Barbara Demeneix, Professor at the French National Museum of Natural History, is an internationally recognized expert on thyroid function and endocrine disruption. She is the work package leader of WP4 on identification of molecular initiating events in EDC-MixRisk project. Recently, she was interviewed for European Chemicals Agency’s newsletter on how chemicals can result in autism and IQ loss in developing children.

Endocrine disruptors are ubiquitous chemicals that interfere with body’s hormonal system, thereby producing harmful effects on human health including infertility, cancer and developmental disorders. These chemicals are released in our environment and can be found in daily products, such as in plastic bottles, toys, cosmetics, electronics, textile products and pesticides.

Exposure to these chemicals during foetal development poses a particular risk because the organ systems are still developing. Studies have shown that maternal levels of thyroid hormone during the first three months of pregnancy are determinant for the child’s brain development. Interference with the levels of maternal thyroid hormone will have a long-term impact on the formation and development of organs and neurons in the foetus. Many chemicals to which we are exposed can interfere with thyroid hormone signaling.

There has been a sharp increase in neurodevelopmental and metabolic diseases in modern western countries over the last decades. There is a biologically plausible mechanism between endocrine disruptors and their interference with thyroid hormone signaling: “Combining the facts that first, maternal hypothyroidism increases the risk of autism and second, that exposure to many chemicals reduces circulating thyroid hormones provides a strong case”, Professor Demeneix explains.

There is a need for rigourous testing as well as appropriate regulation of endocrine disrupting chemicals. The number of chemicals placed on the market is continuously increasing, so we are racing against time. However, you can try to limit your exposure to such chemicals. “Eating organic food can reduce your pesticide exposure. Also, you should air your home regularly and it is also very important to avoid smoking, either actively or passively, since this can alter thyroid hormone levels in early pregnancy,” Professor Demeneix advises. Further recommendations are developed in her latest book Toxic Cocktail.


Prof. Demeneix’s interview in ECHA’s Newsletter, People and Perspectives: How chemicals can result in autism and IQ loss in developing children, February 2018, Issue 1:

Her interview is also available on YouTube:

Toxic Cocktail: how chemical pollution is poisoning our brains has been published by Oxford University Press in 2017: