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Theo Colborn, Ph.D., is an environmental-health analyst best known for her studies on the health effects of endocrine-disrupting chemicals (EDCs)—substances in the environment that mimic hormones and disrupt the hormonal processes in wildlife and humans. In 1991, she convened the interdisciplinary conference that produced the historic Wingspread Consensus Statement that alerted the world about endocrine disruption. She is coauthor of the book Our Stolen Future, which describes how chemical pollutants cause  birth defects, reproductive failures and sexual abnormalities.

Dr. Colborn is Founder and President of The Endocrine Disruption Exchange (TEDX), a nonprofit based in Paonia, Colorado. She has served on many advisory panels including the US Environmental Protection Agency (EPA) Science Advisory Board. At TEDX, she works to provide objective, technical information about endocrine disruption and related low-exposure hazards to academicians, policy makers, government employees, community-based and health support groups, public health authorities, physicians, the media and individuals. She appeared in the highly acclaimed independent documentaries, Emmy award-winning Split Estate and Gasland, which expose the health impacts of oil and gas drilling, and most recently Bag It, which discusses the repercussions of an overly plasticized world

EcoHearth: What are endocrine disruptors and how do we come into contact with them?

Theo Colborn: They are man-made chemicals that enter our bodies and interfere with our hormones—such as insulin, thyroxin, estrogen and testosterone. These natural hormones regulate such vital functions as body growth, response to stress, sexual development and behavior, the production and utilization of insulin, metabolism, intelligence and behavior, and the ability to reproduce.

Endocrine-disrupting chemicals are found in perfumes, cosmetics, sunscreens, men’s toiletries, cleaning compounds, pesticides, computers, cell phones, TVs and construction materials. Their presence is continually increasing inside our homes, cars and meeting places, etc., so that it is almost impossible to avoid them. Fortunately, the academic community is rapidly broadening its research to study how this constant, low-dose exposure may be affecting our health.

Phthalates, one type of ubiquitous EDC, are used to soften polyvinyl chloride (PVC) plastic, to make stuffed furniture, toys, cosmetics, shampoos, cream rinses and nail polish. They can enter our bodies through inhalation, food and skin. Many people think our skin is a barrier to these substances. But think about all the dermal patches we use to administer drugs. The skin is an effective conduit, and phthalates act as a delivery mechanism. For example, they are used in perfumes to hold the fragrance long after it is applied to the skin.

EH: When did endocrine disruptors begin to become more prevalent in the products we use and when did they begin to be seen as a hazard?

TC: After WWII, plastic gadgets, toys, automobiles, transportation and fire retardants were just a few of the materials that introduced endocrine disruptors into our everyday lives, air and waterways. Public and policymaker attention was raised by glaring industrial pollution of the Great Lakes in the 1960s and ‘70s. This spurred pollution-elimination legislation.

In 1976, the Toxic Substances Control Act gave EPA the authority to require reporting, testing and restrictions of chemical substances. But food, drugs, cosmetics and pesticides were not included.

EH: How have endocrine-disrupting chemicals wreaked havoc on ecosystems, and why haven’t federal agencies worked harder to protect environmental and public health?

TC: These petrochemical pollutants undermine normal gestational development in animals and humans. Government and academic studies have revealed that EDCs play a role in the development of systemic diseases such as diabetes, obesity and neurological conditions such as Alzheimer’s, Parkinson’s, ADHD and, in the last few months, strongly suggest autism.

The protection of public health suffered a setback when George W. Bush appointed John Graham as Administrator of the Office of Information and Regulatory Affairs (OIRA) in the White House Office of Management and Budget. He chose to protect America’s biggest polluters from whom he had accepted funding while working at the Harvard Center for Risk Analysis, which he founded and directed. During his tenure at OIRA, all funding for research into endocrine disruption and establishing environmental standards for endocrine disruptors was almost eliminated.

EH: Why are endocrine disruptors known as stealth chemicals and why is their timing so critical?

TC: They move on the air and in the water and are invisible in the body. There is no way doctors can see if their patients’ health concerns are chemically related. Billions of dollars are spent on treatment and cures for diseases because that is profitable, but prevention—which in the end could be extremely profitable—has been out of the picture. Exposure to endocrine disruptors before birth can cause irreversible lifetime disorders. The grandchildren of women who were exposed to EDCs like the pesticide DDT and the synthetic hormone DES—given to mothers to prevent miscarriage in the 1950s—are now suffering reproductive health problems, even though they and their own mothers were not exposed to these chemicals.

