What are Endocrine-Disrupting Chemicals?

• Latest News

Every week it seems there is more alarming news about the harmful health effects of endocrine-disrupting chemicals (EDCs, also called “hormone-disrupting chemicals”). EDCs are often found in plastic consumer products, as well as processed and plastic-packaged food and plastic bottled water. So what are EDCs, and should we be concerned? 

EDCs mimic, block, or otherwise interfere with the body’s hormones and cause problems throughout our bodies. Due to their widespread use, EDCs widely contaminate food, water, the environment, and our human bodies. When EDCs enter our bodies, they can cause our hormones to go haywire—and this can cause our bodies to respond to altered hormone signals in ways that hurt our health.

EDCs are Found in Plastics, Food, & Water

There are approximately 85,000 man-made chemicals in the world, with at least 1,000 classifiable as EDCs. The overall abundance and number of man-made chemicals surged during and after World War II. Production of EDCs, especially pesticides and plastics, continues to increase with industrial development. Significant amounts of man-made chemicals, including EDCs, have been released (intentionally and unintentionally) into the environment.

EDCs are widely used in industrial materials like firefighting foams, and manufacturing processes like herbicide production and paper bleaching. They are also used to make common products, including certain kinds of baby bottles, building materials, carpeting, children’s toys, clothing, cosmetics, electronics, food and beverage packaging, fragrances, furniture, personal care products, thermal cash register receipts, and many more—especially those made of plastics. Of the more than 16,000 chemicals used to make plastics, at least 4,200 of those chemicals are known to harm human and environmental health. Many of the known hazardous chemicals in plastics are EDCs. 

While some of the harmful effects of EDCs, such as infertility, were first observed decades ago, these dangerous substances continue to be used today. When added to plastics, EDCs can give certain useful functional and/or physical characteristics, including flame-retardant properties, flexibility, non-stick properties, and repelling liquids and stains. Though some EDCs have been phased out or used less after coming under regulatory scrutiny, many replacements concocted to succeed toxic predecessors have also been found to be harmful endocrine disruptors—this is known as “regrettable substitution.”

Exposure to EDCs can occur at any time during the entire endless toxic existence of plastic products, from manufacturing to consumer contact, recycling, to waste management and disposal, shipping and storage. We breathe EDCs in the air, ingest them with food and water, and can absorb them through our skin. Plastic items and plastic particles (microplastics and nanoplastics) alike have been shown to contain and leach EDCs into the environment, food, water, and animals’ bodies. Bioplastics, biocomposites, and so-called “biodegradable” plastics, which have been promoted as more ecological and healthy than plastics, contain similar chemical additives as conventional plastics that can have EDCs and break up into micro- and nano-particles.

How EDCs Harm Our Health

The body’s hormones act like the conductor of an orchestra: Hormones are natural chemicals that tell your body and its systems how and when they should turn up or turn down to carry out necessary functions. Hormones direct everything from body growth, to hunger and thirst, fertility and pregnancy, stress response, and much more.

Studies suggest that nearly all people have detectable levels of EDCs in their bodies. Bisphenol-A (BPA), polychlorinated biphenyls (PCBs), phthalates, and other industrial chemicals as well as heavy metals known to interfere with the body’s hormones have been detected in human blood, breast milk, fat, umbilical cord blood, and urine. PFAS, which are in the bodies of nearly all people living in the US, have been found in human fetuses.

Even what may seem like small changes in a person’s hormone levels can cause significant problems for their development and health. EDCs have been linked to the development of autoimmune disorders, hormone-sensitive cancers, obesity and metabolic dysfunction, neurological and behavioral disorders, nervous system damage, and reproductive problems such as infertility. 

The growing rates of health problems related to EDCs tracks with the increased production of manufactured chemicals, including the chemicals added to plastics.

Known Human Health Effects of EDCs:

Infertility and Exposure to EDCs are Strongly Linked

Infertility has been strongly linked to exposure to the EDCs in plastics. In her book Count Down: How Our Modern World Is Threatening Sperm Counts, Altering Male and Female Reproductive Development, and Imperiling the Future of the Human Race, Dr. Shanna Swan discusses how, in 2017, she and her team of researchers completed a major study finding that over the past four decades, sperm levels among men in Western countries have dropped by more than 50 percent. 

In men, exposure to EDCs are known to reduce sperm concentration, health, motility, and volume, and increase sperm DNA damage. Erectile dysfunction, which is also on the rise, has been linked to exposure to EDCs. EDCs have been connected to undescended testicles and urethra defects in men, which can also diminish fertility.

Women with early exposure to EDCs may experience earlier onset puberty that lengthens menstrual cycles and accelerates menopause. Lead, a heavy metal known to interfere with the body’s hormones, can also shorten a woman’s reproductive years. Women with higher exposure to EDCs are more likely to experience endometriosis and fibroids. Higher levels of EDCs, including BPA, have also been linked to ovarian cysts, which can reduce fertility. 

Interestingly, it appears that the amount of microplastics accumulating in men’s testicles is among the highest found in any human body part: higher than what has been found in mothers’ placentas, and second only to the human brain, the organ which appears to be harboring the highest levels of plastic particles.

