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Danish scientists discover abnormalities in the sperm of otherwise normal men. Sperm count studies from the 1930s reveal a fifty percent drop in sperm count over the past fifty years.
In the U.S. and U.K. testicular cancer has become the most common cancer in young men. Scientists suspect that sperm production is disturbed prenatally by abnormal, primitive-looking cells.
Testicular non-descent has doubled in the last 30-40 years. The urethral opening occurs on the dorsum of the penis rather than on the tip in cases of hyperspadias. Intersex conditions are also on the rise. What is affecting fetal development of the male reproductive system?
Importance of Prenatal Sertoli Cells
The number of Sertoli cells formed in the critical period of prenatal development fixes sperm output in the adult male. Abnormalities in prenatal Sertoli cell development may give rise to testicular cancer. Estrogen is thought to affect Sertoli cell development.
Prostate Cancer and Hermaphroditism
Diethylstilboestrol (DES) was prescribed as an anti-miscarriage drug in the 1940s and 1950s. Scientists discover that DES given to pregnant mice results in offspring with intersex conditions (hermaphroditism), hormone feminization, and prostate disease.
Estrogen Exposure and Diet
Scientists hunt for something occurring from pregnancy through childhood that explains the prevalence of estrogen in males. A modern diet of high fats and protein change the environment of the gut, thus allowing for the recycling of estrogens instead of eliminating them.
Compromised Endocrine System
Fish in a Great Lakes wildlife study exhibit cancer, de-masculinization, and hermaphroditism. Xenobiotic estrogens from pollutants interact with receptor molecules and turn on their biological effects to become hormone blocks, hormone accelerators, or metabolic transformers.
Contamination and Alligator Reproduction
In Florida's Lake Apopka, scientists discover alligator eggs contaminated with the chemical pollutant DDE, an endocrine disruptor. Surviving male alligators are emasculated and many cannot reproduce.
Sewage Effluence and Fish Gender Change
In the U.K., scientists discover that male fish exposed to sewage effluence develop hormonal changes and begin the process of gender change. Scientists come to a dead end in their search for the estrogen source in rivers.
Estrogenic Industrial Chemicals
In laboratory studies on breast cancer, scientists discover an estrogenic substance leaching from plastic tubing used in their experiments. The culprit, nonylphenol, is a widely used industrial chemical that was never supposed to be estrogenic.
Safety of Drinking Water
Nonylphenols present in high concentrations in rivers end up in drinking water. Water companies in the U.K. do not routinely monitor the presence of this compound, and further studies on estrogenic compounds drinking water must be carried out.
Estrogenic Compounds: Threat to Human Reproduction
The accumulation of estrogenic compounds released into the environment is a threat to male reproduction capabilities. Governmental legislation must include transgenerational health effects in their consideration of chemical releases into the environment.