More and More Boys Born With Deformed Genitals -- What's to Blame?

By Joan Melcher, Miller-McCune.com. Posted October 23, 2009.

The term "endocrine disruptor" had not been coined when Rachel Carson was alive, but she was onto them.

Carson's groundbreaking 1962 book on the dangers of synthetic pesticides, Silent Spring, was prescient in many ways. She wrote about what she termed "insecticide storage:" "There are indications that these chemicals lodge in tissues concerned with the manufacture of germ cells as well as in the cells themselves. Accumulations of insecticides have been discovered in the sex organs of a variety of birds and mammals. ... Probably as an effect of such storage in the sex organs, atrophy of the testes has been observed in experimental mammals. Young rats exposed to methoxychlor had extraordinarily small testes."

Al Gore, who wrote in the forward to zoologist Theo Colborn's book on endocrine-disrupting compounds, Our Stolen Future, noted that Carson warned in one of her last speeches: "We are subjecting whole populations to exposure to chemicals, which animal experiments have proved to be extremely poisonous and, in many cases, cumulative in their effects. These exposures now begin at or before birth and — unless we change our methods — will continue through the lifetime of those now living. No one knows what the results will be because we have no previous experience to guide us."

Endocrine Disruptors

Earlier this month Miller-McCune discussed the observations and practical science of a woman, Judy Hoy, sounding an alarm in western Montana. A wildlife rehabilitator, Hoy has documented malformations of genitalia of local white-tailed deer over a 13-year period in the Bitterroot Valley. She suspects the changes are caused by endocrine-disrupting compounds (or EDCs), possibly from pesticides applied to potato fields just over the border in Idaho.

Montana officials so far have discounted her hypothesis, but scientific research around the world has made similar findings - undescended and abnormally small penises and testicles, low sperm counts, genitals placed forward on the body, confused gender - in test animals and in wild populations of birds, reptiles and wildlife.

What causes these changes remains contentious. Many scientists and public health advocates point to pesticides and other environmental pollutants while others, including industry, some government agencies and more scientists, say more study is needed.

While debating mutations in deer populations is one thing, finding those changes in boy babies takes the discussion to a new level.

Results of a study released in May 2009 by the British nongovernmental organization CHEMTrust show:

• as many as 1 in 17 boys in the United Kingdom have undescended testicles, a congenital birth defect;

• malformation of the penis (where the opening is not at the end) has increased in recent decades in several European countries, the United States, Australia and China;

• U.K. and French data show a decline in sperm count in young men as compared to their fathers; in some European countries, 1 in 5 young men has sperm counts so low that it is likely to affect their ability to father a child; and

• Testicular cancer is the most common cancer of young men, doubling in incidence in many Western countries every 25 years over the past 60 years.

The author of the report, Richard Sharpe, of the U.K.'s Medical Research Council wrote that many scientists are tying a lack of testosterone at critical times of fetal development to "testicular dysgenesis syndrome," encompassing defects of boys' genitals, low sperm counts and testicular cancer. He sees a link between hormone-disrupting chemicals and TDS, saying animal studies "have established beyond a doubt that certain hormone-disrupting chemicals, in particular testosterone-disrupting chemicals, can cause TDS-like disorders."

His meta-study might be one that Rick Becker, senior toxicologist with the American Chemical Council, would caution against. Becker asks that people not leap to conclusions after reading individual reports, but look to the World Health Organization for its synthesis of studies. However, the most recent WHO report on EDCs, "Global Assessment of the State of the Science of Endocrine Disruptors," was published in 2002.

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