These chemicals disrupt the normal hormonal messages that tell a body when and how to develop. However, more than a quarter-century later, chemicals may still be undermining our ability to reproduce, to learn and to think. The endocrine system is one the body's three integrating networks. It is made up of glands, hormones, and target cells that comprise a complex network of chemical signals and messages controlling many immediate and lifelong bodily responses and functions. In order to send messages, hormones lock into receptors and, like a key in a lock, send the required signal.
Hormones are very potent chemicals that operate at low concentrations.
This sensitivity allows for variations in offspring from the same genetic code. However, it also makes the endocrine system vulnerable to serious disruption if something interferes with normal hormone levels. Interference with hormone functions is particularly dangerous to developing embryos and newborn babies. Such interference may emerge later in life as lower sperm counts, cancers, miscarriages and tubal pregnancies, impaired learning ability, reduced immunities and behavioural disorders such as hyperactivity. Children are most vulnerable to the potential effects of hormone disrupting chemicals due to the high level of hormonal activity taking place during development.