Hormone systems disrupted
Our living environment contains substances that can damage these hormones or disrupt their function, explains Legler. 'Examples are pesticides, substances in plastics, packaging, medicines, and cosmetics and also industrial substances such as flame retardants. These are produced by the chemical industry for very different purposes but can have undesirable side effects for the endocrine systems of people, animals and the functioning of ecosystems. As a toxicologist, I investigate how the substances can disrupt the endocrine system.'
Concerned about nature
Juliette Legler grew up in Canada. She was always outside, busy with plants, bugs and birds in the garden. 'From a young age, I've always been concerned about ecology and the environment. In Canada, I was surrounded by endless nature, and I loved that. At high school, I studied ecology, and that subject thoroughly fascinated me. I had a eureka moment when I realised life was all about connections: between people and animals, between different animal species and between animals and their environment! It was fantastic to see how all of that fitted together. So once I had finished high school, I went to study environmental sciences. Not because my family wanted me to but because of my own interest in ecology and the environment.'
During her study, Legler did an internship in the Netherlands where she gained her first experience with laboratory research and in toxicology. 'I enjoyed that so much! Toxicology is about how poisonous substances affect people and the environment. This subject offered me a way to protect both. So back then, I decided I wanted to be both a researcher and a toxicologist.' Over the years, Legler's research has increasingly focused on human health. 'Some people no longer consider me to be an environmental toxicologist because I have stopped working on bugs in the soil. However, it is humans who need to be made aware of the effects of substances around us. I consider myself to be a bridge between environmental and human toxicology.'
After a successful scientific period at VU Amsterdam and Brunel University (London), Legler was appointed Professor of Toxicology at the Faculty of Veterinary Medicine in 2018. There she leads 'one of the best toxicology groups in the world'.