As Carlsen and her co-workers said in 1994, defending their 1992 conclusion:  "The most cautious conclusion that can be drawn from the existing data is that semen quality has declined significantly between 1940 and 1990." The sperm count of our species is in serious decline!   source 

Medical Research Council in Edinburgh, Scotland, thinks that the
decline in sperm is linked to some event that affects the
endocrine system, which governs the body's hormones. "

Are Human Sperm Counts Going Down?

The Demise of Human Sperm  *

... the average man has lost 53% of sperm production in the last 50 years.

Jouannet has become convinced.  And when he projects the decline into the future, he sees serious trouble for the human species.  He says gravely, at the present rate of decline, "It will take 70 or 80 years before it [sperm count] goes to zero."  below


Pesticides bioaccumulate?


Scientists for the first time have shown a link between levels of widely used agricultural pesticides in men's bodies and the number and quality of their sperm.

In a study out Wednesday, researchers found that men with higher levels of three pesticides widely used in the Midwest were more likely to have below-average semen quality and sperm counts than men with lower levels of the chemicals.

The scientists studied 50 men in rural Missouri and 36 men in Minneapolis. Their wives were patients at prenatal care clinics, so they were fertile. Based on semen samples, the men were divided into two groups: those with low sperm counts and quality and those with better semen quality.

"It's interesting that even within fertile men, there's a huge range," says lead author Shanna Swan, a family and community medicine professor at the University of Missouri-Columbia.

A Centers for Disease Control and Prevention lab measured levels of the byproducts of 15 different pesticides in urine samples from the men. Men with higher levels of alachlor, atrazine and diazinon were significantly more likely to have poorer sperm quality, the researchers report in the journal Environmental Health Perspectives. All three pesticides were more likely to be found in high levels in the Missouri men than in the Minneapolis men.

Only two of the Missouri men were farmers. Swan and her coauthors speculate that the men were exposed to the pesticides through drinking water. According to the authors, usual water treatment methods cannot remove them.

Ken Gordon, a spokesman for Syngenta, which makes atrazine, says there have been more than 800 studies of its health effects. "An overwhelming body of research supports the safety of atrazine for humans and the environment," Gordon says.

Rex Hess, a reproductive toxicologist at the University of Illinois-Urbana, praised the design and execution of Swan's study. The logical next step would be to test drinking water in Missouri for the pesticides, Hess says.

Reproductive biologist Sally Perreault of the Environmental Protection Agency says rodent studies suggest that even the highest pesticide levels found in Swan's subjects would have been too low to affect sperm quality. Still, Perreault says, the new study "really does raise a flag."

Our Stolen Future: Coverage in newspapers and newswires

CHEC Article List: News (Printer Friendly)

June 17, 2003 Study links pesticide exposure to low sperm counts and quality.  back up


These among the 101 chemicals to be checked by EPA for endocrine disruption 

& answer to the question, "What are Endocrine Disruptors?"

How to test water for these?


How work-place conditions, environmental toxicants and lifestyle affect male reproductive function. (eng; includes abstract) By Bonde JP, Int J Androl, 2002 Oct; Vol. 25 (5), pp. 262-8; PMID: 12270022

Linked Full TextLinked Full Text  
CitationCitation  Linked Full TextLinked Full Text  

Title: Occupational risks for male fertility: an analysis of patients attending a tertiary referral centre.
Author(s): Kenkel S; Rolf C; Nieschlag E
Author's Address: Institute of Reproductive Medicine of the University, Münster, Germany.
Source: International journal of andrology [Int J Androl] 2001 Dec; 24 (6), pp. 318-26.
Journal Article: Country of Publication: England NLM ID: 8000141 ISSN: 0105-6263 Subsets: IM
MeSH Terms: Occupational Diseases/*epidemiology
AdultGermany/epidemiologyHumanMaleReferral and ConsultationSemen
Entry Date(s): Date Created: 20011212 Date Completed: 20020201
Citation ID(s): PMID: 11737412 Medline UI: 21601390
Database: MEDLINE

