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#267 - Popular Solvent, TCE, Seems To Cause Serious Birth Defects In Animals, Humans, 07-Jan-1992

The solvent trichloroethylene or TCE is the contaminant found most
often at hazardous waste dumps and in groundwater (underground water
supplies). The federal government has found TCE at 614 (47%) of the
nation's 1300 official Superfund sites. [1, pg. 1] TCE causes leukemia
and liver cancer in laboratory animals and it may cause leukemia in
humans, though the studies showing this have been challenged. [2, pgs.
185-187.]

There is substantial recent evidence that TCE causes birth defects in
newborn animals and is associated with similar defects in humans;
specifically, TCE exposure causes heart defects in baby chickens and
rats [5], and is associated with similar defects in human newborns [6].
Heart defects are the fastest-growing type of birth defects in the U.S.
population [3].

TCE is mainly used as a degreasing solvent in the metal products and
automotive industries, though it can also be found in some typewriter
correction fluids, paint removers/strippers, adhesives, spot removers,
and rug-cleaning fluids. [1, pgs. 69, 71]

Humans invented TCE; it does not occur in nature, so the human body has
not had an opportunity to develop detoxifying or other protective
mechanisms specific to TCE. In 1990 only two U.S. companies
manufactured trichloroethylene (Dow Chemical in Freeport, TX, and PPG
Industries at Lake Charles, LA) but each of the 50 states has large
industrial users of TCE--some 878 major users in all [1, pg. 70], plus
countless smaller users. Total U.S. estimated use of TCE exceeded 200
million pounds in 1990. All 200 million pounds entered the general
environment sooner or later.

When it gets loose, TCE has a strong tendency to enter the atmosphere.
Average air concentrations for TCE range from 0.04 ppb [parts per
billion] in Portland, Oregon in 1984, to 0.29 ppb in Philadelphia in
1983-84, and 0.1 to 0.225 ppb in 10 major cities across the country in
1980-81. The air over six landfills in New Jersey ranges from 0.08 to
2.43 ppb TCE (maximum: 12.3 ppb). But even remote, unspoiled areas have
TCE in their air; in the Arctic in 1982-83 air averaged 0.008 to 0.009
ppb TCE. In other words, the whole atmosphere is contaminated with TCE
at low concentrations.

Any particular molecule of TCE only remains in the atmosphere a few
days. Rain brings TCE back to the ground where it then moves into
streams, rivers, lakes, and oceans. Once it enters water, much of it
moves back into the atmosphere quickly, but some of it enters plants,
then small animals, then fish. Fish from various waterways contain TCE
in the range of 10 to 100 ppb. Clams and oysters in Louisiana contain
TCE (0.8 to 5.7 ppb). Snow in Alaska contains TCE (0.03 to 0.039 ppb).
Rain contains TCE. So naturally, fresh tomatoes, potatoes, apples and
pears contain TCE (1.7, 0-3, 5 and 4 ppb, respectively). [1, pgs. 77-
85]

It helps to understand that EPA [U.S. Environmental Protection Agency]
has set 5 ppb as the maximum allowable concentration in drinking water-
-so finding 5 ppb in a fresh apple should give us pause. Many
processsed foods contain TCE because they are often made with water
contaminated with TCE. The federal Agency for Toxic Substances and
Disease Registry [ATSDR] reports: Chinese-style sauce (28 ppb), quince
jelly (40 ppb), chocolate sauce (50 ppb), grape jelly (20 ppb). Fresh
bread contains 7 ppb, various brands of margarine contain 440 to 3600
ppb. These are not national averages, so the foodstuffs in your
refrigerator may contain less or more than these values.

In sum, we industrial humans have managed to spread TCE everywhere.

Humans ingest TCE by drinking fluids, by breathing, and through their
skin. In 133 American cities, TCE averaged 0.47 ppb in water samples at
the tap. If you take a shower in such water, you inhale considerable
TCE but you also absorb an equal amount through your skin. [2, pg. 117]

All of this explains why Americans have measurable amounts of TCE on
their breath.

