What are Endocrine Disrupting Chemicals?
By definition, endocrine disrupting chemicals are chemicals that may interfere with the body’s endocrine system (the system that keeps our bodies in balance, maintaining homoestasis and guides proper growth and development) and produce adverse developmental, reproductive, neurological, and immune effects in both humans and wildlife. According to The National Institute of Environmental Health Sciences a wide range of substances, both natural and man-made, are thought to cause endocrine disruption, including pharmaceuticals, dioxin and dioxin-like compounds, polychlorinated biphenyls, DDT and other pesticides, and plasticizers such as bisphenol A. Endocrine disruptors may be found in many everyday products– including plastic bottles, metal food cans, detergents, flame retardants, food, toys, cosmetics, and pesticides. Research shows that endocrine disruptors may pose the greatest risk during prenatal and early postnatal development when organ and neural systems are forming. It is interesting to note that even ten years ago, there simply was not the body of evidence that there is today about the body’s endocrine actions as well as the disease consequences of endocrine disrupting chemicals.
Endocrine disrupting chemicals can:
- Mimic or partly mimic naturally occurring hormones in the body like estrogens (the female sex hormone), androgens (the male sex hormone), and thyroid hormones, potentially producing over-stimulation.
- Pose the greatest risk during prenatal and early postnatal development when organ and neural systems are developing. In animals, adverse consequences, such as subfertility, premature reproductive senescence,and cancer, are linked to early exposure, but they may not be apparent until much later in life.
- Bind to a receptor within a cell and block the endogenous hormone from binding. The normal signal then fails to occur and the body fails to respond properly. Examples of chemicals that block or antagonize hormones are anti-estrogens and anti-androgens.
- Interfere or block the way natural hormones or their receptors are made or controlled, for example, by altering their metabolism in the liver.
- Reductions in male fertility and declines in the numbers of males born.
- Abnormalities in male reproductive organs.
- Female reproductive health issues, problems, early puberty, and early reproductive senescence.
- Increases in mammary, ovarian, and prostate cancers.
- Increases in immune and autoimmune diseases,and some neurodegenerative diseases
What are Xenoestrogens?
Xeno means foreign; therefore, xenoestrogens are literally foreign estrogens. Xenoestrogens are considered a type of xenohormone that imitates estrogen. They can be either synthetic or natural chemical compounds. Synthetic xenoestrogens are widely used industrial compounds, such as PCBs, BPA and phthalates, which have estrogenic effects on the body even though they differ chemically from the natural estrogenic substances produced internally by the endocrine system of the body. Xenoestrogens are also called “environmental hormones” or “EDC” (Endocrine Disrupting Compounds). Most scientists that study xenoestrogens, including The Endocrine Society, regard them as serious environmental hazards that have hormone disruptive effects on both wildlife and humans. Xenoestrogens have been introduced into the environment by industrial, agricultural and chemical companies and consumers only in the last 70 years.
Some of the 70,000 registered chemicals for use in the United States have hormonal effects in addition to toxic effects. These substances can increase the estrogen load in the body over time, and are difficult to detoxify through the liver (the main filter of your body). Scientists have also noticed changes in the age of onset of puberty and have come to the decision that it is a sign of the toxic chemical and hormonal onslaught that has become a part of our modern life.
There are two big — and by big I mean monumental — problems with the argument and the perspective taken by federal regulatory agencies and by the manufacturers of foods and medicines. The argument is that trace levels of these chemicals do no harm to human health. What that argument ignores is the cumulative effect of hundreds, if not thousands, of these chemicals entering and then mixing within the human body. This is known as the “body burden. ” We each carry a “body burden” of these synthetic chemicals. That is the problem of synergies; the synergistic reactions of two or more chemicals in the body. When they interact, it is much more powerful than any one individual chemical can do on its own. ~Randall Fitzgerald, author of The Hundred-Year Lie: How Food and Medicine are Destroying Your Health
Relationship Between Breast Cancer Risk, Estrogen, and Environmental Chemicals
Since there are many breast cancer cases that cannot be explained by known risk factors, some researchers suspect that environmental chemicals may play a role in breast cancer risk. Though there are many unanswered questions about whether environmental factors affect breast cancer risk, researchers have developed hypotheses about how environmental chemicals may affect breast cancer risk. These include chemicals that either mimic the effect of estrogen or that affect the levels of estrogen in the body indirectly by disrupting the way estrogen is produced or used in the body. Many different chemicals have been identified as being weak environmental estrogens. These include several pesticides (including some forms of DDT), the food preservatives BHT and BHA, the industrial detergent by-products nonyl- and octaphenol, compounds used in plastics including bisphenol A and some phthalates, the food dye Red #3, and the solvent formaldehyde which was used in carpet manufacturing, and is still used in making plywood.
