What Are Endocrine Disrupting Chemicals?
What are endocrine disrupting chemicals (abbreviated EDCs)? Never heard of them before? If you care about your health (and the health of your (unborn) children) then you owe it to yourself to read this blog post about EDCs, where we get exposed and how they affect our health.
Over the last two decade there has been mounting scientific evidence that EDCs pose a severe threat to the health of humans and wildlife (breaking up the details below). And nearly 800 – yes, eight-hundred! – chemicals are known or suspected to pose endocrine disruption and only a fraction of these have been under scrutiny and studied.
Before I started researching the topic, I was under the naive impression that the chemicals used in our everyday lives surely must have been studied and found safe for use. That’s, however, not the case.
Okay, That’s Disturbing. But Why Should We Care?
Because it affects EVERYONE (unlike different medical conditions such as rosacea or allergies, that only affect a minority of the population). Every living organism on this planet is affected – it’s that simple.
The route into humans:
EDC’s are in the food we eat, absorbed via our skin and in the air we breathe. Read more about where we get exposed to EDCs in my second blog post on this topic What Are Endocrine Disrupting Chemicals? Part Two, that will be up next week.
On that uplifting note (of biblical proportions) let’s get the facts straight.
The current definition was established in 2002 by WHO in the International Programme on Chemical Safety :
“An endocrine disrupter is an exogenous substance or mixture that alters function(s) of the endocrine system and consequently causes adverse health effects in an intact organism, or its progeny, or (sub)populations.”
“A potential endocrine disruptor is an exogenous substance or mixture that possesses properties that might be expected to lead to endocrine disruption in an intact organism, or its progeny, or (sub)populations.”
How do EDCs affect us?
EDCs either mimic, counteract or compete with our own hormones and disrupt the normal function of our complex endocrine (hormonal) system. This can lead to various chronic auto-immune disorders, cancers and compromised fertility, to name a few. To understand how and what EDCs actually do in our body, let’s go back and refresh what we all clearly remember from biology class about the actions of our hormones.
What Are Hormones?
Hormones are tiny molecules that are produced in specific endocrine glands and tissues in different places in our body. They are transported via the blood to specific target cells (cells that are meant to react to the hormone), located in a specific target organ. Hormones are vital and conduct major physiological processes in your body.
The Human Endocrine System. Shown are our endocrine glands and the hormones they produce. Figure from reference 2
How Do Hormones Work?
When the hormone reaches the target organ it binds to specific receptors on the surface of or inside the target cell.
This interaction between the hormone and the receptor initiates new processes and functions in the target cell.
The Action Of Hormones: the hormone binds to its receptor either on the surface of or inside the target cell, which in turn initiates important processes in that cell. Figure from reference 2
Let’s take an example that women experience every month: our menstrual cycle.
In this case the endocrine gland is our ovaries, that produces the hormone estradiol (an estrogen), that targets the endometrial cells, initiating maturation of our endometrium (the lining of our uterus), preparing the uterus for a potentially fertilized egg. See?! Endocrinology is easy peasy 😉
An example of how hormones work. Illustrated by our hormone estradiol that induces maturation of our endometrium during our menstrual cycle.
How Do We Get Exposed To EDCs?
In my next blog post, What Are Endocrine Disrupting Chemicals? Part Two, you can read about where we meet endocrine disrupting chemicals in our everyday life and their consequences on our health.
XO Cæcilie Johansen, Medical Doctor, Denmark