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attached: male estrogenics media coverage

  as an attachment, reuters, A>P., Science News & the press release from this
  Pollution from PCBs Keeps GE in Trouble With Pittsfield, Mass.
  The Wall Street Journal, December 4, 1997, ppA1, A6.
       The General Electric company used polychlorinated biphenyls
  (PCBs) for many different uses for decades. These chemicals are
  now causing an uproar in Pittsfield, Massachusetts.
       PCBs were banned as a probable cause of cancer in 1976. In
  Pittsfield, GE has been working to contain or remove the
  chemicals at its 250-acre plant.
       Tests done around the area indicate unsafe levels of PCBs.
  One lot measured 20,000 parts per million and another 44,000 ppm.
  The safe level for residential lots is no more than 2 parts per
       The rising number of homes found contaminated has alarmed
  local residents. GE's capping proposals provoked outrage.
       "No capping. Removal, removal, removal," said one man at a
  recent town meeting. "My kids are playing out there. I don't want
  them dying of cancer," said a housewife.
       GE has agreed to move at least 30,000 tons of earth from
  home sites in the area.
       A state study showing low PCB levels in residents' blood has
  helped the company but it still faces problems. Eighteen
  homeowners have sued in federal court for damages from diminished
  property values. The Massachusetts attorney general is
  investigating claims that GE covered up internal memos that might
  have shown the presence of PCBs in a donated landfill years
  earlier. EPA is investigating similar issues.
       GE executives claim the dangers of PCBs are exaggerated.
  "This thing has been blown way out of proportion," said Stephen
  Ramsey, GE's vice president for environmental programs.
       One environmental regulator believes the company magnified
  its problems by trying to manage the PCB problems by capping
  them, which he considers only a quick inadequate fix for
  residential properties. Ramsey contends that it's "a misperception
  that it's a cheap, cheesy remedy that doesn't work."
       The article details the recent history of the PCB problem in
  Pittsfield including GE attempts to control the problem, EPA and
  state level investigations into the company's actions and public
  Wednesday December 3 6:00 PM EST		Estrogens Influence Male Fertility
  NEW YORK (Reuters) -- Experts say estrogen, the 'female' hormone, may
  strongly influence male fertility and help shape masculine growth and
  "Estrogens may exert more widespread effects in the male and, remarkably,
  they may even be essential for (male) fertility," said Dr. Richard Sharpe,
  a fertility expert at the MRC Reproductive Biology Unit in Edinburgh,
  Sharpe's commentary appears in this week's issue of the journal Nature,
  which also includes an American study investigating the links between
  estrogen and male fertility. (snip)
  Scientists at the University of Illinois in Urbana, Illinois, focused on
  the high concentrations of estrogen found in an area of the male
  reproductive system known as the efferent ducts. These ducts serve as
  pooling areas for sperm produced by the testes. The researchers say
  estrogen present in these ducts seems to trigger the reabsorption of up to
  90% of the fluid surrounding freshly produced sperm, "thereby increasing
  the concentration of sperm" before its (eventual) ejaculation. (snip)
  The Illinois findings run counter to recent speculation that the ingestion
  of environmental pollutants mimicking the effects of estrogen may actually
  lower male fertility. Sharpe theorizes that "under some circumstances,
  estrogens may inhibit rather than promote (efferent duct) fluid
  SOURCE: Nature (1997;390:449-450, 509-512)
      [CNN logo]             [Health banner] [Taking the pulse of family
  health & fitness]
                       NEW YORK (AP) -- Most people consider estrogen a
                       female hormone, but men make it too. A new study
                       suggests one reason why: Estrogen may help men
                       stay fertile by preventing a plumbing problem in
                       the reproductive system.
                       The study, done in mice, marks the first time
                       scientists have specified a detailed role for
                       estrogen in the male reproductive tract.
                       The topic is timely because of recent assertions
                       that some environmental chemicals may be reducing
                       sperm counts and otherwise harming male
                       reproductive health by disrupting hormonal
                       signaling. The new study, published in Thursday's
                       issue of the journal Nature, may help research
                       into the issue.
                       It also might help scientists develop a male
                       contraceptive, said the study's lead author, Rex
                       Hess of the University of Illinois.
