Male births declining in the U.S. and Japan

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Male births declining in the U.S. and Japan

By Amy Norton
Mon Apr 16, 2:41 PM ET



NEW YORK (Reuters Health) - Mother Nature has always ensured that male births outnumber female ones, but the gap has been gradually narrowing over the past three decades in the U.S. and Japan, according to a new study.

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Researchers suspect the decline in male births can be explained, at least in part, by paternal exposure to environmental toxins, such as certain pesticides, heavy metals, solvents or dioxins -- chemical byproducts produced during incineration or the manufacture of other chemicals.

Traditionally, it's been expected that for every 100 girls born, there will be about 105 boys. This balances out the higher death rate among male fetuses and infants. But since 1970, the U.S. and Japan have experienced a downward shift in this male-to-female birth ratio, researchers report in the online edition of the journal Environmental Health Perspectives.

In the U.S., the proportion of boys dropped from 105.5 per 100 girls in 1970 to 104.6 in 2001; in Japan, the male-to-female ratio dropped from 106.3 boys for every 100 girls to just fewer than 105 per 100.

The changes may seem small, but the study authors suspect they are one manifestation of the effects of environmental pollutants on the male reproductive system.

The decline in male births has occurred "at the same time that we've been seeing other signs that male reproductive health is in danger," said lead study author Dr. Devra Lee Davis, a professor of epidemiology at the University of Pittsburgh Graduate School of Public Health.

These other signs, she told Reuters Health, include lower testosterone levels and sperm counts, as well as increases in testicular cancer, a disease that most often affects young men.

Environmental toxins may be a common denominator here, according to Davis and her colleagues. Such exposures may specifically lower rates of male, rather than female, births for a few reasons. They may, for example, affect the viability of sperm that bear the Y chromosome, which determines male sex -- or the viability of male fetuses.

Davis's team found that while fetal deaths have declined overall in recent decades, the proportion of male deaths is growing. In Japan, in particular, male fetuses accounted for about two thirds of all fetal deaths in the 1990s.

Over the years, there have been a number of reports showing that heavy exposure to certain pollutants may affect a man's likelihood of fathering a son.

Men in the Italian town of Seveso who were exposed to large amounts of dioxin through an industrial explosion in 1976 fathered significantly more girls than boys. Similarly, a study of workers at a Russian herbicide plant found that only 38 percent of children born to male workers were boys; female workers, on the other hand, had the expected ratio of male-to-female children.

It's not known whether chronic low-level exposure to toxic chemicals could have similar reproductive effects, according to Davis. But it's important to find out what's behind the decline in male births, she and her colleagues point out.

"The question is, what...level of evidence do we need before we take action," Davis said.

For now, she recommends that people who want to limit their everyday exposure to potentially harmful chemicals read the labels of the household products they buy. For example, she said, "avoid things that say 'fragrance' but don't tell you what it is."

Alternatives include using the various "green" products on the market, as well as old-fashioned cleaning standbys like baking soda and vinegar.

SOURCE: Environmental Health Perspectives, online April 9, 2007.

http://news.yahoo.com/s/nm/20070416/hl_nm/male_births_dc;_ylt=AmJenMD3faQbdVH_NdWExXQR.3QA

Johnny

Not sure if the declining birthrate in Japan is due to chemicals in the food supply as much as the young Japanese failing to reproduce. Japan has an inverted demographic projection. The dwindling supply of workers who pay into the tax base will be overwhelmed by the receivers of government programs 
Openly Straight.

Mr. X

Plus building those Godzilla sized robots gets to be really expensive.
Feminists - "Verbally beating men like dumb animals or ignoring them is all we know and its not working."

Pacman7331

Yep masculinity is a endangered species.
In fact it's just going extinct.
Add that to the list.   

Cya on the other side of ∞

:clock:

The sun sets in the west.
Rises in the east.





