- Denise Scott
Have you heard about these? I had not until the last couple of years. My goal in choosing this topic is to create awareness. Due to my background in pediatric endocrinology, I find this information fascinating and frightening. However, knowledge is power, thus being educated is the best way to protect ourselves and our children.
There is much information to dispense, so I have divided this topic into two parts. This article will discuss what endocrine disruptors are and why these are of concern. Next week I will outline practical information on how to avoid them to protect your families. Because they are so pervasive and in so many products, these articles will go beyond food products.
EDCs are chemicals that can sometimes act as hormones
WHAT ARE ENDOCRINE-DISRUPTING CHEMICALS (EDCs)??
I will explain what EDCs are and then list the many known entities so that you will have names to look for when you make purchases.
EDCs are synthetic chemicals in thousands of products, including plastics, metal cans, fragrances, cleaning supplies, cookware, flame-retardant items, and pesticides.
Some you may have heard of, and others may be unfamiliar. This list is not complete but contains the most prevalently used EDCs. Of the hundreds of thousands of man-made chemicals, estimates are that about 1,000 may have endocrine-acting properties.
The impact of one endocrine disruptor is well-known: Dichlorodiphenyltrichloroethane (DDT) caused a number of birds to produce eggs with abnormally thin shells, killing many of their offspring.
Another well-known EDC case in humans involved a drug given to women to prevent miscarriage and premature birth, diethylstilbestrol or DES. This medicine was used from 1940 to 1971 until the discovery that the daughters of women treated had a higher risk for several types of cancer, including vaginal, uterine, and breast.
What are some known endocrine disruptors?
Bisphenol A (BPA) — used to make polycarbonate plastics and epoxy resins, found in many plastic products, food storage containers, the lining of canned foods, the paper used for receipts, and plastic water bottles. This chemical can bind to estrogen receptors and has been implicated in many adverse effects. BPA is one of the most common EDCs made in the greatest volume.
Chlorpyrifos — a widely used insecticide commonly sprayed on crops
Dioxins — produced as a byproduct in herbicide/pesticide production and paper bleaching; these leak into the environment during waste burning and wildfires; they can accumulate in the food chain, mainly in the fatty tissue of animals. They tend to be higher in meat, eggs, fish, and dairy than in plant-based foods. Dioxins break down very slowly and tend to stay in the environment.
Perchlorate — a by-product of aerospace, weapon, and pharmaceutical industries found in drinking water and fireworks. This compound is known to lower thyroid hormone production by inhibiting iodine uptake by the thyroid gland.
Perfluoroalkyl and Polyfluoroalkyl Substances (PFAS) — used widely in industrial applications, such as firefighting foams and non-stick pans, paper, and textile coatings. Perfluorinated compounds (PFCs) have been used for more than 60 years and make materials stain- and stick-resistant, water-proof, and grease-resistant (think Scotchgard and Teflon). They are present in clothing, textiles, non-stick food wrappers, the inner lining of microwave popcorn bags and pizza boxes, and old Teflon cookware. Drinking water is a common source of exposure due to contamination.
Phthalates — used to make plastics more flexible; these are in some food packaging, cosmetics, fragranced items, personal care items, children’s toys, and medical devices. Look for any name with -phthalate at the end.
Phytoestrogens — naturally occurring substances in plants that have hormone-like activity, such as genistein and daidzein that are in soy products, like tofu or soy milk.
Polybrominated diphenyl ethers (PBDE) — used to make flame retardants for household products such as furniture foam and carpets.
Polychlorinated biphenyls (PCB) — used to make electrical equipment like transformers and in hydraulic fluids, industrial solvents, and lubricants.
Triclosan and Triclocarban — are the most commonly used antimicrobials found in numerous consumer products, such as antibacterial soaps, deodorants, toothpaste, and cosmetics, and in furniture, toys, kitchenware, and clothing. Triclosan also goes by the names Microban® (when used on plastics and clothes) and Biofresh® (when used in acrylic fibers).
Additional chemicals include lead, mercury, and cadmium.
You cannot avoid these entirely, but knowing the chemicals to look for in products can help you minimize your exposure. We are exposed to these chemicals through air, food, water, and absorption through our skin.
Usual Sources of EDC Exposures:
Industrial chemicals and pesticides can leach into soil and groundwater, building up in fish and animals, making their way into the food chain.
Some products are packaged in containers with or have EDCs, such as household cleaning products, fabrics treated with flame retardants, cosmetics, lotions, products with fragrances, and antibacterial soaps.
Processed foods can accumulate traces of EDCs that leach out of materials used in manufacturing, processing, transportation, and storage.
Pesticide residues can be present in non-organic produce.
Soy-based products contain phytoestrogens, which are chemicals produced by plants that mimic estrogen.
Household dust can contain EDCs such as lead, flame retardants, and PCBs from construction material or that accumulate from other items in the home.
Why should we know or worry about EDCs?
EDCs can interfere with normal hormones
The endocrine system is a network of organs and glands in our body that make, store, and secrete hormones. These hormones, such as thyroid and growth hormones, help regulate many bodily functions, including growth, puberty, reproduction, metabolism, and energy balance. All hormones work by attaching to a specific receptor to elicit a reaction. EDCs can interfere with this process.
EDCs are synthetic chemicals that can mimic our natural hormones and interfere with normal hormonal function and interactions.
These chemicals, when absorbed by the body can:
Decrease or increase normal hormone levels
Mimic the body’s natural hormones (act as a hormone)
Block the path between the hormone and receptor, affecting the body’s own production or action of hormones
Some can change how sensitive we are to a hormone.
EDCs are linked to numerous health problems and include:
Fertility problems, endometriosis, early puberty, altered nervous system function, immune function, certain cancers, respiratory problems like asthma, metabolic issues, diabetes, obesity, cardiovascular problems, neurological problems, learning disabilities, and more. They can be transferred from a mother to her fetus or an infant through breastfeeding if a mother has them in her body.
The most important information is that EDCs have the most significant impact during periods when accelerated development occurs - both in utero, to a developing fetus, and during childhood when more rapid growth occurs. A developing fetus and infant are more vulnerable than an adult because organ systems are still developing. High EDC exposure during fetal development can sometimes have long-lasting and irreversible effects. Chronic high exposures have the highest risk. Included are the thousands of chemicals in cigarette smoke which affect children before and after birth through secondhand smoke. Pregnant women and children need the most protection from these chemicals to avoid long-term damage.
Pregnant women are at risk from EDCs due to potential harm to a fetus
A developing fetus is exposed to chemicals in the mother through the placenta. There seem to be specific windows of vulnerability in development when chemicals can have long-term, irreversible effects on reproductive and neurological systems.
Children are more vulnerable to the effects of EDCs than adults for several reasons:
They are rapidly growing and developing
Their immune systems are not fully developed
Relative to their body weight, they ingest more food and water
They have a higher skin-to-body-mass ratio (can absorb more through their skin)
They are often outdoors, playing in the dirt, which can contain contaminants
Much more research is needed, but we know EDCs can affect:
Response to psychological stress
Growth and development
Next week I will explore how we can minimize exposure to these chemicals.
Several excellent resources to learn more are:
The Endocrine Society
The National Resources Defense Council (NRDC)
The Environmental Working Group (EWG)
Physicians for Social Responsibility (PSR)