Glossary: Understanding Endocrine-Disrupting Chemicals

Americans are regularly exposed to thousands of synthetic chemicals. While these substances can offer various benefits, some—including endocrine-disrupting chemicals (EDCs)—are also hazardous to human health.

This glossary helps explain what EDCs are and some of the terms associated with these substances.

aggregate exposure

Refers to the total exposure to an EDC that a person experiences from multiple sources over time.

biomonitoring

The practice of tracking the presence of chemicals in the human body. The Centers for Disease Control and Prevention conducts biannual biomonitoring via the National Health and Nutrition Examination Survey, which measures exposure to a wide variety of chemicals, including about 30 individual EDCs, in a representative sample of the U.S. population.

bisphenols

Chemical compounds often used in the production of plastic and epoxy resins and found in various products, including eyewear, water bottles, and food storage containers.

class

A group of chemicals that share common traits. Some classes are based on chemical structure, such as per- and polyfluoroalkyl substances (PFAS), which are defined by their carbon-fluorine bonds. Classes of EDCs include PFAS, bisphenols, phthalates, and parabens.

cumulative effects

When people are exposed to multiple EDCs (or other toxins), which can interact with each other in the human body and exacerbate or alter the effect they have on human health.

endocrine-disrupting chemicals (EDCs)

Sometimes referred to as hormone-disrupting chemicals, these are synthetic compounds that interfere with human hormone systems. People are exposed to the many different types of EDCs through a wide range of consumer products, such as food packaging, cookware, children’s toys, cosmetics, carpets, and construction materials. EDCs—such as PFAS, bisphenols, and phthalates—are increasingly found in drinking water, on farmland, and throughout the environment. Once ingested, inhaled, or absorbed through the skin, they can interfere with the human hormone system, which controls pregnancy, prenatal and early childhood development, puberty, metabolism, immune response, and aging. Many EDCs have been linked to numerous human problems, including infertility, abnormalities in sex organs, endometriosis, early puberty, certain cancers, respiratory issues, diabetes, obesity, cardiovascular disease, neurological and learning disabilities, and more.

endocrine system

A complex network of glands and organs that make hormones, which are essential to many different functions of the human body. Hormones serve as chemical messengers, sending signals that control human growth, development, metabolism, and reproduction.

exposure

Refers to humans and wildlife coming into contact with EDCs. Contact can occur through ingestion, inhalation, and absorption through the skin. Many EDCs can also be transferred during pregnancy, through the placenta, or via breastfeeding. Other exposure pathways for endocrine disruptors include food packaging, personal care products, clothing, carpeting, furniture, construction materials, food, drinking water, and farmland.

forever chemicals

A term used for synthetic per- and polyfluoroalkyl substances (PFAS), because these chemicals do not break down under natural conditions and persist in people and nature. Due to their widespread use, PFAS are found to be present in humans and animals throughout the world, as well as in food packaging and food products, drinking water, and the environment.

hormones

Naturally produced messenger chemicals that regulate human bodily functions and processes, including growth and development, metabolism, sexual function, reproduction, immune response, and mood.

hormone-disrupting chemicals

Another name for EDCs, synthetic chemicals that disrupt human hormone systems.

per- and polyfluoroalkyl substances (PFAS)

Sometimes referred to as “forever chemicals” and defined by their carbon-fluorine bonds, PFAS are a widely used, long-lasting chemical class that are found in cookware, cosmetics, food and food packaging, drinking water, and many consumer and industrial products. Research has determined that PFAS can be endocrine-disrupting. Due to their widespread use, PFAS are present in the blood and bodies of 97% of Americans.

phthalates

A class of EDCs, primarily used to increase the flexibility of plastic and enhance fragrance, among other functions. They are commonly found in food packaging, cosmetics, and children’s toys.

regrettable substitutions

The phenomenon in which one hazardous chemical is replaced with another. When bisphenol A (BPA) was removed from baby bottles, soda cans, and other food containers in 2008, some companies replaced it with two similar chemicals, BPS and BPF, that—like BPA—disrupt estrogen and testosterone. Growing evidence links each of these chemicals to many of the same health problems, such as cardiovascular disease, diabetes, and obesity.

safer alternatives

Chemical or other solutions—such as issuing e-receipts instead of paper receipts—that provide the same functionality as EDCs with fewer or no negative health impacts, as determined by scientific analysis.

vulnerable populations

Some people are at greater risk from EDCs than others. EDCs cause more serious harm at certain stages of development that rely on hormones. For example, pregnant women, their unborn children, infants, and adolescents are disproportionally affected by exposure to these hazardous chemicals.

Other populations are at heightened risk by virtue of their professions, including firefighters who are exposed to the chemicals in firefighting foam and gear, farmers who unknowingly use PFAS-laden waste as fertilizer, which contaminates soil, water, and food consumed by farmers and their families, neighbors, livestock, and consumers; and people who live near military bases, airports, and industrial manufacturing facilities, which are all significant sources of harmful pollution.