In this article, I will go over endocrine disruptors that disrupt normal hormonal health. Let’s first start with the definition and work of the endocrine system.

What is the endocrine system and what are its functions?

The endocrine system is a complex network of glands, hormones, and receptors. It provides the key communication and control link between the nervous system and bodily functions such as reproduction, immunity, metabolism, and behavior.

In nearly all complex multicellular animals, there are two main systems controlling and coordinating the processes within the body:

  • The nervous system exerts rapid point-to-point control by means of electrical signals passing down the nerves to particular organs or tissues.
  • The endocrine system, is a slower system based on chemical messengers, the hormones, which are secreted into the blood (or other extracellular fluids) and can reach all parts of the body.

The nervous system works in tandem with the endocrine system to control all bodily functions and processes. The endocrine system has three main components:

Endocrine glands are situated at various sites around the body, and in specialized areas of the brain. The cells in these glands secrete specific chemicals called hormones.

Hormones circulate around the body via the bloodstream and modulate cellular or organ functions by binding with receptors in the target cells. Hormones that stimulate and control the activity of other endocrine glands are called trophic hormones.

Receptors in the target cells, once activated by binding of the hormone, regulate the functions and processes in the tissue through interactions with the cell’s DNA or other complex intracellular signaling processes.

The main human hormones and their functions are shown below :

HypothalamusReleasing hormonesStimulate pituitary activity
PituitaryTrophic (stimulating) hormonesStimulate thyroid, adrenal, gonadal and pancreatic activity
ThyroidThyroid hormonesRegulate metabolism, growth and development, behaviour and puberty
AdrenalCorticosteroid hormones CatecholaminesRegulate metabolism Regulate behaviour
PancreasInsulin and glucagonRegulate blood sugar levels
GonadsSex steroid hormones (androgens and oestrogens)Regulate development & growth, reproduction, immunity, onset of puberty and behaviour

The production and circulating levels of hormones are controlled by means of negative feedback processes. For example, the synthesis of thyroid hormone is stimulated by thyroid-stimulating hormone (TSH) produced by the pituitary gland. If blood levels of thyroid hormone fall, a part of the brain, the hypothalamus, responds to the change and releases thyroid hormone-releasing hormone (TRH), which stimulates a particular cell type in the pituitary to increase TSH synthesis. As thyroid hormone levels in blood again rise in response to TSH, TRH production is reduced and, in turn, TSH secretion is suppressed. Such feedback systems maintain the balance of various body systems (operating in a fashion analogous to the system that controls a domestic central heating system) - a process known as homeostasis.

Excerpt from: European Commission

What are some of the examples of hormones and their functions?

Some examples of hormones secreted by the endocrine system are:

  • ACTH (adrenocorticotrophic hormone) - is produced by the pituitary gland to influence the release of corticosteroid hormones from the adrenal glands.
  • ADH (antidiuretic hormone, vasopressin) - is produced by the pituitary gland to stimulate water reabsorption by the kidney tubules.
  • Adrenaline (epinephrine) and noradrenaline (norepinephrine) - are two hormones formed in the adrenal gland that help the body to react (e.g., flight or fight, body defense mechanisms) under stressful conditions (they can increase the heart rate, blood pressure, blood sugar levels, blood clotting rate).
  • Estrogen - a female sex hormone produced by the ovaries prior to ovulation
  • Testosterone - is a male sex hormone produced by the testes, ovaries, and adrenal glands.
  • Insulin - is secreted by the pancreas and regulates the storage and use of carbohydrates in the body.
  • Thyroid hormone - is produced in the thyroid and influences the function of virtually every cell in the body (growth, development, and metabolism).
  • Progesterone - a female hormone that is secreted by ovaries after ovulation. Necessary for childbearing & birth

What are endocrine disruptors?

Chemicals are an essential component of our daily lives. But some chemicals, known as endocrine disruptors, can have harmful effects on the body’s endocrine (hormone) system. Hormones act in very small amounts and at precise moments in time to regulate the body’s development, growth, reproduction, metabolism, immunity, and behavior. Endocrine disruptors interfere with natural hormone systems, and the health effects can be felt long after the exposure has stopped. Exposure to endocrine disruptors in the womb can have life-long effects and can even have consequences for the next generation.

What are the mechanisms of disruption?

Some chemicals can act on the endocrine system to disturb the homeostatic mechanisms of the body or to initiate processes at abnormal times in the life cycle. The chemicals can exert their effects through a number of different mechanisms:

  • They may mimic the biological activity of a hormone by binding to a cellular receptor, leading to an unwarranted response by initiating the cell’s normal response to the naturally occurring hormone at the wrong time or to an excessive extent (agonistic effect).
  • They may bind to the receptor but not activate it. Instead, the presence of the chemical on the receptor will prevent the binding of the natural hormone (antagonistic effect).
  • They may bind to transport proteins in the blood, thus altering the amounts of natural hormones that are present in the circulation.
  • They may interfere with the metabolic processes in the body, affecting the synthesis or breakdown rates of the natural hormones.

