Interview: Dr. Susan Nagel, PhD

BY ON April 4, 2014

Susan Nagel

This is an interview with Dr. Susan Nagel, PhD, Associate Professor of Obstetrics, Gynecology, and Women’s Health at the University of Missouri School of Medicine:

MCAF: Can you tell us what an endocrine disrupting chemical is?

Dr. Susan Nagel: An endocrine disrupting chemical as defined by the Endocrine Society is any chemical or group of chemicals that can disrupt normal hormone function.

Why should we be concerned about these chemicals?

We know from studies in the laboratory and even in people that exposure is associated with infertility and behavioral problems in children, and longer-term with immune dysfunction, obesity, diabetes, and cardiovascular disease.

We used to think that the dose made the poison, and we understood toxicology in terms of how chemicals affected adults. But we’re hearing more about how endocrine disrupting chemicals (EDCs) affect children even before they’re born. Can you help us understand that?

This is exquisitely important for developing individuals. So, exposure during that time can slightly alter the course of development with very large impacts in adulthood. This field is called “the developmental origins of adult disease.” So exposure during development and early childhood is associated with permanent, lifelong effects that sometimes we can’t even see at the time of exposure. Oftentimes we can’t see it because the [short-term] effects are subtle. Hormones work at very low concentrations, therefore EDCs can work at very low concentrations to disrupt normal hormones.

This can go one, even two generations ahead, causing problems?

There is some data to suggest that these effects can be transgenerational, yes.

Are there EDCs in the air we breathe?

There are. Certainly there are all kinds of endocrine disrupting chemicals in the air. Groups of chemicals like phthalates are actually used, for example, in air fresheners to help distribute the quality of that air freshener. They’re also used in perfumes, for example. Phthalates are a group of chemicals that have been shown to have endocrine disrupting activity, weak estrogenic activity and anti-androgenic activity, androgen being the male sex hormone.

What about something like fracking, where we don’t always know what chemicals are being used and emitted? Do we need more research in this area to understand what’s happening with those substances in the air?

We have a little bit of information, enough to know that we need to know more. There have been studies of air quality associated with fracking that show large blips of exposure with fracking. And some of those chemicals we have tested in the lab, for example, and we know that those are endocrine disrupting chemicals. So, there’s been a very few studies of the health outcomes associated with that kind of exposure, enough to know that, for example, in areas of dense drilling activity, those people have an increased risk of some types of cancer, and even some types of birth defects like heart defects in those babies born to moms that lived in very drilling-dense areas.

If there were more information about these EDCs in the air, how could that information help affect policy? Could it affect policy in a way that protects human health?

That’s a tough question. The way we regulate chemicals in this country is on a single chemical by chemical basis. So we are really struggling to come up with ways to regulate when we get an exposure through air or water, when it’s many, many, many chemicals that can act in a similar way at times, so it can really add up. Therefore if you were exposed to just one chemical, it may not have an effect, but we’re exposed to hundreds of chemicals every day.

What else would you want members of Moms Clean Air Force to know? What can they do to help us have cleaner air?

Less is more when it comes to chemical exposure. Just the mindfulness of how many chemicals we use in our homes every day and that are in our environment that we can potentially choose not to use. We can’t control obviously outdoor air quality. But the mindfulness of the chemicals we can control, I think, is a very good place to start.


TOPICS: Toxics