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#448 - Another Study Shows Sperm Loss, 28-Jun-1995

Researchers in Belgium have reported a new study showing a
deterioration in sperm quality in young Belgian men since 1977.[1] The
study provides new evidence supporting the hypothesis that sperm
quality has been deteriorating for 50 years among men in industrialized
countries. The Belgian study of 360 men (90% of them in the age group,
21 to 30) found a statistically-significant reduction in sperm density
(number of sperm per milliliter of semen), as well as an increase in
misshapen sperm and in sperm with low motility (ability to swim or
move). (A milliliter is one thousandth of a liter, and a liter is about
a quart.)

The Belgian study compared men in 1977 to men in 1994 and reported
that, in 1977, 39.6% of sperm had a normal shape, but in 1994, the
percentage of normal sperm had dropped to 27.8%. The average number of
sperm with strong motility dropped from 53.4% in 1977 to 32.8% in 1994.
Methods of analysis were unchanged between 1977 and 1994, the
researchers reported. The new study was described at the 10th annual
(1994) meeting of the European Society of Human Reproduction and
Embryology and has not been fully published.[1] The new finding follows
on a report earlier this year in the NEW ENGLAND JOURNAL OF MEDICINE,
that sperm from men in Paris, France has deteriorated in quantity and
quality during the past 20 years.[2] The NEW ENGLAND JOURNAL OF
MEDICINE report, itself, followed on an earlier study showing
deteriorating sperm during the last 20 years among men in Scotland.[3]
(See REHW #432.)

In what may be a related finding, researchers in Denmark in 1994
reported a much higher sperm count in organic farmers compared to blue-
collar workers (welders and printers).[4] Organic farmers avoid the use
of chemical fertilizers and pesticides and tend to eat a diet high in
chemical-free vegetables and dairy products. The small group (30 men)
had sperm densities more than twice as high as blue-collar workers (363
million sperm per milliliter of semen vs. 164 million per milliliter).
The researchers reported that this finding was "unexpected" and that
they could provide no plausible reason for the finding.

In the U.S., chemical-industry-sponsored researchers have begun to
attack the original study which suggested that sperm density is
dropping among men in industrialized countries. In 1992, a historical
analysis of 62 separate sperm-count studies, by Elisabeth Carlsen,
concluded that sperm count among men throughout the industrialized
world has declined by about 50% during the past 50 years.[5] In 1994
this finding was challenged by researchers who said that it might have
been caused by Carlsen's erroneous choice of statistical methods, not
by an actual decline in sperm count.[6] Carlsen and her colleagues
defended their choice of statistical method (they had used a simple
linear model), saying their critics had simply misunderstood what they
had said and done. Now a new attack on the Carlsen hypothesis has been
published by researchers from Dow Chemical and Shell Oil Company.[7]
The Dow and Shell researchers show that the use of more complex
statistical models allow one to conclude that sperm count has been
INCREASING among men during the past 20 years, not decreasing. The Dow
and Shell researchers do not comment on the most recent empirical
studies, from France, Scotland, and Belgium, showing decreases.

In related research, a scientist sponsored by the Chemical
Manufacturers Association (CMA) has attacked the whole idea that
estrogen-like industrial chemicals may be causing a host of ailments in
men and women, including breast cancer, endometrial cancer, testicular
cancer, birth defects of the penis, undescended testicles, reduced
sperm count and sterility. Danish scientists had hypothesized that all
these ailments may be related to several dozen chemicals known to mimic
the female sex hormone, estrogen.[8] Now Professor Stephen Safe argues
that natural estrogen-mimicking chemicals in plants that we eat far
outweigh any effects we might experience from human-created industrial
chemicals.[9] "The suggestion that industrial estrogenic chemicals
contribute to an increased incidence of breast cancer in women and male
reproductive problems is not plausible," Professor Safe concludes.

To support his conclusion, Professor Safe had to ignore many parts of
the problem.[10] For example, as the British medical journal, LANCET,
notes, "Phyto-oestrogens from plants are ingested daily but are readily
metabolised and excreted." The LANCET's point is that naturally-
occurring estrogen-like chemicals in plants enter the human body in our
food, but they are also broken down quickly, and leave the body.
Industrial chemicals may be stored in the body and mimic hormones for
long periods, years or decades, giving them long opportunities to
affect a person's endocrine system, nervous system, and immune system.
Even very weakly estrogenic chemicals may be important if they remain
in the body for long periods.

