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How We Got Here -- Part 1: The
History of Chlorinated Biphenyls (PCBs)
by Peter Montague, Ph.D.
from Rachel's Hazardous Waste News #327
If you had to pick one chemical that best exemplified our modern situation,
it might well be PCBs (polychlorinated biphenyls).
PCBs were first manufactured commercially in 1929 by the Swan Corporation,
which later became part of Monsanto Chemical Company of St. Louis, Missouri.
[1] Monsanto then licensed others to make PCBs
and the product took off. PCBs conduct heat very well, but do not conduct
electricity, and they do not burn easily. Furthermore, they do not change
chemically--they are stable--and they are not soluble in water. Therefore
they are ideal insulators in big electrical transformers and capacitors
(devices that store electricity). As electricity came into widespread use
during the first half of this century, equipment suppliers like GE and Westinghouse
became major users of PCBs.
Many of the characteristics that make PCBs ideal in industrial applications
create problems in the environment. Like many other chlorinated hydrocarbons,
PCBs are soluble in fat, though not in water, so they tend to accumulate
in living things and to enter food webs, where they concentrate. Larger,
older predators tend to accumulate PCBs in their fatty tissues, including
their eggs (in the case of birds and fish) and their milk (in the case of
mammals). PCBs were first recognized as an environmental problem in 1966
when a Swedish researcher reported finding them in 200 pike from all over
Sweden, in other fish, and in an eagle. [2]
For the next decade, scientists accumulated information about PCBs, finding
them disrupting food webs all over the planet. By 1976, the destruction
wrought by PCBs was so obvious and so well understood that even the U.S.
Congress comprehended the danger and took action, outlawing the manufacture,
sale, and distribution of PCBs except in "totally enclosed" systems.
Between 1929 and 1989, total world production of PCBs (excluding the Soviet
Union) was 3.4 billion pounds, or about 57 million pounds per year. Even
after the U.S. banned PCBs in 1976, world production continued at 36 million
pounds per year from 1980-1984 and 22 million pounds per year, 1984-1989.
The end of PCB production is still not in sight. [3]
The whereabouts of 30 percent of all PCBs (roughly a billion pounds)
remains unknown. Another 30 percent reside in landfills, in storage, or
in the sediments of lakes, rivers, and estuaries. Some 30 percent to 70
percent remain in use. The characteristics of PCBs (their stability and
their solubility in fat) tend to move them into the oceans as time passes.
Nevertheless, it is estimated that only one percent of all PCBs have, so
far, reached the oceans. [3]
The one percent that HAVE reached the oceans are causing major problems.
As noted above, PCBs tend to concentrate in the food chain; the higher you
are on the food chain, the greater the concentration of PCBs. Large fish,
and creatures that eat large fish, tend to accumulate thousands of parts
of million (ppm) in their flesh. Furthermore, by a cruel twist of fate,
large birds and large marine mammals (seals, sea lions, whales, and some
dolphins) lack enzyme systems to efficiently detoxify PCBs. As a result,
PCBs build up in the bodies of oceanic predators and are passed to their
offspring through eggs (in the case of fish and birds) and milk (in the
case of mammals). PCBs mimic hormones and are a powerful disruptor of the
endocrine system that governs reproduction. Marine mammals are already having
trouble reproducing. [4] It is entirely possible
that, as more PCBs reach the oceans, all large mammals will disappear. [5]
Humans, too, are contaminated by PCBs and are passing these powerful
toxins to their infant children through breast milk. In the U.S. and other
industrialized countries, PCBs are present in breast milk at about 1 part
per million (ppm) in the milk fat. An infant drinking milk contaminated
at this level will take in a quantity of PCBs that is 5 times as high as
the recommended "allowable daily intake" for an adult, as established
by the World Health Organization. [6]
Children exposed in the womb to PCBs at levels considered "background
levels" in the U.S. have been found to experience hypotonia (loss of
muscle tone) and hyporeflexia (weakened reflexes) at birth, delays in psychomotor
development at ages 6 and 12 months, and diminished visual recognition memory
at 7 months. [7]
How did we get here?
In 1937--just eight years after Swan Chemical began manufacturing PCBs
in commercial quantities--the Harvard School of Public Health hosted a one-day
meeting on the problem of "systemic effects" of certain chlorinated
hydrocarbons including "chlorinated diphenyl" (an early name for
PCBs). [8] The meeting was attended by representatives
from Monsanto, General Electric, the U.S. Public Health Service, and the
Halowax Corporation, among others.
Before World War I, the Halowax Corporation began manufacturing chlorinated
naphthelenes as a coating for electric wire and companies like General Electric
began using it. The president of Halowax, Sandford Brown, told the meeting
that they had observed no problems in their workers until "the past
4 or 5 years... Then we come to the higher stages [greater number of chlorine
atoms in the mixture], combined with chlorinated diphenyl and other products,
and suddenly this problem is presented to us." [8]
By the mid-1930s, workers at Halowax and at GE, and even some of their customers,
were breaking out with chloracne--small pimples with dark pigmentation of
the exposed area, followed by blackheads and pustules. In 1936 three workers
at the Halowax Company died, and Halowax then hired Harvard University researchers
to expose rats to these chlorinated compounds, to see if they could discover
the underlying cause. The Harvard researchers made "a number of estimates
of chlorinated hydrocarbons in the air of different factories," then
designed experiments to expose rats to similar levels. They reported that
"the chlorinated diphenyl is certainly capable of doing harm in very
low concentrations and is probably the most dangerous [of the chlorinated
hydrocarbons studied]." [8] And, they said,
"These experiments leave no doubt as to the possibility of systemic
effects from the chlorinated naphthalenes and chlorinated diphenyls."
