This guest essay comes from Theo Colborn, an environmental health analyst, professor of zoology at the University of Florida, Gainesville, and president of The Endocrine Disruption Exchange (TEDX). She’s one of the experts featured in Leonardo DiCaprio‘s new eco-documentary The 11th Hour, which opens in L.A. and New York on Aug. 17 and in other spots around North America on Aug. 24.

What a crazy world we live in when almost everyone knows what the acronym ED stands for. Millions of dollars have been poured into creating awareness of ED, erectile dysfunction, because it is profitable. This 21st-century sales-pitch strategy — “disease mongering” — has proven to be good for the bottom line. The irony of all this is that there is another ED out there into which millions have also been poured — to keep it a secret. That ED is endocrine disruption, and if the public were to learn about it, bottom lines could shrink instead of grow.

Endocrine disruption should be right at the top of the list of most critical technological disasters facing the world today, up with climate change. With little notice, vast volumes and combinations of synthetic chemicals have settled in every environment in the world, including the womb environment. Synthetic chemicals at very low concentrations in the womb change how genes are programmed, cells develop, tissues form, and organs function, and thus undermine the potential and survival of developing animals, including humans. The chemicals threatening the integrity of future generations are derived from the processing of crude oil and natural gas, the same processes that are driving climate change. This is an integral part of the climate change story.

These chemicals, called endocrine disruptors, are in products that have become an integral part of our global lifestyle and economy. And in order for the products to be sold, the public must believe they are safe. Adding fuel to corporate denial is the unwillingness by anyone to accept the fact that every woman — yes, every woman — is walking around during her reproductive years with a mixture of chemicals in her body that cannot only change her physiology and how she functions, but also can start a chain of events that can change how her unborn child will be constructed, function, and mature throughout its lifetime. It is a transgenerational concept too preposterous for most people to accept. They would rather forget it. Besides, what can they do about it?

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The emergence of the endocrine disruption discipline stems from years of research around the Great Lakes, where it was discovered that wildlife and human mothers were transferring synthetic chemicals to their offspring through the egg or the womb and undermining their youngsters’ health and chances for survival. The anomalies in their offspring were the result of synthetic chemicals that caused disturbances of the endocrine system, which controls development and function — and the perpetuation of all species[1].

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The term “endocrine disruption” was coined in 1991[2], and acceptance of the concept caught on rapidly among academicians and those concerned about the human condition. As scientific evidence amassed about the diverse effects of endocrine disruption and what those effects reflected at the population level, so did efforts increase to deny the evidence and marginalize the effects on human health, by those who benefit economically from the production and use of endocrine disruptors.

Endocrine disruptors not only pose a threat to our ability to reproduce — they also pose a threat to the quality of the individuals we are able to produce. Fewer and fewer children will be blessed with the birthright to reach their fullest potential. Statistics today warn us that, as we move into the 21st century, we are becoming a caretaker society where already too many children need lifetime medication and/or care from the day they are born.

Think about this. The American Diabetes Association points out that the incidence of diabetes increased by 14 percent between 2003 and 2006, and if the trend continues, “one in three Americans, and one in two minorities, born in 2007 will develop diabetes in their lifetime[3]. The Centers for Disease Control and Prevention reported that 1 in 166 children born has an autism spectrum disorder, and among boys the odds are 1 in 89[4]. And one in 125 boys is born with hypospadias[5], a condition where the urethra does not open at the end of the penis. The Harvard School of Public Health estimates that globally, “One out of every six children has a developmental disability, usually involving the nervous system”[6]. Danish doctors report a widespread condition in the northern hemisphere, described as the male dysgenesis syndrome, that can be traced back to damage in the womb[7]. The syndrome includes undescended testicles, hypospadias, early onset of testicular cancer, reduced sperm quantity and quality, and impaired fertility. The prestigious journal of The Endocrine Society published the results of a study that showed an age-independent decline in testosterone levels in U.S. men over the past 20 years[8].

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And most disturbing is the report in the journal of the National Institute of Environmental Health, revealing a correlation between the concentration of a widely used plastic compound in the urine of women during their pregnancy and an alteration in the development of their sons’ external genitalia. As the concentrations of the plastic increased, the babies experienced a shortening of the distance between the anal opening and the base of their penis, and reduced penis volume and length. Based on these two measurements, they had a greater tendency for undescended testicles[9]. These are only some of the disorders that can be of fetal origin that are common in the human population today; only two generations ago, they were rare. Do you suppose that industry knows something they have not been sharing with the public?