                       Estrogen acts by binding to structures called
                       receptors in cells. There are at least two kinds
                       of estrogen receptors, and last year scientists
                       reported that male mice that lacked one kind were
                       Using mice that lacked one of the estrogen
                       receptors, researchers found that tubes that
                       transport sperm and fluid in these mice fail to do
                       an important job: absorbing a lot of that fluid.
                       That absorption concentrates substances in the
                       fluid that help the sperm mature, and also
                       concentrates the sperm to ensure a large dose for
                       Copyright 1997   The Associated Press. All rights
                       reserved. This material may not be published,
                       broadcast, rewritten, or redistributed.
                             [SCIENCE NEWS ONLINE]
                 [Rule][space]  December 6, 1997 [space] [Rule]
  Estrogen's Emerging Manly Alter Ego	by J. Raloff
       Estrogen is usually described as the animal kingdom's primary
       female sex hormone. That's a gross oversimplification, however.
       Even that quintessentially male preserve -- the sperm -- depends
       on estrogen, scientists report this week. Without estrogen, males
       are infertile.
       The new study, by Rex A. Hess at the University of Illinois at
       Urbana-Champaign and his colleagues, focuses on estrogen's role in
       male reproductive function. Nevertheless, the researchers observe
       that their findings also suggest a mechanism by which DDT and
       other estrogen-mimicking pollutants (SN: 7/3/93, p. 10) could
       wreak havoc on fertility. If these weak estrogens displace the
       body's more potent natural ones, they might diminish estrogen
       exposure -- and sperm activity (SN: 1/22/94, p. 56).
       Hess and his colleagues study mutant mice. These animals were bred
       to produce estrogen normally, but they lack the gene for an
       estrogen receptor -- a protein that allows cells to take up the
       hormone. As a result, the mice cannot respond to the estrogen in
       their bodies.
       Since this hormone plays a pivotal feminizing role in development,
       the scientists expected that mutant females would develop
       abnormally. "The big surprise," notes Patricia M. Saling, a
       reproductive cell biologist at Duke University Medical Center in
       Durham, N.C., was the finding 4 years ago that the males were
       infertile. Since then, Hess and others have been probing why.
       Last year, Mitch Eddy of the National Institute of Environmental
       Health Sciences (NIEHS) in Research Triangle Park, N.C., and his
       colleagues showed that although the mutant males initially make
       sperm, their testes quickly degenerate. They traced the problem to
       a backup of excess seminal fluid.
       In the Dec. 4 Nature, Hess and his colleagues uncover the cause of
       the backup. It's not overproduction of the secreted fluid, as many
       had suspected. Instead, it's a drainage problem: The tubes running
       from the testes to the epididymis, where sperm mature and acquire
       the ability to fertilize eggs, are unable to drain off the excess
       Besides damaging the testes, this excess fluid "also results in a
       very dilute ejaculate," notes Hess' colleague Kenneth S. Korach of
       NIEHS, a developer of the mutant strain of mice. If sperm are not
       packed densely in seminal fluid, fertility is impaired.
       The tubes -- known as efferent ducts -- and the epididymis have
       never been considered "dominant in terms of making or breaking
       fertility," Saling says. The new study suggests otherwise. In
       fact, she says, "if manipulating the epididymal environment can
       lead to whopping amounts of infertility, this would suggest a new
       organ to target in the development of [male] contraceptives."
       Ineffective fluid removal may not explain all of the mutant males'
       fertility problems, however. Eddy's team found that any sperm
       produced fail to mature and become capable of fertilization. Yet
       excess fluid might play a role here, too, speculates Richard M.
       Sharpe of the Medical Research Council in Edinburgh. In a
       commentary accompanying the Nature report, he says that ". . . the
       abnormal amounts of fluid will effectively dilute [any maturing
       agents] secreted within the epididymis."
       What the new data clearly demonstrate, Korach states, is the
       essential role of estrogen in male reproductive health. Indeed,
       Sharpe adds, "Suddenly, the idea of 'male' and 'female' hormones
       begins to look thin."
       Hess' team argues that the new data also raise "further concern
       over the potential direct effects of environmental estrogens on
       male reproduction and reported declines in sperm counts."
       After analyzing 61 studies, Danish scientists reported an apparent
       downward trend in human sperm counts 5 years ago (SN: 1/22/94, p.
