What Are ‘Hormone-Disrupting Chemicals’?

Get familiar with these everyday toxins
woman shopping for cosmetics that will do no harm

Have you ever perused the cosmetics aisle and noticed that some products say “paraben-free” and “phthalate-free” on their packaging? You know to mentally award these products some bonus points — but do you know what those claims actually mean?

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Every day we come in contact with chemicals (including parabens and phthalates) that experts think, over time, could mess with how our body’s hormones function. These are called hormone- or endocrine-disrupting chemicals, or EDCs.

They’re in food packaging, household and personal care products, and even in the air that we breathe.

“They’re essentially everywhere,” says endocrinologist Shirisha Avadhanula, MD. “We’re consuming them, we’re putting them on our bodies, we’re being exposed to them, and most of the time we don’t even know it.”

If you just felt a twinge of anxiety, take heart — this doesn’t mean you need to throw away everything in your cabinets. But Dr. Avadhanula says that becoming aware of EDCs and paying more attention to the products you use is an excellent step to take.

“We should be really looking at the things that we’re buying and being conscious of the potentially disruptive substances that we’re not only putting in our bodies but on our bodies,” she says.

Hormones: The chemical messengers

The intricate endocrine system is made up of many glands throughout your body, including the pituitary gland, ovaries or testes, and thyroid. These glands secrete hormones that enter your circulatory system and bind with receptors in other parts of the body, signaling to your organs and tissues what to do and when to do it.

Hormones help regulate many bodily functions, including:

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  • Growth and development.
  • Blood sugar control.
  • Metabolism and energy.
  • Blood pressure.
  • Reproductive processes.
  • Appetite and weight control.
  • Digestion.
  • Sleep cycles.
  • Mood.

Hormones, disrupted

The term endocrine-disrupting chemical refers to a manmade chemical that can interfere with your body’s hormone functioning. There are hundreds of chemicals thought to have hormone-disrupting effects, but Dr. Avadhanula says the most widespread and well-studied ones fall into four categories:

  • Bisphenols, including bisphenol A (BPA): BPA is found in food and beverage packaging, adhesives and many other consumer products. It can leach into foods and beverages that we consume, or enter the body through the skin. Studies have shown that most people have at least some BPA in their body.
  • Phthalates: Phthalates are used to make plastics, or as dissolving agents for other materials. They’re found in packaging, medical tubing, detergents, automotive parts, cosmetics and many other products that we touch every day.
  • Polychlorinated biphenyls (PCBs): These chemicals have been banned in the U.S. since the late 1970s but were widely used for decades prior to that in electrical equipment, paints, dyes, plastics and rubber products. They remain in the environment.
  • Dichlorodiphenyltrichloroethanes (DDTs) and dichlorodiphenyldichloroethylenes (DDEs): These are also environmental pollutants. DDE is a breakdown product of DDT, which is banned in the U.S. but is still used in other countries as a pesticide.

Some of these chemicals disrupt the endocrine system by mimicking hormones and tricking our bodies. Others block hormones from doing their job.

“EDCs can disrupt a hormone’s pathway at any point — from its secretion from the gland, or its transport through the circulatory system, or its binding to a receptor,” Dr. Avadhanula explains. “You can imagine that exposure to these chemicals would cause disarray in your body.”

Because of the various ways they can work, they are thought to contribute to an array of health problems over time.

Studies have linked high levels of BPA, for example, with heart problems and a greater risk of hormone-related cancers, among other things. Exposure to phthalates has been associated with decreased sperm quality in adult men. PCBs are thought to be especially dangerous to the health and development of babies in the womb.

“There’s also a suggestion that exposure to EDCs can potentially play a role in the development of obesity and type 2 diabetes,” Dr. Avadhanula adds.

But studying the effects of these chemicals in humans is challenging for scientists. Much of experts’ current understanding is based on animal research or studies of trends in large populations.

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“It’s very difficult to measure some of these chemicals in humans, and there aren’t biochemical tests for many of them,” Dr. Avadhanula explains. Plus, we’re exposed to many of these chemicals at once, so it’s hard to isolate their effects. It’s also likely that those effects develop over long periods of time.

We need more studies to better understand the risk to humans, she says.

What you can do

While scientists work to better understand how EDCs work, Dr. Avadhanula says the best thing concerned consumers can do is make more informed choices.

Here are some tips for minimizing your exposure:

  • Consider choosing products with BPA- and phthalate-free packaging.
  • Drink tap water that has been filtered.
  • Avoid microwaving plastics.
  • Avoid personal care products that list “fragrance” as an ingredient, as phthalates often hide in fragrances.
  • Choose products labeled “phthalate-free,” “paraben-free” or “BPA-free.”
  • Avoid unnecessary exposure to industrial chemicals and pesticides.

“We can’t underestimate the power of the single consumer,” Dr. Avadhanula says. “I’m happy that, as a society, we’re becoming a lot more cognizant of what we’re consuming, what we’re exposing our bodies to and the effects of our environment on our bodies.”

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