Suddenly we are told that almost 50 percent of the U.S. population is going to develop diabetes. Does no one realize that the pancreas is an endocrine gland, and that it produces a hormone, insulin; and that perhaps diabetes is one of those disorders that is imprinted before birth — or even triggered later in life — by one or many of the widely dispersed chemicals that interfere with glucose metabolism and insulin?

Why has the government almost completely phased out programs devoted to understanding endocrine disruption? Why was the only laboratory dedicated to endocrine disruption research for over 30 years told to shut down within a month? Why was funding for the National Children’s Health Study suddenly canceled after six years and $60 million invested in building the infrastructure, just at the stage where mothers were going to be enrolled?

There may be many reasons why the government took those steps, but one thing is apparent — toxicology has failed miserably. Quite frankly, I am willing to say that toxicology has failed by design to provide the technology needed to detect endocrine-disrupting chemicals. It is interesting to note that it was toxicologists, corporations, and trade associations over 40 years ago that blatantly attempted to undermine Rachel Carson and her message. Carson revealed in Silent Spring that she was on the verge of breaking the secret of endocrine disruption wide open. Unfortunately, when the government moved forward to develop screens and assays to detect endocrine disruptors, it turned to the toxicologists to solve the problem, not those who developed the laboratory techniques to discover endocrine disruptors.

The list of chemicals that have been identified as endocrine disruptors is mushrooming, as independent academicians around the world have begun to look at the safety of chemicals from an entirely new angle. Most of them are not toxicologists. They have demonstrated that hundreds of widely disseminated industrial chemicals and pesticides alter the homeostasis of the endocrine system. The truth is that the protocols to test chemicals for their safety and the regulations to assure product safety failed to prevent the use of these chemicals, which we commingle with continuously in our homes, schools, places of business, and the outdoors.

Until decision makers understand this, there is no way to reverse the increased dusting of the Earth with more synthetic chemicals. It is late, but there is still time to go back and start over. The new agenda should be driven by prevention, free of a bottom line. Governments must give those trained in endocrinology, embryology, developmental biology, epidemiology, biochemistry, demography, medicine, and other fields the resources and the infrastructure to collaborate and produce. And in the decade ahead, the political environment should allow scientists to step out of their traditional roles and share with policy makers the implications of their findings without being frowned upon by their peers or vested interests.

Humankind is approaching the fourth generation of individuals born with the products of modern chemistry in their bodies. At the same time, humankind is facing a pandemic of endocrine-related disorders that can seriously alter our quality of life, the global economy, and worldwide stability. Scientists have demonstrated that some synthetic chemicals can cause the same disorders that have rapidly become major public health concerns. Society can choose to continue to ignore this problem it created, or it can bite the bullet and start over — by placing the problem in the hands of those who understand endocrine disruption and have no vested interest other than that of the well-being of future generations.


[1] Beland P, et al. 1989. Report of Work Group on Environmental and Wildlife Toxicology. Pl 79-107 In: Report to the Canada/US International Joint Commission Science Advisory Board: Proceedings from a Workshop to Evaluate Risks to Human Health Associated with Exposure to Toxic Chemicals in the Great Lakes Ecosystem. Niagara-on-the-lake, Ontario, April 16-18, 1989.

[2] Bern HA, et al. 1992. Statement from the Wingspread Work Session on Chemically Induced Alterations in Sexual Development. Pp. 1-8 In: Colborn, T.; Clement, C, eds. Chemically Induced Alterations in Sexual and Functional Development: The Wildlife Human Connection. Princeton, N.J., 403 pp.

[3] American Diabetes Association. American Diabetes Association Urges Congress to Increase CDC Diabetes Prevention Funding by $20.8 Million: One Dollar for Every American with Diabetes. Available at: Accessed January 22, 2007.

[4] Centers for Disease Control and Prevention. How common are Autism Spectrum Disorders (ASD)? Available at: Accessed January 10, 2007.

[5] Paulozzi, LJ, et al. 1997. Hypospadias trend in two US surveillance systems. Pediatrics 100(5) 831-834.

[6] Datz, T. 2006 Nov 7. A Silent Pandemic: Industrial Chemicals are Impairing the Brain Development of Children Worldwide. HSPH press release. Available at:; Accessed January 22, 2007.

[7] Skakkebaek, N.E. et al. 2006. Is human fecundity declining? International Journal of Andrology 29(1):2-11.

[8] Travison TG, et al. 2007. A population level decline in serum testosterone levels in American men. Journal of Clinical Endocrinology and Metabolism 92(1): 196-292.

[9] Swan SH et al. 2005. Decrease in anogenital distance among male infants with prenatal phthalate exposure. Environmental Health Perspectives 113(8): 1056-1061.