What are the types of endocrine disruptors?

  1. Natural Hormones:
    Released into the environment from an animal and chemicals produced by one species that exert hormonal actions on other animals. For example, human hormones unintentionally reactivated during the processing of human waste in sewage effluent may result in changes to fish.
  2. Natural Chemicals:
    Includes toxins produced by components of plants (the so-called phytoestrogens, such as genistein or coumestrol) and certain fungi.
  3. Synthetically Produced Pharmaceuticals:
    These are intended to be highly hormonally active. Examples include the contraceptive pill and treatments for hormone-responsive cancers. These may also be detected in sewage effluent.
  4. Man-made Chemicals:
    and by-products released into the environment. Laboratory experiments have suggested that some man-made chemicals might be able to cause endocrine changes. These include some pesticides (including DDT and other chlorinated compounds), chemicals in some consumer and medical products (such as some plastic additives), and a number of industrial chemicals including polychlorinated biphenyls (PCBs) and dioxins).

What are the known endocrine disruptors?

  1. Fluoride - Commonly in tap water, and fluoride toothpaste among other fluoride products
  2. Bisphenol A (BPA), Phthalates & Phenol - Found in plastics and food storage materials
  3. Fabrics that are treated with flame retardants
  4. Most products with fragrance, and anti-bacterial soaps
  5. Soy-based products - Contain phytoestrogens, which are chemicals produced by plants that mimic estrogen
  6. DDT, Chlorpyrifos, Atrazine, 2, 4-D & Glyphosate - Found in pesticides
  7. Lead & cadmium
  8. Polychlorinated biphenyls (PCBs), Brominated Flame Retardants & Dioxins - Found in industrial solvents, lubricants, electronics, and building materials
  9. Parabens & UV Filters - Found in personal care products, medical tubing, and sunscreen
  10. Triclosan - Found in antibacterial soaps and Colgate total
  11. Perfluorochemicals - Found in textiles, clothing, non-stick food wrappers, microwave popcorn bags, and old Teflon cookware
  12. Insecticides & Pesticides
  13. Most cosmetics
  14. Perfluoroalkyl and Polyfluoroalkyl Substances (PFAS) - Used in non-stick coated pans and cookware

What are the effects of endocrine disruptors?

Response to psychological stress
  • Neurological and behavioral changes
  • Reduced ability to handle stress
  • Some EDCs have been linked to obesity and type 2 diabetes
  • Some industrial chemicals and flame retardants can interfere with thyroid function
  • Some classes of EDCs (DDT, BPA, phthalates, PCBs, and others) can affect reproductive health by mimicking or blocking the effects of male and female sex hormones this, in turn, causes low sperm count and infertility, especially in men
Growth and development
  • High exposures to EDCs during gestation can lead to low-birth-weight
  • Altered development
  • Disrupted sexual development
  • Weakened immune system
  • Exposure to estrogen or androgen mimicking EDCs can promote breast and prostate cancer growth and/or interfere with hormonal cancer therapy
  • Prenatal exposure to some EDCs may after mammary gland development and increase breast cancer risk later-in-life

How to Avoid Endocrine Disruptors

You can’t eliminate all contact with endocrine disruptors, but you can reduce your contact. Try these strategies when cleaning or cooking:

  • Buy organic produce. If organic food is not available or you can’t afford it, wash your produce well, or peel it if possible.
  • Buy simple foods. Choose foods that are less processed and come with a minimum of packaging.
  • Choose products that don’t contain fragrances. Manufacturers don’t have to disclose what chemicals they use to make fragrances, but they are certain chemicals you don’t need.
  • Wash your hands often. By doing so, you’ll get rid of chemicals that you may have picked up. Choose the plainest soap you can find, one without antibacterial properties or a fragrance. Your hands will get cleaner if you rub them briskly.
  • Avoid plastics. See how many plastic products you can eliminate in your home. Store foods in glass or stainless steel.
  • Keep it clean. Reduce particles of chemicals in the home by vacuuming often and wiping away dust with a damp cloth. Choose a vacuum cleaner with a HEPA filter and change other air filters often.
  • Choose basic cleaners. Use vinegar, baking soda, and other basic cleaners as much as possible. If you need something stronger, look for a product that lists its ingredients.
  • Increase animal protein and animal fat intake. This for example will raise testosterone and balance other key hormones due to the fact most hormones are made from protein and cholesterol. Animal protein and fat are chemically similar to our own hence making it easier to convert into the much-needed resources for hormonal protein synthesis
  • Filter tap water. Tap water contains fluoride, estrogen, and a number of other endocrine disruptors and toxic chemicals. Choose a filter that uses solid block carbon.
  • Avoid canned foods. Canned foods are lined with PBA.
  • Switch to fluoride-free toothpaste

That’s it for today. Let me know if you’d like me to cover a topic. This is not medical advice and as such do your own research. Seek professional medical advice.

See Also