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#327 - How We Got Here -- Part 1 The History Of Chlorinated Diphenyl (PCBs), 03-Mar-1993

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

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.

[To be concluded next week.]

--Peter Montague


[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,
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,
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-

Descriptor terms: pcbs; ge; chlorine; sandford brown; halowax corp;
phs; westinghouse; electricity; monsanto; wildlife; fish; mo;
landfilling; oceans; swan corp;

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