How Are People Exposed to Harmful Endocrine-Disrupting Chemicals?

More than 97% of U.S. adults have at least one chemical in their body that is known to disrupt their sensitive hormone system. And because hormones are essential to many functions of the human body—from reproduction and puberty to metabolism and immunity—these chemicals have been linked to an array of health effects, including infertility, low birth weight and preterm birth, diabetes, heart disease, and hormone-related cancers.

Virtually ubiquitous in the environment and common in consumer products, these compounds—known broadly as endocrine-disrupting chemicals (EDCs)—can be ingested, inhaled, or absorbed through the skin. Here are some of the most common pathways through which people are exposed to some of the most harmful EDCs.

• Food, food packaging, and farmland. EDCs can make their way into food through packaging and processing equipment made from plastic or treated with chemicals such as per- and polyfluoroalkyl substances (PFAS) that make surfaces resistant to water, heat, and grease. PFAS can also enter the food supply through farmland when they contaminate fertilizer made from treated municipal waste.
• Drinking water. EDCs released from manufacturing facilities can enter reservoirs, wells, and other sources of drinking water. In addition, fertilizers and pesticides that contain EDCs can contaminate ground and surface water when applied to farmland. The U.S. Geological Survey estimates that 45% of U.S. tap water is contaminated by one or more PFAS.
• Children’s toys and baby products. Also known as “everywhere chemicals,” two kinds of EDCs are commonly used in plastic: bisphenols, such as bisphenol A (BPA), and phthalates. As a result, they are often found in baby bottles, pacifiers, teethers, toys, and many other plastic products. Research shows that babies and children ingest and inhale these chemicals and absorb them through the skin, which poses unique, long-term risks at these sensitive stages of development.
• Cosmetics and personal care products. Phthalates are used in these products for a variety of reasons, such as to reduce cracking in nail polish, keep hairspray from hardening too much, and make fragrances last longer and spread farther.
• Construction materials. EDCs are common in plastics, adhesives, flame retardant treatments, and other materials and substances used to build the spaces where people spend much of their time, including homes, schools, and offices. Research shows that some long-banned or restricted EDCs, such as brominated flame retardants, are “still widely detected in indoor dust in most countries”—though their concentrations are falling—and that levels of certain substitute chemicals that also disrupt the human hormone system are rising.
• Clothing. Bisphenols are a common component of polyester, PFAS can make clothes resistant to stains, and phthalates can soften the ink used to print images on fabric—to name just a few EDCs and their uses. EDCs can also migrate unintentionally into clothing via manufacturing processes and have been found in cotton, which may pose particular hazards to infants who absorb the chemicals through their skin.

Pew’s safer chemicals project is working to reduce the American public’s exposure to harmful EDCs by clarifying and communicating the scientific evidence, strengthening public policy governing the chemicals, and working with corporations to increase their transparency and use of safer chemical alternatives.

Jennifer McPartland directs The Pew Charitable Trusts’ safer chemicals project, and Josh Wenderoff works on Pew's health programs.