Abstract:  The impact of environment and occupation on male fertility is still under debate. We investigated whether certain occupations may be over- or under-represented among men attending our infertility clinic in relation to the entire population of the area. Diagnoses and semen parameters of 2054 infertile men from the district of Münster were analysed retrospectively. The patients were categorized into 29 occupational groups. The relative size of each group was compared with that of the entire population in the district of Münster. Farmers were over-represented compared with the general population. Farmers and painters/varnishers showed a significantly higher proportion of reduced sperm counts [odds ratios (OR): 2.13 and 2.17, 95% confidence intervals: 1.18-3.88 and 1.02-4.65] and severely reduced sperm concentrations compared with the entire group of infertile men; in addition, significantly more farmers presented with a history of maldescended testes than other occupational groups (OR: 2.76 and 2.84; CI: 1.12-6.75 and 1.27-6.34). Metal workers/welders formed significantly higher proportions of patients with reduced sperm motility (OR: 5.99; CI: 1.38-26.00). The relatively poor semen parameters of the painters/varnishers could be caused by exposure to toxins. This may also apply to the farmers (fertilizers, herbicides); however, the elevated rate of maldescended testes suggests an effect of exposure during prenatal development or a genetic cause. The findings for metal workers/welders may be because of heat or toxins at the workplace. The study demonstrates that certain occupations are preferentially associated with male infertility. *

Semen quality in relation to biomarkers of pesticide exposure. (eng; includes abstract) By Swan SH, Study for Future Families Research Group, Environ Health Perspect, 2003 Sep; Vol. 111 (12), pp. 1478-84; PMID: 12948887

Linked Full TextLinked Full Text  
"Pesticides lower sperm levels, study finds,"   USA Today, June 18, 2003

Scientists for the first time have shown a link   ... pesticides ... in men's bodies and the number and quality of their sperm. 

"On-the-Job Exposures May Reduce Sperm Counts"

Safety & Health; March, 2001, Vol. 163 Issue 3, p64, 1/4p

Reports on studies on the impact of work exposure on sperm counts, as published in the October 2000 issue of the 'Journal of Occupational and Environmental Medicine.'  Finding that occupational exposure to radio frequency energy and pesticides may lead to reduced sperm counts and other effects on semen quality.

ISSN:  0891-1797

Male infertility increases over past 40 years
One-half of 1% of men were functionally sterile in 1938. Today it has reached between 8-12% (an over 15-fold increase). "Functionally sterile" is defined as sperm counts below 20 million per milliliter of semen. 

Note: A recent report attaining media attention states sperm count has not declined over the past 4 decades.  However, note how the study used the dates of 1951 for the 1st comparison study.  1951 was well after the introduction of large amounts of chemicals into society and was a year in which vehicle emissions contained both high levels of lead and large amounts of toxic hydrocarbon/solvent combustion products.   Also, by 1951, pesticide use was making its way into consumer use. 

Dr. Cecil Jacobson         -        Reproductive Genetics Center          -      Vienna, Virginia
#496 (05/30/96): Chemical Industry Strategies, Part 2

.                       January 18, 1996                        .

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This must be the year of the sperm.  The NEW YORKER magazine ran

