Recent studies show males of many species, not only humans, are not doing well in the polutant battle: "The environmental impacts of phthalates in plastic inhibit testosterone production and possibly may cause irregular genital development. Brominated flame-retardants may block the thyroid hormone critical to proper development of both the testes and the brain. University of Missouri professor, Dr. vom Saal, said, ‘This mishmash of synthetic hormones - leading to too much estrogen and too little testosterone and thyroid hormone - is making a mess of sexual development in males.’ He conducted studies relative to sperm health comparing various geographic locations. A markedly lower sperm count in males from farming areas verses urban areas suggests pesticides are to blame."
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