Wednesday, October 2, 2019
Pollution and Plunging Male Fertility :: Pollution Environment Environmental
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.
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