Pollution and Plunging Male Fertility
Several reliable studies have confirmed that fertility among men has decreased as a result of pollution.
The average male ejaculation is about three milliliters. This amount of semen can contain between 20 million to 300 million sperm per milliliter semen. To determine the approximate number of sperm per milliliter of semen, technicians must place a drop of semen on a slide and, while looking through a microscope, they count the sperm within a certain sector. Men that have sperm counts below 20 million per milliliter are said to have reduced fertility and those whose counts fall below 5 million are considered sterile.
In 1974, C. M. Kinloch-Nelson and Raymond G. Bunge at the University of Iowa, studied the semen quality of men who had fathered two or more children and were about to undergo vasectomies. Of the 386 fertile men studied, 7% of them had sperm concentrations above 100 million per millimeter and the average concentration was 48 million. When they compared their findings to similar studies done in the thirties, they found that sperm counts had been decreasing for 50 years. "They discovered that among healthy adult males who were not being treated for infertility, the average sperm count had declined by about 40 percent, from 120 million sperm cells per milliliter of semen to about 70 million" (Big Drop 36).
In 1979, a professor at Florida State University, upon analyzing student semen samples discovered surprisingly low sperm counts and alarmingly high levels of toxic chemicals (including DDT and PLB's). "He suggested that environmental pollution might be causing the sperm decline" (Big Drop 36). The results of his findings triggered studies all over the world, showing counts in the range from 55 to 75 million and others showing numbers well above 100 million. Men exposed to high levels of toxic chemicals on the job were found to have semen containing pollutants. "Most scientists held to the view that changes in counting techniques were responsible for the reported dip" and . . . "after a few headlines, the sperm crisis became yesterday's news" (Big Drop 36).
In 1996, Niels E. Skakkebk, a Danish pediatric endocrinologist, began studying male infertility and growth disorders among children . He had been noticing numerous boys with testicles that had not descended and malformed genitals. A study done in 1984 examining 2,000 Danish school boys showed that 7% of them had one or both testicles still inside their bodies. Skakkebk then studied men working in non-hazardous office jobs, and men who did not work directly with pesticides or industrial chemicals. His study confirmed that, despite being normal in every other aspect, 84% of the men studied had sperm quality below the recommended standards set by the World Health Organization.
In 1992, Skakkebk and his Danish colleagues reviewed all of the published sperm count studies in the world. There were 61 total, dating back to 1938. Overall there were 15,000 men studied with no history of infertility. The survey showed an overall decline in world sperm counts. Skakkebk found that the quantity of semen produced in the average ejaculation had decreased and sperm counts had dropped from 113 per milliliter to 66 million the past 50 years.
When Skakkebk's findings became known, many researchers world wide began to publish new information about sperm counts. "Their studies 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" (Wright 4).
Some scientists were skeptical about Skakkebk's work, in particular Pierre Jouannet, a reproductive biologists who is the director of the Centre d'Etude et du Conservation des Oeufs et du sperme at the Hospital Cochin in Paris, and Dr. Stewart Irvine of the Medical Research Council's Reproductive Biology unit in Edinburgh. Jounnet and other French researchers examined 1,351 men, proven fertile, over the last 20 years. They were astonished to find that sperm concentrations had been decreasing at a rate of 2% a year, from 89 million in 1973 to 60 million in 1992. They also found the quality of the sperm had declined. Dr. Stewart Irvine had been conducting a study on Scottish males when Skakkebk results came out. Irvine found out that men born before 1959 had an average sperm count of 98 million. This decreased 20% by 1970 when sperm counts averaged 78 million per milliliter.
Skakkebk "sees the decline in sperm counts as only one part of a larger assault on the male reproductive organs, which is characterized by high rates of testicular cancer, and undescended testicles and hypospadias, a condition in which the urethral opening is on the underside of the penis, not on its tip" (Wright 5). He believes these diseases are developing in the early stages of development, because damage to the male urogenital system is evident in some very young patients . "In Skakkebk's opinion, the most likely [causes] are chemicals in the environment which masquerade as estrogen . . . These chemicals, which can have a temporary effect on adults, can cause permanent damage to boys whose sexual organs are not yet fully developed" (Wright 4).