[8]
From a brief report on the one-day conference, we can gather that problems
caused by PCB exposures were serious and widely known. Mr. F.R. Kaimer,
assistant manager of General Electric's Wireworks at York, Pa., said, "It
is only 1 1/2 years ago that we had in the neighborhood of 50 to 60 men
afflicted with various degrees of this acne about which you all know. Eight
or ten of them were very severely afflicted--horrible specimens as far as
their skin conditions was concerned. One man died and the diagnosis may
have attributed his death to halowax vapors, but we are not sure of that...."
[8]
GE's medical director, Dr. B. L. Vosburgh of Schenectady, N.Y., attended
the meeting. He said, "About the time we were having so much trouble
at our York factory some of our customers began complaining. We thought
we were having a hysteria of halowax mania throughout the country."
Monsanto Chemical Company was represented at the meeting by R. Emmett
Kelly. Mr. Kelly told the meeting, "I can't contribute anything to
the laboratory studies, but there has been quite a little human experimentation
in the last several years, especially at our plants where we have been manufacturing
this chlorinated diphenyl." He went on to describe the results of Monsanto's
human experiments: "A more or less extensive series of skin eruptions
which we were never able to attribute as to cause, whether it was impurity
in the benzene we were using or to the chlorinated diphenyl." [8]
GE's F.R. Kaimer described the HUMAN reaction of GE executives to the
disfigurement and pain of GE workers exposed to PCBs: "[W]e had 50
other men in very bad condition as far as the acne was concerned. The first
reaction that several of our executives had was to throw it out--get it
out of our plant. They didn't want anything like that for treating wire.
But that was easily said but not so easily done. We might just as well have
thrown our business to the four winds and said, 'We'll close up,' because
there was no substitute and there is none today in spite of all the efforts
we have made through our own research laboratories to find one." [8] And so GE executives -- contrary to their personal
ethics -- reached a business decision to continue using PCBs.
Continue to Part 2.
Endnotes
[1] Robert Risebrough and Virginia
Brodine, "More Letters in the Wind," in Sheldon Novick and Dorothy
Cottrell, editors, OUR WORLD IN PERIL: AN ENVIRONMENT REVIEW (Greenwich,
Conn.: Fawcett, 1971), pgs. 243-255.
[2] Soren Jensen, "Report
of a New Chemical Hazard," NEW SCIENTIST Vol. 32 (1966), pg. 612.
[3] Kristin Bryan Thomas and
Theo Colborn, "Organochlorine Endocrine Disruptors in Human Tissue,"
in Theo Colborn and Coralie Clement, editors, CHEMICALLY-INDUCED ALTERATIONS
IN SEXUAL AND FUNCTIONAL DEVELOPMENT: THE WILDLIFE/HUMAN CONNECTION [Advances
in Modern Environmental Toxicology Vol. XXI] (Princeton, N.J.: Princeton
Scientific Publishing Co., [1992).] pgs. 342-343.
[4] See, for example, Robert
L. DeLong and others, "Premature Births in California Sea Lions: Association
With High Organochlorine Pollutant Residue Levels," SCIENCE Vol. 181
(Sept. 21, 1973), pgs. 1168-1170; and Peter J. H. Reijnders, "Reproductive
failure in common seals feeding on fish from polluted coastal waters,"
NATURE Vol. 304 (Dec. 4, 1986), pgs. [456-457.]456-457.
[5] Shinsuke Tanabe, "PCB
Problems in the Future: Foresight from Current Knowledge," ENVIRONMENTAL
POLLUTION Vol. 50 (1988), pgs. 5-28.
[6] Kristin Bryan Thomas and
Theo Colborn, "Organochlorine Endocrine Disruptors in Human Tissue,"
in Theo Colborn and Coralie Clement, editors, CHEMICALLY-INDUCED ALTERATIONS
IN SEXUAL AND FUNCTIONAL DEVELOPMENT: THE WILDLIFE/HUMAN CONNECTION [Advances
in Modern Environmental Toxicology Vol. XXI] (Princeton, N.J.: Princeton
Scientific Publishing Co., [1992).] pgs. 365-394. For the comparison of
U.S. breast-fed infants' intake vs. World health Organization's standard
for adults, see pg. 385.
[7] Hugh A. Tilson and others,
"Polychlorinated Biphenyls and the Developing Nervous System: Cross-Species
Comparisons," NEUROTOXICOLOGY AND TERATOLOGY Vol. 12 (1990), pgs. 239-248.
[8] Cecil K. Drinker and others,
"The Problem of Possible Systemic Effects From Certain Chlorinated
Hydrocarbons," THE JOURNAL OF INDUSTRIAL HYGIENE AND TOXICOLOGY Vol.
19 (September, 1937), pgs. 283-311. Thanks to Bridget Barclay of the Hudson
River Sloop Clearwater for sending us this revealing article. Ms. Barclay
and her colleagues at Hudson Clearwater have worked tirelessly for years
to force a sensible cleanup of PCBs that GE dumped, contaminating the length
of the Hudson River; Hudson Clearwater can be reached in Poughkeepsie at
(914) 454-7673.
Descriptor terms: pcbs; ge; chlorine; sandford brown; halowax
corp; usphs; westinghouse; electricity; monsanto; wildlife; fish; mo; landfills;
oceans; swan corp;
RACHEL'S HAZARDOUS WASTE NEWS #327
---March 4, 1993---
News and resources for environmental justice.
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Environmental Research Foundation
P.O. Box 5036, Annapolis, MD 21403
Fax (410) 263-8944; Internet: erf@igc.apc.org
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