Theo Colburn

Theo Colburn is a leading world expert on endocrine disruption from Colorado. While working as a pharmacist and sheep rancher on her western Colorado property with her husband, she became concerned about local coal and mineral mining pollution and its threat to her environment and health. This led to her attaining her Ph.D. in Zoology in the 1980s at the age of 58. In her research, she discovered that a great number of predators in the Great Lakes region were suffering from reproductive disorders. The commonality between them was that they were all contaminated with abnormal, industrialized levels of estrogen. She ascertained that industrial pollution had caused disruptions to their endocrine systems.

The endocrine system, which regulates bodily hormones (like estrogen), affects bodily functions including body growth, stress response, sexual development, insulin capability, metabolism, intelligence, and behavior. Abnormalities in the endocrine system have been linked to major modern medical problems such as ADHD, diabetes, obesity, testicular cancer, endometriosis, autism, and fertility difficulties. Changes often accumulate slowly, however, or demonstrate their effects later than exposure in the life cycle, unless the organism is exposed to toxins while developing in the womb. When Theo was first exploring this phenomenon, little was known about pre-natal development and factors that influence the endocrine system. However, she says “the evidence is now overwhelming that prenatal exposure can lead to irreversible disorders”.

She notes that we are currently in the 4th generation of endocrine-disrupted individuals since major chemical manufacturers began including fossil-fuel derived chemicals in the majority of consumer and non-consumer products. The 20th century (and now 21st) has been an experiment in determining the synthetic world’s consequences for the living world. Our children’s toys, cosmetics, cleaning products, household items (and even food) are all greatly derived in some way from synthetic chemicals and processes. As Theo says, “we live in a plastic world”. As a result, 1 in 3 Americans born today will develop diabetes in their lifetime and 1 in 150 children born today has an autism spectrum disorder (including 1 in 59 boys).

We are neutering the population—we are making females more masculine and we are making males more feminine. Up until day 56 from the day of conception you can’t tell the sex of the fetus. The tissue that’s there is going to eventually produce testicles or ovaries. Now, it takes just a slight tweak of a hormone to make it grow into a male tissue and become a testicle; a tweak in the other direction and it will become female tissue. What we’re finding in fish and birds and even mammals now are ovotestes, or testes that have ovarian tissue in them. -Theo Colburn

Endocrine disruptors, however, are called “stealth chemicals” because pinpointing their linkages often goes under the radar of major medical practitioners. The chemicals have no regulation for their endocrine-related health effects and are so entrenched in politics that they have a lot of industry-funded researchers disputing their harm. In speaking out against these toxins, Theo Colburn has made a lot of enemies. She believes though that industry has a “moral responsibility” to put more money into legitimately researching how these common chemicals affect human and wildlife health. After all, she says, “they want a healthy population to which they can sell their products”…

I am praying that we can find one or two really conscionable corporate executives who are willing to dedicate the rest of their lives to future generations. This is our only hope. This is why I’m doing this work. I pray I live long enough so that I can needle enough people to do it. -Theo Colburn

Theo’s vision is for human health to be the bottom line in manufacturing decisions. She wants corporate interest to be divested of government decision-making and for our economy to find and use alternatives to fossil fuels. She believes that endocrine-disrupting chemicals are an urgent risk to our society and that vast numbers of widely dispersed chemicals, derived from fossil fuels, could pose a more imminent threat than climate change to the survival of humans and all living organisms on earth. To increase education on the issue, in 1996 Theo published the book Our Stolen Future: Are We Threatening Our Fertility, Intelligence and Survival? A Scientific Detective Study. In 2003, she founded The Endocrine Disruption Exchange, a “non-profit dedicated to compiling and disseminating the scientific evidence on [endocrine disruptors]”.

Theo has also become a leading expert on the process of fracking and its resulting health impacts. She found that 43% of fracking chemicals in Colorado (and 37% overall in the U.S.) are endocrine disruptors. 75% of the natural gas chemicals she studied could affect the eyes, skin, respiratory and gastrointestinal systems; 40-50% could affect the brain, nervous, immune and cardiovascular systems; and 25% could cause cancer. Theo has made a really thorough video called “What You Need to Know about Natural Gas Production” that is posted on The Endocrine Disruption Exchange website. I also recommend checking our her YouTube video “The Male Predicament” which succinctly explains endocrine disruption in more detail:

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