Toxic air on the frontlines of petrochemical and plastics development contains EDCs and is linked to women’s infertility, and birth and pregnancy complications including pre-term and low-weight births and sometimes fatal preeclampsia. Other research has indicated that industrial air pollution and high temperatures linked to the climate crisis are also related to a higher incidence of stillbirth. Industrial air pollution has been linked to men’s infertility.

Babies, Children, & Youth are Most Vulnerable to EDCs

In young people, regularly functioning hormones are especially important for healthy growth, development, and body regulation. Even at relatively low levels of exposure, EDCs can cause harm. This is especially true in pregnant people, whose hormone systems kick into overdrive during and after pregnancy, and in babies, children, and youth whose hormone systems are also extremely active to guide healthy growth and development.

Some of the severe health problems linked to EDCs in children, infants, and unborn babies include: Cancer; neurodevelopmental problems; and metabolism disorders such as obesity, thyroid diseases, and reproductive and fertility issues. PFAS, a common plastic additive that lends nonstick qualities to cooking pans and food packaging, and waterproofing on synthetic rain jackets, in addition to pollution from petrochemical plants—which are used to refine plastic’s ingredients—are strongly linked to infertility in females.

Pregnant people with detectable levels of phthalates, an extremely common plastic additive found in everything from vinyl flooring to plastic food packaging, in their bodies are more likely to experience pre-term birth of their babies and other birth complications. In the womb, plastic’s chemicals can impair development of a baby’s brain and vital organs, leading to poor prenatal growth and future health problems. Babies, children, and youth exposed to plastic’s many forms of pollution may experience early puberty, metabolic problems like obesity, and other serious health problems.

The environment, food, and water are increasingly contaminated with plastic particles and the EDCs they carry as plastic production increases and plastic pollution worsens. Babies are exposed to plastic particles and chemicals from teething toys, synthetic clothing and textiles, plastic baby products like bottles and diapers, and household dust. Unfortunately, even breast milk is polluted with plastic and EDCs, and microplastics and EDCs that are added to plastics, like phthalates have been detected in the urine of breast-fed infants. Infants who are fed formula prepared in plastic (polypropylene) bottles ingest millions of plastic particles per day. Even baby bottles labeled “BPA-free” are not necessarily free of other EDCs.

EDCs and plastic particles affect public areas as well, like playgrounds and outdoor spaces, where babies and children recreate with their schoolmates, teachers, parents, and guardians. Playgrounds have been found to have microplastics with an average of five times higher concentration levels than areas outside this zone, due to plastic play equipment and ground coverings like artificial turf. Studies have shown that athletes who play on artificial turf are likely to have higher levels of PFAS in their bodies. Widespread use of plastics around children means that plastic particles and hormone-disrupting chemicals are widely found in children’s plastic toys, and in school supplies and classrooms

Scientists are finding more and more evidence of microplastics in human placentas, on both the maternal and fetal sides. There is evidence that EDCs can similarly cross the placental barrier through the umbilical cord. The presence of microplastics in women’s uteruses and EDCs in women’s blood have been linked to miscarriages. People born today are exposed to plastic pollution and its toxic chemical additives—including EDCs—inside of the womb and in their first moments of life onward.

We Need Policies to Help Eliminate Toxic Chemicals

On a systems level, scientists urge chemical simplification that will eliminate use of toxic chemicals, and new legislation has emerged to help eliminate EDCs. The European Union has had a Strategy on Endocrine Disruptors since 1999, which prioritizes EDC control and elimination measures, including a ban on endocrine-disrupting pesticides. Across the U.S., some states have passed legislation focused on eliminating certain EDCs, such as PFAS and bisphenols in food packaging. While progress is being made, scientists urge that more must be done to protect the public from EDCs, including greater transparency of ingredients in food packaging and phasing out the most hazardous chemicals in food packaging. 

We need legislative and regulatory solutions that address the plastic pollution crisis at the source, reduce plastic production and use, center environmental justice, extend producer responsibility by holding corporations accountable, and support a regenerative circular society free of plastic pollution and its toxic impacts.

How to Protect Yourself from EDCs

While we work to prevent our exposure to plastics and EDCs on a systemic level, there are things you can do now to reduce your exposure.

• On an individual level, first educate yourself about EDCs and where you can find them. Doing so can help you avoid items that contain these chemicals. 
• As a general rule, minimize your exposure to products that are made of or wrapped in plastic—including food and drinks in plastic; foam furniture; nonstick plastic cookware; plastic children’s toys and products; and synthetic textiles—especially those that are waterproofed.
• Look for healthy alternatives: opt for foods and beverages that are unpackaged and unprocessed; choose furniture, textiles, and toys made of natural fibers and materials; cook with cast iron, glass, stainless steel, wood, and other natural materials. 
• Wash your fruits and vegetables to remove pesticide residues, and when it comes to produce, try to eat more of the “Clean 15” and less of the “Dirty Dozen.” 
• If you do have any food or beverages in canned or plastic packaging, avoid storing these in hot areas, which can cause EDCs to leach from packaging into food or beverages. 

Single-use plastics are best replaced by plastic-free reusables. Refuse single-use plastics to avoid EDCs and all forms of plastic pollution.