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#372 - PCBs Diminish Penis Size, 12-Jan-1994

Boys in Taiwan exposed to PCBs while in their mothers' womb develop
smaller penises as they mature, compared to normal boys in Taiwan,
according to a brief article this month in SCIENTIFIC AMERICAN.[1] PCBs
(polychlorinated biphenyls) are a group of industrial chemicals
manufactured and released into the environment in megaton quantities by
Monsanto and its licensees between 1929 and 1976.[2]

The finding of small penises among PCB-exposed human males tends to
confirm that humans and wildlife are affected similarly by exposure to
"endocrine-disrupting chemicals" such as PCBs, dioxin, DDT, and dozens
of others. (See RHWN #249, #263, #264, #323, #327, #334, #337, #364,
#365.) The endocrine system, in wildlife and humans, is a complex set
of bodily organs and tissues whose activities are coordinated by
chemical messengers, called hormones, that control growth, development
and behavior. In recent years, evidence has accumulated that several
dozen pesticides and other industrial chemicals mimic, or interfere
with, hormones and thus disrupt the endrocine system. In both wildlife
and humans, it is the reproductive system that seems most prone to
disruption by hormone-like industrial pollutants.

SCIENCE NEWS reported this month that male alligators exposed to
pesticides in Florida are having difficulty reproducing, partly because
their penises are not developing to normal size.[3] SCIENCE NEWS
presented evidence from several sources that males of many wildlife
species (birds, fish, amphibians, and mammals) are being "feminized" by
exposure to low levels of pesticides and other industrial chemicals
that have been released into the environment in huge quantities since
World War II.

The boys in Taiwan were born to mothers who unwittingly consumed PCB-
contaminated rice oil during a 10-month period in 1979. As many as 2000
people consumed the contaminated oil. The children consumed no
contaminated oil themselves; they were exposed before birth to PCBs
that were carried by their mothers' blood and crossed the placenta;
they may have also been exposed shortly after birth by drinking their
mothers' milk. The rice oil contained 100 parts per million (ppm) PCBs
and 0.1 ppm PCDFs [polychlorinated dibenzofurans, a potent dioxin-like
poison].[4] A new mother in the U.S. today has an average of one ppm
PCBs in her breast milk.

The children in Taiwan have been observed medically for many years.
They are known as the "yucheng" (or "oil disease") children. A similar
PCB contamination event ("yusho") occurred in Japan in 1968.

When 115 yucheng children were examined in 1985 they were less
developed than a control group of children on 32 of 33 different
measures. They were delayed, compared to controls, in the age at which
they performed tasks such as saying phrases and sentences, turning
pages, carrying out requests, pointing to body parts, holding pencils,
and catching a ball.

The yucheng children also had a variety of physical defects at birth,
including dark colored heads, faces and genitals, and abnormal nails
that were often dark and ridged, split, or folded.[5]

These children provided the first direct evidence that PCBs are
teratogenic [birth-defect-producing] in humans. Since then, other
studies have shown that American children with "normal" levels of PCBs
in their blood show slight physical, mental and emotional retardation.

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 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 on
tests requiring fine motor coordination.

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. produces detectable effects on motor
maturation and some evidence of impaired infant learning."[6] In North
Carolina, about 5% of the children have so far shown measurable effects
related to PCB exposure, and in a Michigan study of children whose
mothers ate fish from Lake Michigan (almost all of which are
contaminated with PCBs), 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 stages.[7]

The information from Taiwan about male genital development tends to
confirm that PCB exposure in the womb has effects different from, and
more powerful than, those caused by PCB exposure in later life.

The same seems to be true in wildlife as well. Alligator eggs exposed
to DDT or a related pesticide, dicofol, produce male alligators with
abnormal sex hormones (estrogen and testosterone) in their blood,
leading to growth of penises one-third to one- half normal size, and
subsequent reproductive failure.

The Florida panther, an endangered species, is also failing to
reproduce itself. There are only 30 to 50 panthers remaining, and the
reason for the decline has been a mystery. Now researchers have
reported that between 1985 and 1990, 67 percent of male panthers were
born with one or more undescended testicles, a condition known as
cryptorchidism. In England and the U.S., cryptorchidism has more than
doubled in men during the last four decades.[8] Furthermore, some
Florida panthers are sterile and others produce abnormal or deformed
sperm. It was reported last year that sperm count in men in
industrialized countries has dropped 50% during the past 50 years.[9]

Two years ago, researchers at University of Wisconsin reported that low
prenatal [before birth] exposures to dioxin feminized the behavior of
male rats during adulthood, and sharply reduced their production of
sperm.[10] "Indeed," says Janet Raloff in SCIENCE NEWS, "the
researchers concluded, the developing male reproductive system appears
to be more sensitive to the effects of this hormone-like toxicant
[dioxin] than any other organ or organ-system studied."[3]

The ability of industrial chemicals to damage the reproductive systems
of wildlife has been observed since the 1950s when DDT was linked to
eggshell thinning in many bird species,[11] but humans have been slow
to get the message. Petrochemical corporations and agricultural giants
continually dump billions of pounds of endocrine-disrupting toxins into
the environment each year. Government goes along.