Common Endocrine Disrupting Chemicals
Endocrine disruptors may be found in many everyday products– including plastic bottles, metal food cans, detergents, flame retardants, food, toys, cosmetics, and pesticides.
- Fire retardants
- Organophosphate pesticides & glycol ethers – Because this is very important, let’s pause here for an explanation. According to The Environmental Working Group – ” Neurotoxic organophosphate compounds that the Nazis produced in huge quantities for chemical warfare during World War II were luckily never used. After the war ended, American scientists used the same chemistry to develop a long line of pesticides that target the nervous systems of insects. Despite many studies linking organophosphate exposure to effects on brain development, behavior and fertility, they are still among the more common pesticides in use today. A few of the many ways that organophosphates can affect the human body include interfering with the way testosterone communicates with cells, lowering testosterone and altering thyroid hormone levels. Glyphosate (RoundUp) is an Organophosphate and known Endocrine Disruptor.
Can Xenoestrogens Act Synergistically?
In my opinion, this is a very important question. Study after study has revealed links between xenoestrogens and such health concerns such as decreased sperm viability, ovarian dysfunction, neurodevelopmental deficits, precocious puberty and obesity. But experimental limitations have prevented researchers to explore one of the most serious questions posed by exposure to xenoestrogens: what happens in the real world when an individual is exposed to multiple estrogen-mimicking chemicals at the same time? After all, humans and wildlife do not usually experience xenoestrogens as single compounds; but, in fact, they are most likely to be exposed to dozens of them simultaneously on a daily basis.
University of Texas Medical Branch (Galveston) researchers are now using new techniques that help study the synergistic effect on the body when it is exposed to low doses of multiple xenoestrogens. Even at low doses, the conclusions are quite concerning
Using cell cultures to test mixtures of three compounds known to affect estrogen signaling — bisphenol A (found in plastic bottles and the linings), bisphenol S (a supposedly safer replacement for bisphenol and recently found to have similar effects) and nonylphenol (a common component of industrial detergents and surfactants) – scientists have determined that combinations of endocrine disruptors can have a much greater effect than any one of them acting alone.
“We wanted to see how these persistent, ubiquitous contaminants affect estrogenic signaling when they’re mixed together as they are in nature, so we set up a cell-culture system that allowed us to test their influence on signaling by estradiol, the estrogen found in adult, cycling women,” said UTMB professor Cheryl Watson, senior author of a paper on the study now online in the journal Environmental Health. “What we found is that these things gang up on estradiol and thwart its response, which is not a good thing.”
Watson and her colleagues tested different mixtures of estrogen-disrupting compounds using rat pituitary cells which are master regulators of the animals’ endocrine systems. Their experiments measured the responses of key signaling pathways that lead to cell proliferation, the secretion of the pituitary hormone prolactin and the activation of proteins involved in apoptosis (programmed cell death), comparing the effects of estradiol alone with those of estradiol and mixtures of bisphenol A, bisphenol S and nonylphenol.
“These compounds work at very low concentrations — at the parts per trillion or parts per quadrillion level — and when you mix them together they affect estrogenic signaling differently and more dramatically than they do individually,” Watson said. “We need to pay attention to this, because estrogens influence so many things in both males and females — reproduction, the immune system, metabolism, bone growth, all sorts of important biological functions.”
It is very interesting to note that studies have detected measurable levels of bisphenol A and bisphenol S in the urine of more than 90 percent of Americans. Watson says that modern humans are exposed to dozens of xenoestrogens more or less continually.
One critical concern and obstacle to
identifying EDC (endocrine-disrupting
chemical) exposure and harm in humans
is that there can be a significant
lag time, possibly decades, between
exposure and the manifestation
of a clinical disorder.
“These things are all over the environment, and we need to know what they do so we can start figuring out what we need to change,” Watson said. “They’re probably disrupting and confusing hormones in people, and it’s important to find a way to prevent that as soon as we can. We need to test these compounds for their hormone-disrupting activities before they are put into products, so we can redesign for safety very early in the process.”
“To successfully study the impact of these chemical exposures, we must shift the burden of proof from the individual health care provider and the consumer to the manufacturers before any chemicals are even released into the environment,” Dr. Jeanne Conry, president of the American College of Obstetricians and Gynecologists, said in a statement.