Skakkebk revealed to Richard Sharpe, a research physiologist with the Medical Council of Edinburgh, his findings about the dramatic drop of sperm counts around the world. Sharpe began researching for sources of estrogen in the environment that cause disruption in the body's hormonal balance in ways such as Skakkebk had been observing. He learned that various synthetic estrogens are used as growth promoters in domestic animals. Sharpe believes that some of the that affect of something unknown on the endocrine system, which governs the body's hormones, are the reason for decline in sperm counts. He tested this theory by introducing minute quantities of DES (diethylstilloestrol known to cause undescended testicles and deformations of the penis) and other synthetic estrogens into the drinking water of rats that were pregnant. Male rats that were exposed via the pregnant mother grew up with their sperm production reduced by 5 to 15%. "[This] also advanced the theory that various industrial chemicals were behaving like synthetic estrogens, and that these chemicals might be responsible for the falling sperm count and the rise of disorders in the male reproductive tract" (Wright 6).
Estrogen is hard to avoid in our society. It is in birth control pills, deluxe shampoos, skin creams, and vaginal creams. To avoid stretch marks pregnant women rub estrogen lotions on their bellies. "Estrogen-like chemicals can pass undetected through a mother's body, creating havoc in the developing fetus" (Wright 7). It is also linked to increased rates of breast cancers, especially among men.
"There are isolated examples of other animals in nature that are experiencing reproductive problems similar to man's, including decreased fertility and sex reversals" (Wright 7). In Los Angeles sewer systems, DDT, an environmental estrogen, had been dumped for more than two decades and, as a result, female western gulls have become lesbians and have taken up nesting together because males have become disinterested in sex. In Lake Apopka, Florida, an alligator population has decreased drastically after a chemical mixing plant spilled a pesticide called dicofol (which contains DDT) into a lake. The female hatchling alligators have twice the normal estrogen levels, and ovaries in juveniles appear menopausal, males have registered no testosterone, and penis sizes are three-fourth to two-third of what they are supposed to be.
Though the affects of estrogen on animals have been proven, evidence has not yet confirmed the effects of estrogen on humans. There is a valid argument with almost irrefutable evidence that pollution effects fertility.
Several reliable studies have confirmed that fertility among men has decreased as a result of pollution.
The average male ejaculation is about three milliliters. This amount of semen can contain between 20 million to 300 million sperm per milliliter semen. To determine the approximate number of sperm per milliliter of semen, technicians must place a drop of semen on a slide and, while looking through a microscope, they count the sperm within a certain sector. Men that have sperm counts below 20 million per milliliter are said to have reduced fertility and those whose counts fall below 5 million are considered sterile.
In 1974, C. M. Kinloch-Nelson and Raymond G. Bunge at the University of Iowa, studied the semen quality of men who had fathered two or more children and were about to undergo vasectomies. Of the 386 fertile men studied, 7% of them had sperm concentrations above 100 million per millimeter and the average concentration was 48 million. When they compared their findings to similar studies done in the thirties, they found that sperm counts had been decreasing for 50 years. "They discovered that among healthy adult males who were not being treated for infertility, the average sperm count had declined by about 40 percent, from 120 million sperm cells per milliliter of semen to about 70 million" (Big Drop 36).
In 1979, a professor at Florida State University, upon analyzing student semen samples discovered surprisingly low sperm counts and alarmingly high levels of toxic chemicals (including DDT and PLB's). "He suggested that environmental pollution might be causing the sperm decline" (Big Drop 36). The results of his findings triggered studies all over the world, showing counts in the range from 55 to 75 million and others showing numbers well above 100 million. Men exposed to high levels of toxic chemicals on the job were found to have semen containing pollutants. "Most scientists held to the view that changes in counting techniques were responsible for the reported dip" and . . . "after a few headlines, the sperm crisis became yesterday's news" (Big Drop 36).
In 1996, Niels E. Skakkebk, a Danish pediatric endocrinologist, began studying male infertility and growth disorders among children . He had been noticing numerous boys with testicles that had not descended and malformed genitals. A study done in 1984 examining 2,000 Danish school boys showed that 7% of them had one or both testicles still inside their bodies. Skakkebk then studied men working in non-hazardous office jobs, and men who did not work directly with pesticides or industrial chemicals. His study confirmed that, despite being normal in every other aspect, 84% of the men studied had sperm quality below the recommended standards set by the World Health Organization.