Scientists continue to study birds, uncovering new evidence of
reproductive damage. Dr. Michael Fry at University of California,
Davis, has been studying Western gulls on Santa Barbara Island, where
in recent years he has begun to observe "lesbian gulls," meaning
female-female pairing. He attributes this behavior partly to male
gulls' growing indifference to sex. Examination reveals that the male
gulls have feminized sex organs and have been "chemically castrated" by
DDT and other environmental pollutants, Fry says.

Perhaps the new information about small penises in alligators and
humans will finally get the attention of someone high up in Washington.

--Peter Montague


[1] Marguerite Holloway, "Dioxin Indictment," SCIENTIFIC AMERICAN Vol.
270 (January 1994), pg. 25.

[2] Kristin Bryan Thomas and Theo Colborn, "Organo-chlorine 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.

[3] Janet Raloff, "The Gender Benders," SCIENCE NEWS Vol. 145 (January
8, 1994), pgs. 24-27. And see J. Raloff, "Perinatal dioxin feminizes
male rats," SCIENCE NEWS Vol. 141 (May 30, 1992), pg. 359, and Janet
Raloff, "EcoCancers," SCIENCE NEWS Vol. 144 (July 3, 1993), pgs. 10-13.
See also: Bette Hileman, "The Great Lakes Cleanup Effort," C&EN
[CHEMICAL & ENGINEERING NEWS] February 8, 1988, pgs. 22-39; and: Bette
Hileman, "Concerns Broaden over Chlorine and Chlorinated Hydrocarbons,"
C&EN [CHEMICAL & ENGINEERING NEWS] April 19, 1993, pgs. 11-20.

[4] Walter J. Rogan and others, "Congenital Poisoning by
Polychlorinated Biphenyls and Their Contaminants in Taiwan," SCIENCE
Vol. 241 (July 15, 1988), pgs. 334-336.

[5] Gina Kolata, "PCB Exposure Linked to Birth Defects in Taiwan," NEW
YORK TIMES August 2, 1988, pg. C3.

[6] Hugh A. Tilson and others, "Polychlorinated Biphenyls and the
Developing Nervous System: Cross-Species Comparisons," NEUROTOXICOLOGY
AND TERATOLOGY Vol. 12 (1990), pgs. 239-248.

[7] 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. 319-326.

[8] A. Giwercman and N.E. Skakkebaek, "The human testis--an organ at
risk?" INTERNATIONAL JOURNAL OF ANDROLOGY Vol. 15 (1992), pgs. 373-375.

[9] Elisabeth Carlsen and others, "Evidence for decreasing quality of
semen during past 50 years," BRITISH MEDICAL JOURNAL Vol. 305 (1992),
pgs. 609-613.

[10] Thomas A. Mably and others, "IN UTERO and Lactational Exposure of
Male Rats to 2,3,7,8-Tetrachlorodibenzo-P-dioxin. 1. Effects on
1992), pgs. 97-107. And: Thomas A. Mably and others, "IN UTERO and
Lactational Exposure of Male Rats to 2,3,7,8-Tetrachlorodibenzo-P-
dioxin. 2. Effects on Sexual Behavior and the Regulation of Luteinizing
Vol. 114 (May, 1992), pgs. 108-117. And: Thomas A. Mably and others,
"IN UTERO and Lactational Exposure of Male Rats to 2,3,7,8-
Tetrachlorodibenzo-P-dioxin. 3. Effects on Spermatogenesis and
Reproductive Capability." TOXICOLOGY AND APPLIED PHARMACOLOGY Vol. 114
(May, 1992), pgs. 118-126.

[11] For example, see Robert Risebrough and Virginia Brodine, "More
Letters in the Wind," in Sheldon Novick and Dorothy Cottrell, editors,
1971), pgs. 243-255.

Descriptor terms: taiwan; china; pcbs; sexual development; reproductive
system; endocrine system; monsanto; wildlife; penises; hormones;
endocrine disrupters; pesticides; alligators; fl; pcdfs; pcbs; breast
milk; yucheng; yusho, japan; japan; developmental disorders;
teratogens; birth defects; nc; us; michigan; lake michigan; fish;
estrogen; testosterone; florida panther; undescended testicles;
cryptorchidism; sperm count; rats; dioxin; ddt; dde; dicofol; western
gulls; santa barbara island, ca; ca;

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