An endocrine disruptor is an external substance or mixture that has an effect the functioning of the endocrine system. This can potentially lead to negative health effects in an organism or its offspring. These disruptors can be found in various sources, including natural substances, industrial chemicals, consumer products, pharmaceuticals, and pesticides. They can have estrogenic, anti-estrogenic, or anti-androgenic properties and can particularly impact ovarian development due to their influence on hormone regulation. [AI generated definition based on: Yen & Jaffe’s Reproductive Endocrinology (Sixth Edition), 2009]