Theo Colborn: a pioneer in identifying the problems caused by endocrine disrupting chemicals

On International Women’s Day, ChemTrust wanted to highlight the work of one woman in particular who had a significant impact on the field of endocrine disrupting chemicals, Dr Theo Colborn (1927-2014)

A trained pharmacist, Theo Colborn had an interest in wildlife from an early age. After completing her Master’s degree in science in 1981, she was awarded a PhD in Zoology in 1985 at the age of 58. Colborn undertook research on contaminants in the Great Lakes on the Canada-US border, and it was this research that demonstrated how endocrine disrupting chemicals were entering the environment and altering the development of wildlife. She co-authored the book ‘Our Stolen Future’, and in 2003 founded The Endocrine Disruption Exchange (TEDX) in the US, a non-profit organisation which aims to reduce the production and use of hormone disrupting chemicals.

ChemTrust sat down with co-founder of CHEM Trust, Elizabeth Salter Green, to talk about the impact that Theo had on the field. Elizabeth previously worked as Director of the WWF-UK Toxics Programme, and has also worked for WWF’s European Policy Office, and for WWF International. Prior to WWF she worked for several years as a marine biologist, and co-authored the book “The Toxic Consumer”.

When did you first hear about Theo’s work?

I first met her when she came to the UK for the launch of her book, ‘Our Stolen Future’ in 1996. I was lucky enough to work with her on European policy on endocrine disrupting chemicals. But I had heard of her before that, as I was working for WWF-UK in the marine programme, and she was working for WWF’s US office.

What contribution did Theo make to the field of endocrine-disrupting chemicals?

Theo Colborn figured out that chemicals could disrupt our development. She was working in the Great Lakes on the Canada-US border in the 80s and could see that the populations of top predators were decreasing. She worked out – of course with the help of colleagues – that once these persistent chemicals were in the mother’s bloodstream they could be passed across to the child, be it an egg or a foetus developing in-utero. She could see that these chemicals had the ability to look like hormones and that they were disrupting the offspring’s development before they were even born. They were causing fertility problems in mammals, raptors’ shells to be too thin, and that was why the populations of top predators were decreasing. In 1991, she brought together 21 scientists from across the world to discuss hormone disrupting chemicals in the environment.

 Were there others working on similar research at the same time?

There were other people looking at chemicals and their impacts on wildlife and humans, but they were not able to work out the mechanism of the chemicals as hormone disruptors. They didn’t use the term endocrine disruptor until Theo had, and then applied the term to their own work. She absolutely led the way.

 What was the impact of her work on future research into endocrine disruptors?

She, with that group of scientists, coined the term ‘endocrine disruptor’, and it was used in all the scientific literature. In 1996, she wrote ‘Our Stolen Future’, which explained how these chemicals could be bad for not only the wildlife that she had studied, but for humans too. I remember her coming to the UK for the book launch, and she and WWF got such bad press for scaremongering. But, by the early 2000s the EU was spending €200 million on endocrine disrupting chemicals research programmes. We had gone from being vilified in 1996, to be the cause of hundreds of millions of euros being spent on research because they knew that Theo’s work was right.

 Was there any impact on policy or chemical regulation?

When Theo came to the UK in 1996, she said these endocrine disrupting chemicals are a problem. So, WWF wrote to the European Commission and told them that they are overlooking this whole group of harmful chemicals in their chemicals legislation, but we were told that nothing was going to be done. So, with Theo’s help, we got an Own Initiative report written in the European Parliament. An Own Initiative report is used if an issue is felt to be really important, but you can’t get leverage with the Commission. In this case, we were fortunate that Kirsten Jensen from the Environment Committee took the leadership in drafting  an Own Initiative report on endocrine disrupting chemicals report in 1998.  Following this report, the Commission had to do something, and that was then when they started to produce a strategy on endocrine disrupting chemicals. It is thanks to Theo Colborn, WWF and the other NGOs, that endocrine disrupting chemicals were put  on the agenda and also into REACH, which is what we use today to regulate harmful chemicals.

 What impact has Theo’s work had globally?

When she brought these scientists together in 1991 they were from all around the world, so it was truly a global group, and so her message had a global reach. There was upset amongst chemical companies and documentaries made all around the world. While she had a global impact, the only part of the world that made formal legislation on endocrine disrupting chemicals was the EU.

 What influence has Theo’s work, or working alongside her, had on your own career?

She has definitely been the inspiration for my life’s work. I personally felt, the way that she did, that unless we get on top of these endocrine disrupting chemicals we were going to undermine the wellbeing of future generations. And then it was almost a perfect storm. Theo was undertaking the research in the US, I was in the UK and understood the science and policy, WWF was the world’s largest environmental organisation, and the European Union was producing environmental legislation to try and protect human health and the environment. We eventually got the EU to include endocrine disrupting properties as a criterion for managing chemicals. That is thanks to Theo, and that is all that my life’s work has been about.

 How is Theo an inspiration for others?

One of the things about Theo is that she was quite softly spoken, she didn’t have a massive ego, she just knew her science was right. She was a woman and most of her adversaries were men in grey suits working for big chemical companies, and she had an enormous adversary in that. I felt that it was one woman espousing the science, with the whole of the chemical industry wanting to shoot her down. But she would not be put off by others, she just kept going because she knew the science was right.

 Also, she had come to this quite late in life. It wasn’t until she was in her 50s, 60s, 70s, that she produced this new hypothesis of hormone disruptors. So, I suppose that says to me, you might have had a career, or children, and be wondering what you can achieve now. Well, Theo started her whole career on endocrine disrupting chemicals in her 50s, and look at the impact that her work has had.

Written by Eleanor Hawke on March 7, 2019.
Reference. Image credit wikimedia.

Twenty-Five Years of Endocrine Disruption Science: Remembering Theo Colborn


For nearly 30 years, Dr. Theo Colborn (1927–2014) dedicated herself to studying the harmful effects of endocrine-disrupting chemicals on wildlife, humans, and the environment. More recently, she extended this effort to address the health impacts of unconventional oil and gas development. Colborn was a visionary leader who excelled at synthesizing scientific findings across disciplines. Using her unique insights and strong moral convictions, she changed the face of toxicological research, influenced chemical regulatory policy, and educated the public. In 2003, Colborn started a nonprofit organization—The Endocrine Disruption Exchange (TEDX). As we celebrate the 25th anniversary of endocrine disruption science, TEDX continues her legacy of analyzing the extensive body of environmental health research and developing unique educational resources to support public policy and education. Among other tools, TEDX currently uses the systematic review framework developed by the National Toxicology Program at the National Institute of Environmental Health Sciences, to answer research questions of pressing concern. In this article, we pay homage to the tenacious woman and the exemplary contribution she made to the field of environmental health. Recommendations for the future of the field are drawn from her wisdom.

Author: DES Daughter

Activist, blogger and social media addict committed to shedding light on a global health scandal and dedicated to raise DES awareness.

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