Pacman7331

http://www2.canada.com/windsorstar/news/story.html?id=fffbfc6d-38c4-463b-8b8a-6f2d367b1c5f


The disappearing male
Studies show rise in birth defects, infertility among men
Sonja Puzic, Windsor Star
Published: Thursday, November 06, 2008



Are males becoming an endangered species?
That's the question scientists and researchers have been pondering since alarming trends in male fertility rates, birth defects and disorders began emerging around the world.
More and more boys are being born with genital defects and are suffering from learning disabilities, autism and Tourette's syndrome, among other disorders.
Male infertility rates are on the rise and the quality of an average man's sperm is declining, according to some studies.
But perhaps the most disconcerting of all trends is the growing gender imbalance in many parts of heavily industrialized nations, where the births of baby boys have been declining for many years.
What many scientists are calling the most important -- and least publicized -- issue surrounding the future of the human race will be highlighted in a CBC documentary that features two Windsor researchers who've studied the phenomenon.
Titled The Disappearing Male and premiering tonight at 9 on CBC-TV, the documentary includes interviews with Jim Brophy and Margaret Keith, adjunct sociology professors at the University of Windsor.
They have been studying the decline in the birth of male children in the Aamjiwnaang First Nation community located next to the infamous Chemical Valley, Canada's largest concentration of petrochemical plants, near Sarnia.
A paper co-authored by Keith and published three years ago in the U.S. journal Environmental Health Perspectives suggests that exposure to various chemicals produced by industrial plants surrounding the Aamjiwnaang reserve land may be skewing the community's sex ratio.
The researchers looked at the community's birth records since 1984 and saw "a dramatic drop in the number of boys being born in the last 10 years, particularly in the five-year period between 1998 and 2003," Brophy said.
Of 132 Aamjiwnaang babies born between 1999 and 2003, only 46 were boys. Typically, about 105 boys are born for every 100 girls in Canada.
High miscarriage rates and a unusually high number of children suffering from asthma were also noted by researchers.
Although the link between pollutants and human reproduction has not been firmly established, there is growing evidence that the birth sex ratio can be altered by exposure to certain chemicals, such as dioxin, PCBs and pesticides. Brophy said studies done in the United States, Japan and Europe seem to support the theory that the so-called endocrine disrupting chemicals have a particular effect on males.
Some of these chemicals are found in commonly used products such as baby bottles and cosmetics. They can also cause miscarriages and a "whole host" of disorders in a male child, Brophy said.
Brophy said soil and water contamination in and around the Aamjiwnaang reserve had been documented before, including in a University of Windsor study that found high levels of PCBs, lead, mercury and various chemicals in the area in the late 1990s. Accidental chemical spills in the area have not been uncommon.

GLOBAL AWARENESS

But it wasn't until the Aamjiwnaang birth ratio study was published that the global science community really took notice.
"It triggered ... calls from scientists and researchers from around the world who had been looking at this issue in Europe and the United States," Brophy said. "Aamjiwnaang became almost the poster child."
While Brophy has not seen The Disappearing Male documentary yet, he believes the story of the Aamjiwnaang community will be "the focal point."

He said the documentary also includes interviews with "some of the foremost experts in the world" on environmental effects on reproductive health.
Brophy and Keith have also studied other occupational and environmental exposures to pollutants, including the link between breast cancer and certain types of jobs in the Windsor-Essex region.


Pacman7331

http://www.sustainer.org/dhm_archive/index.php?display_article=vn630spermed

You're Only Half the Man Your Grandfather Was

"Downward Motility" is the title of a January Esquire magazine article about declining human sperm counts. A similar piece in the New Yorker is called "Silent Sperm." The press is beginning to pick up the endocrine disrupter story. Of all environmental scare stories, this one really hits home.

Over the past two generations sperm counts in many parts of the world have fallen by half, and a higher percent of sperm are deformed and unfunctional. Testicular cancer is on the rise, as are birth defects such as undescended testicles. Many kinds of animals are suffering from hormone derangements that produce -- how could the media resist this one? -- masculinized females and feminized males.

These unsettling phenomena are caused by chemicals we throw into the environment, quite a few different kinds of them, which happen, so it seems, to behave like hormones.

Hormones are specific, subtle, fleet, ephemeral message-carriers in the body. They are made in the endocrine glands -- the pituitary, for example, or the adrenals sitting atop the kidneys, or the ovaries or testes. They spread through the body, turning on and off different chemical processes in different cells. Particularly important are the hormones that control reproduction -- estrogen, testosterone, progesterone. Most of us know from our experience of adolescence, pregnancy, menstruation, or menopause that these hormones affect not only our skin, body temperature, and sexuality, but our moods and personalities. They also affect, in ways we are only beginning to understand, the growth and division of cells, which means both our ability to have children and our propensity to get cancer.