a long story[1] January 15th called "Silent Sperm" --a wry

reference to Rachel Carson's SILENT SPRING, which made its debut

in the NEW YORKER 35 years ago.  "Silent Sperm" describes the 50%

loss in sperm count that has occurred in men worldwide during the

past 40 years. 
"Silent Sperm," The New Yorker, January 15, 1996: Increasing male infertility and its link to estrogenic chemicals in the environment, such as DDT, are fastidiously examined in this 12-page, no-nonsense article by Lawrence Wright. His is a ploddingly thorough discussion of male infertility and genital problems, as well as sexual irregularities among several animal species, including the Florida panther. "The most likely villains are chemicals in the environment which masquerade as estrogen, the female hormone," according to Niels Skakkebaek, one of the world's authorities on infertility. In addition to estrogenic chemicals, Wright raises the possibility that chemicals which block estrogen or androgen receptors, such as dioxin, may be "even more potent in their effect than environmental estrogens." He concludes that "the fecundity of our children and grandchildren is certainly in question. Myriad chemicals in the environment may affect our hormonal balance, in ways that are still poorly understood." Unfortunately, he adds, reports of falling sperm counts are under attack from many different sources. This controversy has only begun.
 Furthermore, the January issue of ESQUIRE

features an article on sperm loss,[2] titled "Downward Motility."
Downward motility: when it comes ot sperm, you're half the man your grandfather was.

Esquire; 1/1/1996; Pinchbeck, Daniel
The sperm count of humans and animals is declining each year, according to several scientific studies. Testosterone levels are also getting lower, and reproductive problems are on the rise. Lifestyle and environmental factors may be to blame.

As far as I know, the last time I set foot in New York Hospital was in June 1966, when I was born. My return trip, twenty-nine years later, involves my own reproduction: I am here to take a sperm test, an awkward, slightly shameful ritual that may soon become a very common practice among young men.

That's because something peculiar seems to be h...

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MOTHER JONES magazine[3] also began the new year with a sperm

story, titled "Down for the Count."  

Down for the count. (sperm counts)
Mother Jones; 1/1/1996; Castleman, Michael

Research shows that the human male sperm count has plunged significantly since the 1930's, with one Dutch study showing a 42%drop since 1940. This threat to human fertility has largely been ignored by the media. One possible cause is the increased exposure to chemical estrogens.

There I stood, almost 14 years ago, at a San Francisco airport counter, waiting for the agent to hand me my ticket. The "Today" show had arranged to fly me to New York to tell the world about a story I'd written for an early issue of Mother Jones concerning the 40 percent decline in men's sperm counts since the 1...

600 of 7333 Characters

And the nation's newspaper

of record, the NEW YORK TIMES, ran a 4-part, front-page series on

increasing infertility in the U.S. January 7-10.

By far the most interesting and informative of these articles are

by Lawrence Wright in the NEW YORKER and Daniel Pinchbeck in

ESQUIRE. Wright and Pinchbeck interviewed dozens of prominent

researchers in the field of endocrinology (hormones) and

reproductive health in the U.S., Britain and Europe, and their

articles offer new human perspectives on the scientific

information we have been presenting since 1991 (see REHW #263,

#264, #323, #343, #365, #372, #377, #432, #438, #446, #447, #448).
#449 (07/06/95): Corporate Behavior
#448 (06/29/95): Another Study Shows Sperm Loss
#447 (06/22/95): The Challenge of Our Age [Hormone Disrupters]
#446 (06/15/95): Our Future in Doubt [Hormone Disrupters]

Here are some viewpoints that we have not previously offered our

readers in our own coverage of this issue:

** Danish pediatric endocrinologist (hormone specialist) Niels E.

Skakkebaek says that, in the late 1980s, "We had also been

wondering why it was so difficult for sperm banks to establish a

core of donors. In some areas of Denmark, they were having to

recruit ten potential donors to find one with good semen


** So Skakkebaek in 1990 studied sperm quality in Danish men. He

started with men working in nonhazardous office jobs and laborers

who did not work directly with industrial chemicals or pesticides

--men thought to be healthy.  For decades it had been believed

that the average man produced about a hundred million sperm per

milliliter of semen, and of that about 20% was expected to be

immobile.  Skakkebaek reported that 84% of the Danish men he

studied had sperm quality below the standards set by the World

Health Organization. The men themselves seemed normal in every

other respect.[1,pg.43]

