 24-Apr-1988

A new danger from municipal landfills is emerging from scientific
studies: cancer causing air pollution from asbestos, fiberglass and
other synthetic mineral fibers. The problem has two parts: the health
danger from the fibers, and the release of fibers from landfills.

Everyone agrees that asbestos causes cancer in humans. An estimated
9,000 Americans now die prematurely each year from asbestos exposure
and the number increases yearly. The federal government and many states
now sponsor programs to remove asbestos from schools and public
buildings. But where does the asbestos go after removal? It goes either
into a hazardous waste landfill, or it goes into a municipal landfill,
the town dump. In both cases, the effect is the same: the asbestos goes
into the ground, not far below the surface.

As the dangers from asbestos have been recognized, it has been phased
out in favor of fiberglass and so-called "mineral wool" (though
fiberglass is much more popular than mineral wool). Such synthetic
fibers are now used in more than 50,000 different consumer products--
building materials and insulation, cars, furniture, packaging,
draperies, and many other products.

Industry spokespeople insist that these fibers are 100% safe, but
studies have been appearing in the scientific literature for at least
19 years indicating that some synthetic fibers cause cancer and other
diseases in laboratory animals. While searching for the mechanism by
which asbestos causes cancer, scientists in the late 1960s discovered
that the size of the fiber (and not its chemical composition) is the
key to the carcinogenicity of fibers. In a series of papers published
from 1969 to 1977, Dr. Mearl F. Stanton of the National Cancer
Institute (Bethesda, MD) reported that glass fibers less then 3 microns
in diameter and greater than 20 microns in length are "potent
carcinogens" in rats; and, he said in 1974, "it is unlikely that
different mechanisms are operative in man." A micron is a millionth of
a meter (and a meter is about three feet). Since that time, studies
have been appearing in the literature, showing that fibers of this size
not only cause cancer in laboratory animals, but also cause changes in
the activity and chemical composition of cells, leading to changes in
the genetic structure and in the cellular immune system. Although these
cell changes may be more common (and possibly more important) than
cancer, it is the cancer-causing aspects of synthetic fibers that have
received most attention.

The cancer alert hit the front page of the NEW YORK TIMES March 15,
1987: "Emerging evidence that fiberglass and other manufactured mineral
fibers may cause lung cancer and other diseases is creating a
sensitive, potentially farreaching public health issue." The TIMES went
on to discuss several recent scientific studies showing that excessive
lung cancer can be observed among workers exposed to mineral fibers on
the job. At a meeting of the World Health Organization in Copenhagen in
October, 1986, three studies of worker health reported significant
increases in lung cancer among workers exposed to mineral fibers. Dr.
Philip Enterline, professor of biostatistics at Pittsburgh University's
School of Public Health, told the NEW YORK TIMES that the data he
presented at Copenhagen were "surprising," given the low levels of
exposure among the workers he studied. "It may yet turn out that these
fibers have to be controlled the way asbestos is controlled," he said.

The federal EPA (U.S. Environmental Protection Agency) seems dimly
aware that this problem is a sleeping giant. Dr. David L. Dull, acting
director of the chemical control division of the EPA told the TIMES,
"Some evidence suggests we ought to treat it as a serious problem and
regulate it like asbestos." Dr. Dull also told the TIMES, "If I had a
choice of being exposed to asbestos at current exposure levels and to
respirable manmade fibers, I would breathe asbestos every time because
the exposure limits are so much more stringent."

The U.S. now consumes more than a billion pounds of synthetic mineral
fibers each year--approximately the same as our consumption of asbestos
was during peak years of use (the '70s). The vast majority of synthetic
fibers are not small enough to fall within the dangerous size-range--
only a small fraction of the total mass of fiberglass, for example,
consists of fibers thinner than 3 microns and longer than 20 microns.
Nevertheless, a small fraction of a billion pounds represents a
tremendous quantity of tiny, dangerous fibers dumped into the
environment year after year. And consumption increases each year as
these fibers replace asbestos. Furthermore, industry is constantly
striving to make glass fibers smaller and smaller because the smallest
fibers are most useful (they have the best insulating properties, for
example). Three scientific researchers in 1970 summed up the outlook
for fiberglass: "Recent advances in reducing the diameter of the fibers
and the development of new coating materials will aid in the
development of countless new products. The fibrous glass manufacturers
believe that most homes will be constructed out of or decorated with
some material made of fiberglass." Today, eighteen years later, this
prediction has come true. Synthetic fibers are a $3 billion-a-year

So far as we know, regulatory officials have never asked where asbestos
and fiberglass go after they are dumped into a landfill. However, back
in the early '70s, the National Insulation Manufacturers Association
hired three scientists to evaluate contamination of the general
environment by fiberglass. Their papers were never published, but were
made available to us by one of the researchers himself.

The three researchers began by finding glass fibers in the air inside
public buildings and they wanted to find the source. They discovered it
was outdoor air that contains the fibers. They then began looking at
outdoor pollution. They found that they could measure glass fibers in
the air on a remote, rural mountain top in California. Where was it
coming from?

"A point source of airborne glass and other fibers was found to be a
disposal site (landfill of San Francisco Bay) where industrial waste
containing fibrous materials had been disposed of for many years. A
sample of the dust cloud generated by a moving passenger car driven in
a circle approximately 100 yards in diameter over the compacted surface
of this site gave a concentration of approximately 500 glass fibers
[per] liter.... A sample taken about 100 yards downwind from several
earthmoving and compacting machines at work on the site... showed
concentrations of 300 glass fibers [per] liter....."

Our landfills are enormous repositories of asbestos and synthetic
fibers. It is clear that, as time passes, natural erosion releases some
of this material back into the atmosphere. In less than two
generations, we have contaminated the entire atmosphere of the United
States with glass fibers, even the most remote areas. Encasing fibers
in epoxy-like blocks before disposal should reduce the problem
substantially. An even better solution would be to stop using synthetic
fibers. For the majority of uses, alternative materials already exist.
What seems lacking is the will to switch.

(For citations to the unpublished work, see "Fiber Glass," ENVIRONMENT
MAGAZINE, Sept., 1974, pgs. 6-9.)

--Peter Montague


Descriptor terms: landfilling; asbestos; fiber glass; particulates;
cancer; air pollution; carcinogens; mearl stanton; nci; studies;
findings; lung cancer; occupational safety and health; who; philip
enterline; epa; david dull; man-made mineral fibers; ca;