There is no doubt that TCE causes leukemia in animals. But the evidence
for leukemia in humans is not so clear. People at Woburn,
Massachusetts, drinking a TCE-contaminated water supply, did get
leukemia in unusually high numbers but some people in the communty also
got leukemia even though they had a different water supply, so the
picture is not crystal clear. [1, pgs. 35-36]

In 1990, two studies were published linking TCE to heart defects. A
large group of people in Tucson, Arizona, drank TCE-contaminated water
for up to a decade. A careful study of children born to these families
revealed an unusually large number of birth defects of the heart. Among
these children, the chances of being born with a heart defect were
three times the normal chances of having such a defect. [6] Earlier
studies of baby chicks, and in 1990 of baby rats [5] revealed that TCE
causes heart defects in these species. Although cause-and-effect has
not been shown to a scientific certainty by the Tucson study, after
reading the available evidence, pregnant women will almost certainly
want to minimize their exposure to TCE. The families in Tucson were
drinking water that contained from 6 to 200 ppb of TCE.

Another long-term effect of TCE exposure was revealed in a 1988 study
of nerve function in people in Woburn, Massachusetts who had been
drinking water contaminated with TCE (118 to 267 ppb). The people had
stopped drinking the contaminated water six years prior to the test,
yet there was unmistakable evidence of damage to their cranial (brain)
nerves. [4]

In addition, there is now a growing body of medical and scientific
literature showing associations between exposure of men to solvents
(including TCE) in the workplace, and birth defects and cancers in
their children. [8, 9] Damage to the men's sperm is the suspected
mechanism for effects in the children.

TCE evaporates easily and is difficult to control. It is representative
of a large number of chlorinated chemicals that now appear to be more
dangerous than we previously knew. Subtle but important health effects,
which were never looked for during previous decades, are now being
discovered. The more we look, the more bad news we learn.

Our present industrial patterns--called loosely "business as usual"--do
not appear to be sustainable.

--Peter Montague

=====

[1] Agency for Toxic Substances and Disease Registry [ATSDR]. DRAFT
TOXICOLOGICAL PROFILE FOR TRICHLOROETHYLENE. Atlanta, GA: Agency for
Toxic Substances and Disease Registry [Division of Toxicology, Mail
Stop E-29, Atlanta, GA 30333], October, 1991. Free as long as supplies
last but requests must be in writing.

[2] Anthony B. Miller and others, ENVIRONMENTAL EPIDEMIOLOGY VOL. 1;
PUBLIC HEALTH AND HAZARDOUS WASTES (Washington, DC: National Academy
Press, 1991).

[3] Larry D. Edmonds and Levy M. James, "Temporal Trends in the
Prevalence of Congenital Malformations at Birth Based on the Birth
Defects Monitoring Program, United States, 1979-1987," MMWR [MORBIDITY
AND MORTALITY WEEKLY REPORT] CDC [CENTERS FOR DISEASE CONTROL]
SURVEILLANCE SUMMARIES, Vol. 39 No. SS-4 (December, 1990), pgs. 19-23.

[4] Robert G. Feldman and others, "Blink Reflex Latency after Exposure
to Trichloroethylene in Well Water," ARCHIVES OF ENVIRONMENTAL HEALTH
Vol. 43, No. 2 (March/April, 1988), pgs. 143-148.

[5] Brenda V. Dawson and others, "Cardiac Teratogenesis of
Trichloroethylene and Dichloroethylene in a Mammalian Model," JOURNAL
OF THE AMERICAN COLLEGE OF CARDIOLOGY Vol. 16, No. 5 (November 1,
1990), pgs. 1304-1309.

[6] Stanley J. Goldberg, "An Association of Human Congenital Cardiac
Malformations and Drinking Water Contaminants," JOURNAL OF THE AMERICAN
COLLEGE OF CARDIOLOGY Vol. 16, No. 1 (July, 1990), pgs. 155-164.

[7] M.K. Smith and others, "Development Effects of Dichloroacetic Acid
in Long-Evans Rats," TERATOLOGY Vol. 39 (1989), pg. 482.

[8] John M. Peters and others, "Brain Tumors in Children and
Occupational Exposure of Parents," SCIENCE Vol. 213 (July 10, 1981),
pgs. 235-236.

[9] Helena Taskinen and others, "Spontaneous abortions and congenital
malformations among the wives of men occupationally exposed to organic
solvents," SCANDINAVIAN JOURNAL OF WORK, ENVIRONMENT AND HEALTH Vol. 15
(1989), pgs. 345-352.

Descriptor terms: birth defects; health; reproductive hazards;
trichloroethylene; hazardous waste landfills; heart defects; dow
chemical; ppg industries; nj; arctic; clams; oysters; la; ak; epa;
atsdr; leukemia; cancer; carcinogens; woburn, ma; ma; occupational
safety and health; occupational safety and health; solvents;