** On the basis of the world's medical literature, Skakkebaek

calculates that in 1940 the average sperm count was 113 million

per milliliter, and that 50 years later it had fallen to 66


** Still more serious is a three-fold increase in men whose sperm

count was below 20 million--the point at which their fertility

would be jeopardized.[1,pg.44]

** In the United States, just as in Denmark, the number of donors

with good-quality sperm has become distressingly low.  As early

as 1981, researchers at the Washington Fertility Study Center

reported that sperm count of their donors, who were largely

medical students, had suffered a steady decline over the previous

eight years.  The researchers worried that, if the decline

continued at the same rate, within the decade there would be no

potential donors who could meet the approved or recommended


** The fact is that the number of morphologically normal sperm

[meaning sperm with a normal shape] produced by the average man

has dropped below the level of those of a hamster, which has

testicles a fraction the size of a man's.[1,pg.44]

** In the United States, according to the National Center for

Health Statistics, the percentage of infertile couples has risen

from 14.4 in 1965 to 18.5 in 1995.  Infertility is defined as

failure to produce a child after a year of normal sex.[1,pg.44]

** There has been little published research comparing racial and

ethnic sperm counts, particularly in Africa and many Third World

countries. But the studies that we do have show low counts nearly

everywhere: the latest count in Nigeria is 64 million per

milliliter; in Pakistan, 79.5 million; in Germany, 78 million; in

Hong Kong, 62 million.[1,pgs.44-45]

** Pierre Jouannet, director of the Centre d'Etude et de

Conservation des Oeufs et du Sperme in Paris, simply did not

believe Skakkebaek's conclusions.  Jouannet had data on 1350

Parisian men, all of whom had fathered at least one child and

therefore were of proven fertility, so he analyzed them,

expecting to refute Skakkebaek's studies.  To his astonishment he

found that sperm counts in his group had dropped steadily at 2%

per year for the past 20 years; in 1973 the average count was 89

million per milliliter and in 1992 it was 60 million.[1,pg.45]

** The expected sperm count for a Parisian man born in 1945 was

102 million, whereas the count of those born in 1962 was exactly

half that number.[1,pg.45]

** Jouannet has become convinced.  And when he projects the

decline into the future, he sees serious trouble for the human

species.  He says gravely, at the present rate of decline, "It

will take 70 or 80 years before it [sperm count] goes to

zero."[1,pg.45]  [Difficulty conceiving occurs at 20 million or

less; sterility occurs at five million or less.]

** Stewart Irvine, a gynecologist at the Medical Research

Council's Reproductive Biology Unit in Edinburgh, Scotland,

studied sperm production of Scottish males.  Men born in the

1940s had an average sperm count of 128 million, whereas those

born in the second half of the 1960s averaged only 75 million--a

decline of over 40% in a single generation.

** Irvine told Lawrence Wright, "I had a colleague visiting from

Australia, and he had with him a laptop computer with lots of

data from infertile couples.  He said, 'I'm sure these sperm

count drops are rubbish.  I'm sure there are other explanations

for it.' And I said, 'Well, just take your data and plot it by

year of birth and see what you get.'  He got the same


** "Infertility is definitely going up," says Dr. Marc Goldstein,

director of the Center for Male Reproductive Medicine at New York

Hospital.  "I see it in my practice.  There is a decline in

fertility in men and an increase in infertility in older couples.

Studies show an increase in infertility from 11 percent to 16

percent in all married couples."  He believes part of it may be

life style: marijuana, cocaine, alcohol, and sexually transmitted

diseases can all reduce sperm counts.[2,pg.80]

** But wildlife do not smoke marijuana or drink alcohol and there

are numerous reports of reproductive problems caused by

chlorinated chemicals in wildlife.