Limiting Your Exposure to Endocrine Disrupting Chemicals
Below are some suggestions to employ that can help protect you and your family from toxic chemicals that act as xenoestrogens:
- Only use natural cleaning products in your home. Most health food stores will have these available or you can search online for them or even make them yourself.
- Avoid processed foods as much as possible. Cook at home and buy from local farmers’ market vendors who are using organic methods.
- Avoid artificial food additives of all kind, including artificial sweeteners and MSG.
- Avoid all varieties of unfermented soy.
- Switch to natural brands of personal care products such as shampoo, toothpaste, hair products, soaps, antiperspirants and cosmetics. Avoid fluoride.
- Avoid all synthetic and horse hormones (oral contraceptives and conventional HRT).
- Read Our Stolen Future, probably one of the best resources on this topic
- Avoid all pesticides, herbicides, and fungicides. Wash your food well to rid the pesticides. Bathe the washed food in a produce-wash (be sure to look at the ingredient list on the produce wash).
- Purchase effective water filters for your home, shower and kitchen faucet and ice maker.
- Use only organic or locally sourced whole foods when you can. Purchase free-range meats and dairy products. Be sure to ask if they have been fattened-up with grains before slaughter.
- Avoid all GMO foods and products.
- Avoid plastic goods as much as possible and never heat in them or place hot foods in plastic containers.
- Use tampons and sanitary napkins made of organic cotton without chlorine. (The FDA detected dioxins and dozens of other substances in conventional tampons. Look for ones that contain no chlorine, fragrance, wax, surfactants, rayon, etc.)
- If you use a microwave, do not microwave food in plastic containers and especially avoid the use of plastic wrap to cover food for microwaving. The best thing is to throw away your microwave.
- Use glass or ceramics to store food.
- Don’t drink water that is stored in any type of plastic container.
- Don’t use fabric softeners as it puts petrochemicals right on your skin. Vinegar is a great fabric softener!
- Use a “green” laundry and dish detergent with less chemicals.
- Computer monitors can emit a high level of electromagnetic frequencies (EMF). Use an EMF protection device.
- Keep your liver clean and supported. Perform a liver/gallbladder and colon cleanse at least two times yearly.
- Be aware that BPA-Free may not mean free of xenoestrogens. Plastics labeled BPA-free may not be Estrogen Activity-Free (Yang et al. 2011).
References & Research
René Viñas, Cheryl S Watson. Mixtures of xenoestrogens disrupt estradiol-induced non-genomic signaling and downstream functions in pituitary cells. Environmental Health, 2013; 12 (1): 26 DOI: 10.1186/1476-069X-12-26
Estrogen and Breast Cancer Risk: What Factors Might Affect a Woman’s Exposure to Estrogen? Breast Cancer and Environmental Risk Factors. Fact Sheet #10. Cornell University Program on Breast Cancer and Environmental Risk Factors in New York State (BCERF). Rachel Ann Clark, M.S. Science Writer, BCERF; Suzanne Snedeker, Ph.D. Research Project Leader, BCERF and Carol Devine, Ph.D, R.D. Division of Nutritional Sciences and Education Project Leader, BCERF
International Journal of Andrology, Apr 2010, 33(2):346-359, “Hypothesis: exposure to endocrine-disrupting chemicals may interfere with timing of puberty”
Yang CZ, Yaniger SI, Jordan VC, Klein DJ, & Bittner GD (2011). Most plastic products release estrogenic chemicals: a potential health problem that can be solved. Environmental health perspectives, 119 (7), 989-96 PMID: 21367689
TEDX List of Potential Endocrine Disruptors – Every chemical on the TEDX List has one or more verified citations to published, accessible, primary scientific research demonstrating effects on the endocrine system.
Scientific Statement on EDCs published by The Endocrine Society.
Our Stolen Future – The book Our Stolen Future, by Theo Colborn, Dianne Dumanoski and John Peterson Myers, brought world-wide attention to scientific discoveries about endocrine disruption. This website tracks the most recent developments, including the cutting edge of endocrine disruption science, ongoing policy debates and suggestions for consumers.
Environmental Health News – Environmental Health News provides access to hundreds of articles on environmental health topics published daily in the world press. Sign up for ‘Above the Fold’ to get daily news emailed right to your computer.
Environmental Working Group – Environmental Working Group specializes in providing useful resources for consumers to protect them from health problems attributed to a wide array of toxic contaminants.