Furthermore, Professor Safe doesn't mention that the problem is one of
hormone balance and imbalance. All humans (males and females) contain
both androgens (male hormones) and estrogens (female hormones); thus
chemicals that mimic androgens or estrogens, or chemicals that
interfere with the body's use of androgens or estrogens, may disrupt
the healthy balance of sex hormones. Professor Safe concludes that a
chemical can be disregarded if it has no demonstrated estrogen-like
activity. For example, he dismisses p-p'-DDE (a breakdown byproduct of
the pesticide, DDT) as a cause of human problems because it does not
mimic estrogens. However, as we saw last week (REHW #447), p,p'- DDT is
now known to be a potent anti-androgen, and the class of chemicals
called anti-androgens may be responsible for many of the effects
attributed to estrogen-mimicking chemicals, including cancer and
reproductive disorders in both women and men. The problem is far more
complex than Professor Safe seems to think it is.

Professor Safe examines four estrogen-mimicking pesticides to which we
are all exposed via our daily diet (DDT, dieldrin, endosulfan, and
p,p'-methoxychlor). He then generalizes about the effects of these four
pesticides, concluding that "dietary exposure to xenoestrogens [non-
natural estrogen-mimicking chemicals] derived from industrial chemical
residues in foods is minimal compared to the daily intake of [estrogen-
like chemicals] from naturally-occurring [sources in our food]."[9] But
four pesticides do not represent all of the non-natural sources of
estrogen-like chemicals in our diet. On the contrary, the industrial
gender-bending chemicals in our diet remain largely unidentified. Just
this month, researchers reported that the resin used to line 85% of the
tin cans in the U.S. leaks estrogen-like chemicals into the food inside
the cans.[11] Professor Safe's conclusion, that industrial chemicals
are irrelevant to your hormones, is premature, to say the least.

The estrogen hypothesis --especially as it relates to breast cancer --
has been given increased credibility by recent analyses in the
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES.[12] Even Dr. Bruce
Ames --notorious for arguing that industrial chemicals hardly ever hurt
anyone (see REHW #398)--now seems to agree that sex hormones are
related to as much as 30% of all cancer cases.[13]

The endocrine system in humans and wildlife is as complicated as the
central nervous system. It controls reproduction, growth, development,
and behavior, particularly gender-related behavior. It will be decades
--or centuries --before it is understood. Tinkering randomly with the
hormones in such a system seems, on the face of it, dangerous and
unwise.

Meantime, while various scientists are making a good living tinkering
and arguing among themselves, 46,000 American women will die of breast
cancer this year and another 182,000 will undergo surgery, radiation
treatment or chemotherapy for the disease. The 40-or-so chemicals that
have already been identified as hormone-mimickers are still being
pumped and dumped into the environment in billion-pound quantities each
year. We allow this to happen because we (as a society) assume
chemicals are innocent until proven guilty. Isn't it time we turned
that assumption on its head, requiring corporate polluters to
demonstrate the absence of harm from their products before they are
released? Why do we tolerate this chemical trespass into our most
intimate property, our bodies? The present regulatory system, which is
GUARANTEED to cause great harm before we can even begin to restrict the
output of dangerous chemicals, seems--to put it bluntly --so unworthy
of a great nation, so uncivilized.

--Peter Montague

=====

[1] K. Van Waeleghem and others, "Deterioration of sperm quality in
young Belgian men during recent decades," HUMAN REPRODUCTION Vol. 9,
Supplement 4 (1994), pg. 73; this is an abstract, not a full report.

[2] Jacques Auger and others, "Decline in Semen Quality Among Fertile
Men in Paris During the Past 20 years," NEW ENGLAND JOURNAL OF MEDICINE
Vol. 332, No. 5 (February 2, 1995), pgs. 281-285.

[3] D. Stewart Irvine, "Falling sperm quality," BRITISH MEDICAL JOURNAL
Vol. 309 (August 13, 1994), pg. 476.