Hormones work by fitting into special cellular receptors designed to receive them as a lock is designed to receive a particular key. This is where endocrine disrupters come in. They are foreign chemicals -- PCBs, dioxins, many pesticides, some common ingredients in plastics, detergents, and cleaning agents -- that happen, by chemical accident, to fit into hormone receptors. There they may mimic hormones, turning on cellular processes that in fact shouldn't be turned on. Or they may simply block the receptors, preventing the real hormones from getting through.

Bollixing up one of the main information systems of the body can be problematic enough in an adult. In a developing fetus it can be disastrous. Infinitesimal concentrations of an endocrine disrupter hitting a fetus at the wrong moment of unfolding can derail development, change the sex or sexuality of the unborn child, or, most insidiously, affect its future ability to generate sperm or egg cells. The resulting defects may appear only in the next generation, if there is a next generation.

Endocrine disrupters will probably hit a publicity climax in March, when a readable book called Our Stolen Future will be released by Dutton. (In the interest of fair disclosure, I should say that I know the three authors -- biologists Theo Colborn and J.P. Myers and journalist Dianne Dumanoski.) The book is meticulous in describing the research that has led to present understanding of endocrine disruption. But most of us who have followed the story are apprehensive that we are about to see another typical media cycle of overdramatized gloom followed by denial.

The gloom will come naturally from the topic of impaired masculinity. The chemical industry is all set to produce the denial. Watch for the standard responses perfected by the tobacco industry. Those extremists always raise false alarms. Chemicals like these already exist in nature. You can't prove what caused that effect. But people want those products. But regulation would cost money and jobs.

As the action and reaction rage, it would help to keep three facts in mind:

1. This story is not just about sperm. Endocrine disrupters affect the fertility of females as well as males. They disturb other processes in addition to reproduction. The sperm count is what makes the headlines, but the story is much bigger than that.

2. It is not just about humans. In fact the picture was pieced together primarily by Theo Colborn, a wildlife biologist, who saw common problems in Great Lakes fish and Arctic bears, seabirds and alligators, seals and otters. Endocrine chemistry is common to most higher forms of life, and so is endocrine disruption.

3. It is not just about chlorine. Many potent endocrine disrupters, such as dioxins, DDT, and PCBs, are organic molecules with chlorine atoms attached. They are especially noxious because they are stable for a long time in the environment and they are fat-soluble, so they accumulate in living tissue. But beware of a clarion call to "ban chlorine." All endocrine disrupters are not chlorinated, and all organochlorines are not endocrine disrupters.

After the hype is over, I hope we'll see the enduring lessons in these new biological discoveries. Chemicals, unlike people, should be assumed guilty until proven innocent. When we throw them out into the environment in million-ton quantities, they have ways of getting back into us, or into our children. As long as we are able to have children, anyway.

You see, the gloom is hard to resist. This story is really scary.

(Donella H. Meadows is an adjunct professor of environmental studies at Dartmouth College.)

Captain Courageous

On the other side of the coin, males in the Netherlands seem to be doing just fine.
They are even taller than males in most of the industrialized West. Their diet is cited as the cause for this, particularly the dairy products. They've also had a more casual and accepting attitude toward sex in general. The theory about environmental toxins and pollution may still hold up, as the Netherlands' reclamation of land from the sea produces new territory that's got to be cleaner than the old.

Men's Rights Activist

Life, Liberty, & Pursuit of Happiness are fundamental rights for all (including males), & not contingent on gender feminist approval or denial. Consider my "Independence" from all tyrannical gender feminist ideology "Declared" - Here & Now!

Men's Rights Activist

Life, Liberty, & Pursuit of Happiness are fundamental rights for all (including males), & not contingent on gender feminist approval or denial. Consider my "Independence" from all tyrannical gender feminist ideology "Declared" - Here & Now!

Men's Rights Activist

Life, Liberty, & Pursuit of Happiness are fundamental rights for all (including males), & not contingent on gender feminist approval or denial. Consider my "Independence" from all tyrannical gender feminist ideology "Declared" - Here & Now!

Johnny

You seem anxious to say something brother so lets hear it.
Openly Straight.

Vet/Father

Add to this...Growing radiations

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