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Prenatal Origins of Endocrine Disruption

Critical Windows of Development


New! Critical Windows Learning Module

A tool for teaching endocrine disruption

to college students. Download here.

Critical Windows of Development is a timeline of how the human body develops in the womb, with animal research showing when low-dose exposure to endocrine disrupting chemicals during development results in altered health outcomes.

Human-made chemicals have become an accepted part of our world. They’re in what we eat, what we drink, what we touch, and what we breathe. In fact, they can be found in the umbilical cords of almost every baby born today.

Many of these chemicals have been recognized as ‘endocrine disruptors,’ which means they interfere with the communication system of glands, hormones and cellular receptors that control our body’s internal functions.

Low dose exposure to endocrine disruptors, once thought to be harmless, has been shown to have serious health effects in lab animals exposed in the womb and/or shortly after birth through their mother’s milk.

Effects found in animals occur at chemical doses comparable to concentrations regularly found in humans and may provide a clue to the many disorders that have dramatically and inexplicably increased since these chemicals became part and parcel of human existence.

Click here to View the Timeline, or choose from the menu to the right for more information.

CU Boulder, Department of Integrative Physiology endorses and supports this website.