Endocrine Disruption

The thyroid system controls several developmental processes and participates in many physiological functions such as metabolic regulation, energy homeostasis, bone remodeling, reproduction, cardiac function and mental status in both children and adults. Thyroid function is regulated through the interaction between the hypothalamus, the pituitary and the thyroid. A large number of compounds such as pesticides, drugs, heavy metals, cosmetics, industrial chemicals and natural compounds have been shown to disrupt thyroid system homeostasis by acting on diverse regulation points of thyroid hormones metabolism, binding to thyroid receptors or altering gene transcription regulated through thyroid hormones among other mechanisms involved. There is special concern about thyroid disruptors because even slight variations in thyroid homeostasis may negatively affect human health, particularly during critical periods of vulnerability such as development and senescence or in sensitive population groups. This chapter focusses on known disrupting mechanisms and key factors influencing them.

Keywords: Endocrine disruption, thyroid hormones.