As the scientific reassessment of dioxin unfolds inside EPA [U.S.
Environmental Protection Agency], one of the stickiest issues is
how to deal with PCBs (polychlorinated biphenyls). PCBs are a
family of 209 separate chemicals, some of which have the same
unpleasant characteristics as dioxins--they interfere in growth
and reproduction, they damage the immune system, they cause
cancer, and they cause these effects in fish, birds, mice, rats,
mink, seals, sea lions, whales, humans and other forms of life.
One key difference between PCBs and dioxins is that there are
much larger quantities of PCBs in the environment, compared to
dioxins. And many major industrial firms have a long track
record of exposing their workers and their neighbors to PCBs.
Therefore, the potential for PCB-related lawsuits and liability
is large. And therefore the political visibility of PCBs inside
EPA is also large.
There is now considerable evidence that humans WITHOUT
OCCUPATIONAL EXPOSURES are being adversely affected by PCBs.
Humans are exposed mainly through food, especially meat and most
especially fish. Two groups of U.S. children have been studied
from birth to age four, looking for effects from the PCBs we all
carry in our bodies. In Michigan, 313 newborns have been studied;
242 of their mothers had eaten PCB-contaminated sportfish from
Lake Michigan. Higher PCB levels in umbilical cords have been
correlated with smaller birth size (including reduced head size,
diminished girth in the chest) and shorter gestation, an effect
also seen in children whose mothers had occupational exposure.
On standardized tests for infant development, higher PCB levels
in the Michigan children were correlated with abnormally weak
reflexes, less responsiveness to stimulation, more jerky,
unbalanced movement, and more startles.
In North Carolina, 912 infants have been followed from birth.
Their mothers had no unusual PCB exposures but, like all
Americans, they carry PCBs in their body tissues. Among 866 North
Carolina infants tested, higher PCBs in mother's milk was
correlated with hypotonicity [loss of muscle tone] and more
abnormally weak reflexes. Subsequent studies of 802 of the North
Carolina children at ages 6 months and 12 months revealed those
with higher levels of PCBs had poorer performance in tests
requiring fine motor coordination. At seven months, a test of 123
of the Michigan children showed higher PCB levels were related to
poorer visual memory. Researchers reviewing the history of these
children conclude, "There is thus consistent evidence that
prenatal exposure to levels of PCBs commonly encountered in the
U.S. produce detectable effects on motor maturation and some
evidence of impaired infant learning." In North Carolina,
about 5% of the children have so far shown measurable effects
related to PCB exposure, and in Michigan somewhat more than 5% of
the children are showing effects.
At age 4, children in the Michigan group with higher PCBs levels
weighed 10% (4 pounds) less than children with lower PCB levels.
The effect was particularly significant in girls. In addition,
the Michigan children were ranked according to an "activity"
index, and higher PCB levels were correlated with children who
were unusually "quiet and inactive." These effects on growth and
behavior were specifically correlated with exposure to PCBs
before birth and not with exposure after birth. This leads
researchers to conclude that PCBs attack the central nervous
system more successfully during its earlier developmental
The Agency for Toxic Substances and Disease Registry (ATSDR) has
identified human populations with potentially high exposures as:
individuals exposed in the workplace, breast-fed infants of
mothers who consume more than 6 pounds (12 meals) of fish per
year, and "people who live in the vicinity of incinerators and
PCB disposal facilities."
How did this situation develop? The Westinghouse story helps us
understand how we got where we are today.
In 1957 Westinghouse began operating a large transformer factory
in Bloomington, Indiana, processing large quantities of PCBs,
which they purchased from Monsanto, the inventor of PCBs. PCBs
don't conduct electricity, but they conduct heat well, and they
are very stable (they don't break down readily) so they make a
nearly ideal fluid for insulating electrical transformers and
PCBs came to the attention of the scientific world in 1966 when a
Swedish scientist revealed that damage to birds that he had
attributed to DDT was actually being caused by PCBs.
In 1968, PCBs came to public attention when it was reported that
1300 Japanese people had become ill from eating PCB-contaminated
rice oil. Many of the PCB-exposed women subsequently gave birth
to children with birth defects. Workers at the Westinghouse plant
in Bloomington say they were never told of any health hazards
from PCBs. On the contrary, when they began to ask questions
after the mass poisoning in Japan, they say, Westinghouse
officials led them to believe PCBs were entirely safe. Jason
Morrow, a former union local president at the plant, recalls
employee meetings in which then-plant manager Donald M. Sauter
"washed his hands and face in what he told workers was liquid
PCBs to convince them not to worry." A Westinghouse spokesman,
Christopher C. Newton, confirmed for BUSINESS WEEK magazine that
Sauter "dipped his hands" into PCBs at a meeting.
Westinghouse and Monsanto insist that they have always told the
world what they knew about PCB toxicity as soon as they knew it.
However, in a letter dated September 15, 1947, E.C. Barnes of
Westinghouse's medical department wrote that long-term exposure
to PCBs "may produce bodily injury which may be disabling or
could be fatal." According to workers now suing Westinghouse for
injuries they say are PCB-related, this information was never
passed along to the people Westinghouse exposed to PCBs day in
and day out for 25 years.
In 1971, fearing lawsuits, Monsanto began requiring its customers
like Westinghouse to sign a waiver relieving it of financial
liability for improper uses of the chemical, thus putting buyers
on notice of possible dangers. That same year a Westinghouse
biochemist named Thomas O. Munson says he received instructions
directly from then-chief executive officer Donald C. Burnham to
study PCB contamination around four Westinghouse plants. In 1972
Munson submitted his report to Westinghouse officials, urging
them to tell the local communities of the massive contamination
he had found and to take remedial action. Instead Westinghouse
kept the Munson report secret and continued to dump liquid PCBs
directly into the local environments, Munson says.
What does the future hold?
Between 1929 and today, Monsanto made, or licensed someone else
to make, a total of 1.2 million tons of PCBs. Of this total,
31% (370,000 tons) has so far escaped into the general
environment. An estimated 4% of original production has been fed
into incinerators, in hopes of destroying it. However, 780,000
tons of PCBs are still in use in transformers and capacitors, or
have been sent to landfills where they are waiting patiently to
escape. Thus the amount waiting to be released into the
environment is approximately twice as large as the amount that
has already been released.
Almost all PCBs released into the environment end up in the
oceans eventually. Because PCBs are not water-soluble but are fat
soluble, they have a marked tendency to accumulate in living
organisms. Marine mammals at the top of the oceanic food chain
are likely to have up to 10 million times more PCBs in their fat,
compared to the concentration of PCBs in the water they live in.
Once they enter the oceans, PCBs build up in the bodies of fish
and then in fish-eating birds and mam-mals. Fish-eating birds and
mammals (seals, sea lions, some whales, and dolphins) have a
distinct inability to metabolize PCBs--they lack certain enzyme
systems that land-based mammals (such as humans) have that speed
the breakdown of PCBs. As a consequence, ocean birds and mammals
accumulate unusually high levels of PCBs in their bodies and pass
the PCBs to their offspring via eggs (birds) and milk (mammals).
Since PCBs released into the environment move into the oceans
readily, in coming decades ocean birds and mammals seem likely to
experience a continuing buildup of PCBs in their flesh. There is
good evidence that PCBs in marine mammals and birds are already
causing major reproductive failure. Therefore, it seems likely
that ocean mammals (whales, seals, sea lions, and dolphins) will
experience increasing reproductive failure and will become
extinct unless substantial efforts are made to prevent the
release of PCBs that are still in use or are stored in landfills.
(See RHWN #144.) At present, no such efforts are under way or
even under discussion.
--Peter Montague (National Writers Union, UAW Local 1981/AFL-CIO)
 Hugh A. Tilson and others, "Polychlorinated Biphenyls and the
Developing Nervous System: Cross-Species Comparisons,"
NEUROTOXICOLOGY AND TERATOLOGY Vol. 12 (1990), pgs. 239-248.
 Tilson, cited above, pg. 245. Some of the human data are also
reviewed on pgs. 53-54 of Syracuse Research Corporation, DRAFT
TOXICOLOGICAL PROFILE FOR POLYCHLORINATED BIPHENYLS (Atlanta, GA:
Division of Toxicology, Agency for Toxic Substances and Disease
Registry, Public Health Service, U.S. Department of Health and
Human Services, October, 1991.) See also, Anthony B. Miller and
others, ENVIRONMENTAL EPIDEMIOLOGY. VOL. 1. PUBLIC HEALTH AND
HAZARDOUS WASTES (Washington, DC: National Academy Press, 1991).
pgs. 204-205, [207,] 208-210; and see Joseph L. Jacobson and
others, "Effects of in utero exposure to polychlorinated
biphenyls and related contaminants on cognitive functioning in
young children," JOURNAL OF PEDIATRICS Vol. 116 (January, 1990),
 Joseph L. Jacobson and others, "Effects of Exposure to PCBs
and Related Compounds on Growth and Activity in Children,"
NEUROTOXICOLOGY AND TERATOLOGY Vol. 12 (1990), pgs.
 Syracuse Research Corporation, cited above, pg. 140.
 Michael Schroeder, "Did Westinghouse Keep Mum on PCBs?"
BUSINESS WEEK August 12, 1991, pgs. 68-70.
 Shinsuke Tanabe, "PCB Problems in the Future: Foresight from
Current Knowledge," ENVIRONMENTAL POLLUTION Vol. 50 (1988), pgs.
 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.
Descriptor terms: pcbs; epa; lake michigan; nc; prenatal
exposure; atsdr; westinghouse; donald sauter; monsanto; munson
report; ocean mammals; bioaccumulation; mi; health; studies;