EH: The European Union (EU) has strengthened its policy on the registration, evaluation, authorization and restriction of chemicals (known by the acronym REACH). Why hasn’t the US taken strong action to ban harmful chemicals?

TC: In 2001, the Stockholm Convention on Persistent Organic Pollutants (POPs) was adopted internationally. It identified the 12 most bio-accumulative persistent chemicals that threaten human health and the environment to be banned. They included dioxins, PCBs, DDT and other widely used organochlorine pesticides. Even today, the US is one of just a few countries in the world that has not yet ratified the accord. This is called “passing off.” REACH is another pass-off. It has been pushed off the national government’s agenda to the top where it can sit and get a lot of attention, while the government does nothing about it. A recent example would be the position our government has taken with climate-change legislation.

EH: One event that brought endocrine disruption to the public eye was the discovery of bisexual bass in the Potomac River and a subsequent hearing on Capitol Hill. But the effect of EDCs on humans, particularly male reproductive systems, seems to be underreported.

TC: Yes, approximately 1 in 125 boys are born with hypospadias, a condition in which the urethra does not open where it should, at the tip of the penis. Over the past 20 years, US men have shown a 17% decrease in testosterone levels. Male fertility has declined. Fertility clinics have become a growing industry.

It is important to keep in mind that without properly functioning endocrine systems, species can go out of existence just like the fathead minnows that were exposed to endocrine disruptors in a test lake in Canada.

EH: Describe the Internet-based tool Critical Windows of Development that you and your team have created to show how EDCs interfere with normal human prenatal development.

TC: This tool took years to develop and was designed to help anyone understand what happens to a baby from conception to birth. First we show a picture (like a map) of what the construction of a baby looks like during the 38 weeks it spends in the womb. Then we show pictures using the results of studies that focused on prenatal exposure to specific chemicals in laboratory mice and superimpose that over what would be comparable to the same stage of development in humans. The idea was to produce a simple timeline about what is known about critical stages of development in all animal systems—the nervous, reproductive, endocrine and immune systems, and all the other organs.

Interference from EDCs hampers normal gene signals necessary for healthy development. Once these genes are programmed into the developing tissue of the unborn, they could, for example, determine how a teen or an adult would ordinarily respond to the normal chemical signals that control function as they mature. By clicking on a chemical such as bisphenol A, dioxin or phthalate, this tool illustrates how a low-dose exposure affects lab mice at a stage of gestation comparable to that of a human fetus. The map achieves a definite “wow effect” and gives people a visual tool that might make it possible to reduce exposure to these chemicals during pregnancy.

EH: What are some of the costs of endocrine disruptors to society and why is “inner-space” research—research on development in the womb—more important right now than outer-space research?

TC: We know that diseases of aging, such as Parkinson’s and Alzheimer’s, could be a result of prenatal exposure. A few years ago we were already spending $113 billion a year just providing insulin for diabetics. This does not include treatment of related conditions such as hypertension, obesity, and kidney and vascular problems. Many preterm births are related to endocrine disruption. Healthcare costs are breaking our economy. It breaks up the family when an adult stays home to care for a sick child or elder, and his or her partner works two jobs to make up for the lost income.

The family doctor often will not note hypospadias on the health record. Under our current system, the child would then become uninsurable. Some of the most important epidemiological studies have come from countries with free healthcare where there are no commercial insurance systems to discourage reporting.

EC: You have shown that the toxic chemicals used as lubricants in oil and gas drilling getting into the water and air are causing horrible health problems for people living near this activity.

TC: In speaking with individuals who have gotten sick working in the industry, I have learned of outrageous injustices. People who work in these extractive industries are required to sign a contract swearing that they must never talk about adverse health effects or what they see on the job. In our work we have discovered that fossil fuels are the single greatest source of endocrine-disrupting chemicals and throughout their production are increasingly destroying our life-support systems—air and water. The transition to renewable energy has never been more urgent.

[If you know someone who is deserving of an Eco Hero profile on EcoHearth.com, please contact us. – Ed.]

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