       56). Since then, others have challenged their assessment, arguing
       that the data -- collected in different regions, over different
       times, and using different criteria -- are not comparable.
       Not so, concludes a major reanalysis.
       "I think we were the only group that actually got all of the
       original data," says Shanna H. Swan of the California Department
       of Health Services in Emeryville. Her group analyzed the data
       using a series of alternative statistical techniques to see if the
       decline originally reported was an artifact of the way the data
       had been analyzed.
       In the just-published November Environmental Health Perspectives,
       Swan's team reports that all its analyses show a decline in sperm
       counts since 1970 for men in Western countries. Indeed, Swan
       observes, the statistical representations that best fit the data
       detected an even stronger drop than the Danes had reported.
       The new declines average more than 1 percent annually -- or about
       1.5 million sperm per milliliter per year in the United States and
       3 million sperm per milliliter per year in Europe.
                            [Image] [Image] [Image]
       Eddy, E.M., et al. 1996. Targeted disruption of the estrogen
       receptor gene in male mice causes alteration of spermatogenesis
       and infertility. Endocrinology 137(November):4796.
       Hess, R.A., et al. 1997. A role for oestrogens in the male
       reproductive system. Nature 390(Dec. 4):509.
       Sharpe, R.M. 1997. Do males rely on female hormones? Nature
       390(Dec. 4).
       Swan, S.H., E.P. Elkin, and L. Fenster. 1997. Have sperm densities
       declined? A reanalysis of global trend data. Environmental Health
       Perspectives 105(November):1228.
  Further Readings:
       Fackelmann, K. 1996. Study finds no decline in sperm counts.
       Science News 149(June 8):365.
       Raloff, J. 1997. Roller-coaster sperm counts-and births. Science
       News 151(April 5):212.
       ______. 1997. Radical prostates. Science News 151(Feb. 22):126.
       ______. 1997. A new breadth to estrogen's bisexuality. Science
       News 151(Feb. 22):116.
       ______. 1995. A two-decade drop in sperm counts. Science News
       147(Feb. 25):127.
       ______. 1994. That feminine touch. Science News 145(Jan. 22):56.
       ______. 1993. EcoCancers. Science News 144(July 3):10.
       Kenneth S. Korach     Receptor Biology Section
       Laboratory of Reproductive and Developmental Toxicology
       National Institute of Environmental Health Sciences
       National Institutes of Health
       Research Triangle Park, NC 27709-2233
       Patricia Saling     Duke University Medical Center
       P.O. Box 3648     Durham, NC 27710
       Richard M. Sharpe     Medical Research Council
       Reproductive Biology Unit     37 Chalmers Street
       Edinburgh EH3 9EW     United Kingdom
       Shanna H. Swan     Reproductive Epidemiology Section
       California Department of Health Services
       5900 Hollis Street, Suite E
       Emeryville, CA 94608-2008
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                          copyright 1997 ScienceService
  Embargoed For Release: 3 December 1997 at 14:00:00 ET US
  Contact: Jim Barlow	b-james3@uiuc.edu	217-333-5802   U. of Illinois at
  Urbana-Champaign	Estrogen Linked To Sperm Count, Male Fertility
  CHAMPAIGN, Ill. -- Testosterone may be the hormone that makes the man, but
  it is estrogen -- the so-called 'female' hormone -- that gives sperm its
  reproductive punch, a team of researchers report in Thursday's (Dec. 4)
  issue of the journal Nature.
  Estrogen is vital to male fertility -- specifically to sperm count. That
  discovery, coupled with the debate over declining sperm counts worldwide,
  means "we must be concerned about the potential for environmental chemicals
  to influence male reproductive function," said Rex A. Hess, a professor of
  veterinary biosciences at the University of Illinois and principal author
  of the Nature report.
  "If there is a normal function for estrogen in the male, and that function
  is required for normal fertility, then it is logical to hypothesize that
  chemicals that interfere with estrogen receptors may interfere with
  fertility," Hess said. "Until now, there has been no known function for
  estrogen in the male. We have had nothing to focus on. Now we can ask the
  question: Does this chemical or that chemical interfere?"