** Niels Skakkebaek, the Danish researcher, believes it is

something more fundamental than life style.  Whatever is

happening to men, he believes, some part of it must take place

during the early stages of human development--in the womb or else

shortly after birth--because damage to the male urogenital system

is evident in certain very young patients.[1,pg.47]

** Likewise, Richard M. Sharpe, a research physiologist with the

Medical Research Council in Edinburgh, Scotland, thinks that the

decline in sperm is linked to some event that affects the

endocrine system, which governs the body's hormones.  This must

happen, he believes, either in the womb or shortly after birth.

"I have absolutely no doubt this is the most important time in

your life, certainly if you're a male," he says. "This is when

your sperm-producing capacity as an adult is settled once and for

all."[1,pg.48]  Changes in life style won't help men whose

sperm-producing capacity has been crippled at birth.

** In a series of experiments, Sharpe exposed pregnant rats to

"minute quantities" of DES and to other synthetic estrogens

[female sex hormones]; he showed a 5 to 15% decline in sperm

count in male offspring when they matured. [DES, or

diethylstilbestrol, is a synthetic female sex hormone that was

given medically to women in the U.S. in the 1950s and 1960s; many

of their male offspring have reduced sperm counts.][1,pg.48]

** Philippe Grandjean, a professor of environmental medicine at

Odense University in Denmark summarized the situation nicely in

an interview with Lawrence Wright: "We thought in the past that

these toxic substances would act on a target--an enzyme or DNA or

the cell membrane, or something like that.  But what these

endocrinologists have suggested to us is that industrial

chemicals can actually mimic hormones.  It looks as if the

receptors aren't very good at recognizing what's a hormone and

what's not a hormone--perhaps because they were never previously

challenged.  These receptors have been kept almost unchanged in

the mammalian world, because they worked.  They functioned very

well.  But in this century we have generated all these new

chemicals and injected them into the envi-ronment, and suddenly

the body is exposed to new substances that in some cases can

interact with that receptor.  The human species is totally

unprepared for this, because it has never happened before.  I

think the perspective is both very exciting and very, very


** Most--though not all--of the estrogen-mimicking chemicals

involve chlorine.

** If, as Theo Colborn theorizes, the number of chemicals that

can harm reproduction add up to hundreds, if not thousands, the

only way to regulate them all will be to "reverse the onus" that

now falls on individuals to prove they have been harmed by a

toxic substance.  "The responsibility should not be on the people

exposed to chemicals to prove they have been hurt," says David

LaRoche, the secretary of the International Joint Commission

(IJC).  "The responsibility should be on industry to prove that

chemicals cause no harm."[2,pg.84]

** "I have heard that the Chlorine Chemistry Council's budget is

around $100 million," Gordon Durnil told Daniel Pinchbeck.

Durnil is the former chairman of the IJC and author of THE MAKING


a lot of money.  You could use it to buy some research.  Why

don't they do some research to say what they are doing is safe?"

Durnil asks.[2,pg.84]

** Unfortunately, the truth about the sperm count is that it is

under attack from many different sources. Dioxin, for example, is

a chlorinated chemical that does not mimic hormones.  Yet it

diminishes sperm count in male animals.

** Earl Gray, a senior research biologist with U.S. Environmental

Protection Agency (EPA), testified before Congress in 1993 that,

"Our studies [in rats] show that a single dose of dioxin

administered during pregnancy permanently reduces sperm counts in

the males by about 60 per cent."[1,pg.53]

** "With sperm counts, I've been more impressed by the dioxins

and the PCBs than by the estrogens and anti-androgens," Gray

said. "We get surprising effects at relatively low


** "Probably half the jobs in the world are associated in some

way with chlorine," says Gordon Durnil. "As a society, we are

going to have to confront our dependence on this chemical."[2,pg.82]

                                                --Peter Montague


[1] Lawrence Wright, "Silent Sperm," NEW YORKER (January 15,

1996), pgs. 42-48, 50-53, 55.

[2] Daniel Pinchbeck, "Downward Motility," ESQUIRE (January

1996), pgs. 79-84.

[3] Michael Castleman, "Down for the Count," MOTHER JONES

(January/February 1996), pgs. 20-21.