In 1992, Skakkebk and his Danish colleagues reviewed all of the published sperm count studies in the world. There were 61 total, dating back to 1938. Overall there were 15,000 men studied with no history of infertility. The survey showed an overall decline in world sperm counts. Skakkebk found that the quantity of semen produced in the average ejaculation had decreased and sperm counts had dropped from 113 per milliliter to 66 million the past 50 years.
When Skakkebk's findings became known, many researchers world wide began to publish new information about sperm counts. "Their studies 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" (Wright 4).
Some scientists were skeptical about Skakkebk's work, in particular Pierre Jouannet, a reproductive biologists who is the director of the Centre d'Etude et du Conservation des Oeufs et du sperme at the Hospital Cochin in Paris, and Dr. Stewart Irvine of the Medical Research Council's Reproductive Biology unit in Edinburgh. Jounnet and other French researchers examined 1,351 men, proven fertile, over the last 20 years. They were astonished to find that sperm concentrations had been decreasing at a rate of 2% a year, from 89 million in 1973 to 60 million in 1992. They also found the quality of the sperm had declined. Dr. Stewart Irvine had been conducting a study on Scottish males when Skakkebk results came out. Irvine found out that men born before 1959 had an average sperm count of 98 million. This decreased 20% by 1970 when sperm counts averaged 78 million per milliliter.
Skakkebk "sees the decline in sperm counts as only one part of a larger assault on the male reproductive organs, which is characterized by high rates of testicular cancer, and undescended testicles and hypospadias, a condition in which the urethral opening is on the underside of the penis, not on its tip" (Wright 5). He believes these diseases are developing in the early stages of development, because damage to the male urogenital system is evident in some very young patients . "In Skakkebk's opinion, the most likely [causes] are chemicals in the environment which masquerade as estrogen . . . These chemicals, which can have a temporary effect on adults, can cause permanent damage to boys whose sexual organs are not yet fully developed" (Wright 4).
Skakkebk revealed to Richard Sharpe, a research physiologist with the Medical Council of Edinburgh, his findings about the dramatic drop of sperm counts around the world. Sharpe began researching for sources of estrogen in the environment that cause disruption in the body's hormonal balance in ways such as Skakkebk had been observing. He learned that various synthetic estrogens are used as growth promoters in domestic animals. Sharpe believes that some of the that affect of something unknown on the endocrine system, which governs the body's hormones, are the reason for decline in sperm counts. He tested this theory by introducing minute quantities of DES (diethylstilloestrol known to cause undescended testicles and deformations of the penis) and other synthetic estrogens into the drinking water of rats that were pregnant. Male rats that were exposed via the pregnant mother grew up with their sperm production reduced by 5 to 15%. "[This] also advanced the theory that various industrial chemicals were behaving like synthetic estrogens, and that these chemicals might be responsible for the falling sperm count and the rise of disorders in the male reproductive tract" (Wright 6).
Estrogen is hard to avoid in our society. It is in birth control pills, deluxe shampoos, skin creams, and vaginal creams. To avoid stretch marks pregnant women rub estrogen lotions on their bellies. "Estrogen-like chemicals can pass undetected through a mother's body, creating havoc in the developing fetus" (Wright 7). It is also linked to increased rates of breast cancers, especially among men.
"There are isolated examples of other animals in nature that are experiencing reproductive problems similar to man's, including decreased fertility and sex reversals" (Wright 7). In Los Angeles sewer systems, DDT, an environmental estrogen, had been dumped for more than two decades and, as a result, female western gulls have become lesbians and have taken up nesting together because males have become disinterested in sex. In Lake Apopka, Florida, an alligator population has decreased drastically after a chemical mixing plant spilled a pesticide called dicofol (which contains DDT) into a lake. The female hatchling alligators have twice the normal estrogen levels, and ovaries in juveniles appear menopausal, males have registered no testosterone, and penis sizes are three-fourth to two-third of what they are supposed to be.
Though the affects of estrogen on animals have been proven, evidence has not yet confirmed the effects of estrogen on humans. There is a valid argument with almost irrefutable evidence that pollution effects fertility.
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