  Potential environmental influence on fertility, such as exposure to
  pesticides and industrial chemicals, has sparked controversy since 1992,
  when Copenhagen University researchers concluded that sperm counts were
  declining around the world. In late November, a team led by Shanna Swan of
  the California Department of Public Health reached a similar conclusion
  after reconsidering the data from the 61 studies used in the Copenhagen
  The Nature paper focuses on the regulatory role of estrogen-induced fluid
  reabsorption during the transfer of sperm in fluid from the testis through
  the efferent ductules -- a series of small tubes that act like kidneys,
  producing concentrated semen instead of urine -- to the epididymis, where
  sperm mature and are stored.
  "We have found that estrogen regulates fluid reabsorption in the efferent
  ductules of the male," Hess said. "It is important for the uptake of water,
  ions and proteins from the fluid that carries the sperm. The efferent
  ductules are responsible for reabsorbing nearly 90 percent of the water
  from this fluid. Without the reabsorption, the sperm remain diluted and
  therefore incapable of normal maturation in the epididymis."
  The paper is part of three collaborative studies done over seven years on
  male estrogen -- funded in part by the U.S. Department of Agriculture and
  the U. of I.-- by a team that includes Janice Bahr, a professor of
  physiology, molecular biologist David Bunick and Hess.
  In another study, published in the December issue of the Journal of
  Andrology, the researchers report that the number of genes that express
  estrogen receptors in the efferent ductules of rats -- when operating
  normally -- is 3.5 times greater than the estrogen receptor message in the
  female reproductive tract.
  "This means you have a target for estrogen, and there are plenty of targets
  for the estrogen to bind to," Hess said. "It was surprising to find the
  protein in such a high concentration. We knew it would be there, but
  finding so much was unexpected."
  The Nature findings resulted from studies of estrogen function in the
  reproductive tracts of mice, including genetically produced mice whose
  estrogen receptors are non-functional. As in humans, the mice used in the
  research had similarities in their estrogen, estrogen receptors and
  efferent ductules.
  Hess, Bahr and Bunick reported in the 1994 Proceedings of the Estrogens in
  the Environment, that they had found a new source of potential estrogen
  synthesis in males, in the germ cells of the testis and sperm in the
  epididymis of mice, rats and chickens. Similar findings have been made in
  black bears.
  When estrogen receptors are knocked out, the fluid "accumulates at the site
  of production " just as happens when you get a blocked waste pipe and run
  the tap," writes Richard M. Sharpe of the Medical Research Council
  Reproductive Biology Unit in Edinburgh, Scotland, in an accompanying "News
  and Views" article on Hess' findings. "This build-up progressively impairs
  sperm production because of the increased fluid pressure within the
  In 1993, Sharpe theorized that declines in sperm counts might be occurring
  because of a complex interference with hormones involving the hypothalamus
  in the brain and the pituitary gland during development of the testis.
  Now that the research has provided the first recognized physiological
  function for estrogen in males, Hess said, the next step in the research is
  to determine the biochemical action. "We have known that estrogen is
  present in the male, and in high concentrations in the seminal fluids, but
  we did not know why it was there," he said. "Now we can focus on the
  function of fluid reabsorption and on what genes are regulated by the
  "Estrogen is not only important in the female for fertility, but it also
  exerts its influence on the male, from birth to death," Hess said. "We can
  now say that this female hormone is intimately involved in regulating
  fertility in the male, because if you block the estrogen receptor's
  function as we've shown here, you will have infertility. It is very likely
  that this will be a similar finding in humans."
  Coauthors of the Nature paper are Hess, Bunick and Bahr, along with Ki-Ho
  Lee of the U. of I. department of veterinary biosciences; Julia A. Taylor
  and Dennis B. Lubahn of the departments of biochemistry and child health at
  the University of Missouri at Columbia; and Kenneth S. Korach of the
  National Institutes of Health National Institute of Environmental Health
  Sciences at Research Triangle Park, N.C.
  Coauthors of the paper in the Journal of Andrology are Hess, Bunick,
  Lubahn, Bahr, Daniel H. Gist of the department of biological sciences at
  the University of Cincinnati, Amy Farrell and Paul S. Cooke of the U. of I.
  department of veterinary biosciences, and Geoffrey L. Greene of the Ben May
  Institute for Cancer Research at the University of Chicago.