Environmental Research Foundation provides this electronic

version of RACHEL'S ENVIRONMENT & HEALTH WEEKLY free of charge

                                        --Peter Montague, Editor
Diminished sperm count is not the only factor in male sterility. If sperm quality is compromised, higher sperm counts are needed for reproduction to take place. As sperm motility (the ability of the sperm to move) is impaired, the sperm may be unable to pass through the cervical mucous or penetrate the hard outer shell of the egg. When sperm motility is reduced, sperm become increasingly incapable of fertilizing the egg.

Abnormally shaped sperm also have difficulty fertilizing an egg. In one study, if 14% or more of sperm had round enlarged heads (indicating early unraveling of genetic material) the chances for pregnancy fell to about 20%. (2)

It appears increasingly certain that in today’s world both the quantity and quality of male human sperm are declining.  source


The pituitary-testicular axis in Klinefelter's syndrome and in oligo-azoospermic patients with and without deletions of the Y chromosome long arm. (eng; includes abstract) By Tomasi PA, Clin Endocrinol (Oxf), 2003 Aug; Vol. 59 (2), pp. 214-22; PMID: 12864799

Title: Identification of a Y chromosome haplogroup associated with reduced sperm counts.
Author(s): Krausz C; Quintana-Murci L; Rajpert-De Meyts E; Jørgensen N; Jobling MA; Rosser ZH; Skakkebaek NE; McElreavey K
Author's Address: Immunogénétique Humaine, INSERM E021, Institut Pasteur, Paris, France.
Source: Human molecular genetics [Hum Mol Genet] 2001 Sep 1; 10 (18), pp. 1873-7.
Journal Article: Country of Publication: England NLM ID: 9208958 ISSN: 0964-6906 Subsets: IM
MeSH Terms: Sperm Count*
Y Chromosome/*genetics
AllelesEvolution, MolecularFollicle Stimulating Hormone/bloodGenetic MarkersHumanInfertility, Male/geneticsInhibins/bloodLuteinizing Hormone/bloodMaleOligospermia/geneticsPhylogenyPolymorphism (Genetics)Semen/cytologySex Hormone-Binding Globulin/metabolismSupport, Non-U.S. Gov't
CAS Registry No.: 0 (Genetic Markers)
0 (Sex Hormone-Binding Globulin)
0 (inhibin B)
57285-09-3 (Inhibins)
9002-67-9 (Luteinizing Hormone)
9002-68-0 (Follicle Stimulating Hormone)
Revision Date: 20021101
Entry Date(s): Date Created: 20010913 Date Completed: 20011204
Citation ID(s): PMID: 11555623 Medline UI: 21439332
Persistent link to this record:
Database: MEDLINE

Abstract:  In man, infertility is associated with microdeletions of specific regions of the long arm of the Y chromosome. This indicates that factors encoded by the Y chromosome are necessary for spermatogenesis. However, the majority of men with either idiopathic azoospermia or oligozoospermia have grossly intact Y chromosomes and the underlying causes of their infertility are unknown. We hypothesized that some of these individuals may carry other rearrangements or sequence variants on the non-recombining region of the Y chromosome that may be associated with reduced spermatogenesis. To test this hypothesis, we typed the Y chromosome in a group of Danish men with known sperm counts and compared the haplotype distribution with that of a group of unselected Danish males. We found that one class of Y chromosome, referred to as haplogroup 26+, was significantly overrepresented (27.9%; P < 0.001) in the group of men with either idiopathic oligozoospermia (defined as <20 x 10(6 )sperm/ml) or azoospermia compared to the control Danish male population (4.6%). This study defines, for the first time, a class of Y chromosome that is at risk for infertility in a European population. This observation suggests that selection may be indeed active on the Y chromosome, at least in the Danish population, raising the possibility that it could alter the pattern of Y chromosome haplotype distribution in the general population.