[4] Annette Abell and others, "High sperm density among members of
organic farmers' association," THE LANCET Vol. 343 (June 11, 1994), pg.
1498. Thanks to Marjorie Fisher for sending us a copy of this article.

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

[6] Peter Bromwich and others, "Decline in sperm counts: an artefact of
changed reference range of 'normal'?" BRITISH MEDICAL JOURNAL Vol. 309
(July 2, 1994), pgs. 19-22. Elisabeth Carlsen and some of her co-
workers responded that Bromwich's analysis was "based on wrong
assumptions" and "failed to give any empirical reference that might
support [Bromwich's] assertion of differential selection." See Niels
Keiding and others, "Importance of empirical evidence," BRITISH MEDICAL
JOURNAL Vol. 309 (July 2, 1994), pg. 22.

[7] Geary W. Olsen and others, "Have sperm counts been reduced 50
percent in 50 years? A statistical model revisited," FERTILITY AND
STERILITY Vol. 63, No. 4 (April, 1995), pgs. 887-893. Thanks to Jeff
Pitt for sending us a copy of this article.

[8] Devra Lee Davis and others, "Medical Hypothesis: Xenoestrogens As
Preventable Causes of Breast Cancer," ENVIRONMENTAL HEALTH PERSPECTIVES
Vol. 101 (October 1993), pgs. 372-377. And: Richard M. Sharpe and Niels
E. Skakkebaek, "Are oestrogens involved in falling sperm counts and
disorders of the male reproductive tract?" THE LANCET Vol. 341 (May 29,
1993), pgs. 1392-1395.

[9] Stephen H. Safe, "Environmental and Dietary Estrogens and Human
Health: Is There a Problem?" ENVIRONMENTAL HEALTH PERSPECTIVES Vol.
103, No. 4 (April, 1995), pgs. 346-351.

[10] Anonymous, "Male reproductive health and environmental oestrogens
[editorial]," THE LANCET Vol. 345 No. 8955 (April 15, 1995), pgs. 933-
935.

[11] Jose Antonio Brotons and others, "Xenoestrogens Released from
Lacquer Coatings in Food Cans," ENVIRONMENTAL HEALTH PERSPECTIVES Vol.
103, No. 6 (June 1995), pgs. 608-612.

[12] Satyabrata Nandi and others, "Hormones and mammary carcinogenesis
in mice, rats, and humans: A unifying hypothesis," PROCEEDINGS OF THE
NATIONAL ACADEMY OF SCIENCES USA Vol. 92, No. 9 (April 25, 1995), pgs.
3650-3657.

[13] Bruce N. Ames and others, "The causes and prevention of cancer,"
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES USA Vol. 92, No. 12
(June 1995), pgs. 5258-5265.

HOW TO RESEARCH TOXIC CHEMICALS

We have just published HOW TO RESEARCH CHEMICALS: A RESOURCE GUIDE, 88
pages. In it, author Maria Pellerano offers citizen-activists a clear
introduction to toxic chemicals, including extensive information on
various resources that are available to help you learn about a
chemical's toxicity. It includes descriptions and ordering information
for many books and other useful resources such as low-cost online
databases, plus descriptions of organizations that can help you in your
research. Some of the expensive printed resources should be ordered
through your public library. To help you get good chemical-related
resources into your public library, we have included an essay by Laura
Powers of Libraries for the Future on "Seeking Information on Chemicals
Through Your Public Library." To order this new publication, please
send a check for $10.00 to: Environmental Research Foundation, P.O. Box
5036, Annapolis, MD 21403-7036. If you would like to place a
Visa/Mastercard order, please call (410) 263-1584. For international
orders, add $5.00 for postage and only Visa or Mastercard payments can
be accepted.

Descriptor terms: research guides; chemical toxicity; chemicals and
health; computerized databases; libraries; endocrine disrupters;
belgium; sperm count; sperm quality; male reproductive health; sperm
motility; sperm shape; european society of human reproduction and
embryology; paris, france; france; scotland; denmark; organic farmers;
welders and welding; painters and painting; dow chemical; shell oil;
chemical manufacturers association; stephen safe; androgens; estrogen;
ddt; endosulfan; methoxychlor;