The endocrine system is a network of glands that produces all the hormones used by the body. In addition to well-known sex hormones like testosterone and estrogen, it also secretes important hormones like insulin and adrenaline.
Endocrine disruptors are chemicals that interfere with this system. They are also known as endocrine-disrupting chemicals or EDCs. Scientists are interested in the effects of endocrine disruptors on human health, and you can take advantage of their research to improve your health.
What Do Endocrine Disruptors Do?
Endocrine disruptors can affect the body in three main ways:
- They may block the pathway between a natural hormone and a receptor.
- They may act directly on a gland, causing it to make too much or too little of a hormone.
- They may mimic a hormone, causing the body to overreact or to react at the wrong time.
Sources of Endocrine Disruptors
Endocrine disruptors can be natural or manufactured chemicals. They usually enter the body through inhalation, in food, or by direct contact. They fall into these general categories:
- Heavy metals
Examples of endocrine disruptors include:
- Bisphenol A (BPA). Some food storage containers contain this chemical.
- Dioxins. Some manufacturing processes create dioxins, and they spread when certain substances burn.
- Perfluoroalkyl and Polyfluoroalkyl Substances (PFAS). These substances are used in non-stick coatings.
- Phthalates. Makers of plastics use phthalates to make their products more pliable.
- Polychlorinated biphenyls (PCB). PCBs are found in many products in and around the home, including transformers and lubricants.
- Triclosan. Once used in soap and hand sanitizers, this chemical is still present in other products designed to kill bacteria.
Endocrine Disruption in Wildlife
The effect of endocrine disruptors on wildlife is well-documented. Pesticides, fungicides, and herbicides often contain EDCs. They can contaminate soil, air, and water and affect wildlife.
The impact of one endocrine disruptor is well-known: Dichlorodiphenyltrichloroethane (DDT) caused eagles, condors, and pelicans to produce eggs with very thin shells, killing many baby birds. DDT also caused sea lions to give birth prematurely.
More recently, scientists have linked EDCs with high numbers of frogs and swordfish with intersex characteristics.
Endocrine Disruption in Humans
Scientists have documented endocrine disruption in wildlife and in lab animals. They have been less successful in proving that endocrine disruption occurs in humans. It's similarly difficult to determine how these chemicals affect humans, although many researchers believe they do.
Because certain diseases have increased in recent years along with humans' use of chemicals, many scientists connect the two events. They say that genetic changes do not occur fast enough to explain the growth of these diseases. Some of these conditions are part of the endocrine system, leading some scientists to conclude that EDCs are to blame.
There is proof of human endocrine disruption in one well-known case, though. Many women took diethylstilbestrol (DES), a synthetic estrogen, from 1940 to 1971. Their doctors gave them the drug to treat problematic pregnancies. Years later, doctors discovered that the daughters of women who took DES had a higher risk of several types of cancer. Scientists are closely watching the next generation of women, the DES granddaughters, to see if they have problems, too.
The Difficulty of Human Studies
There are many reasons why it's difficult to study endocrine disruption in humans, including:
Number and diversity of chemicals. There are hundreds of substances suspected of being endocrine-disrupting chemicals (EDCs). There are probably many more that could be added to the list. These chemicals have very different properties. Testing them individually is a giant task.
Exposure to multiple chemicals. Since chemicals are everywhere in our world, humans are constantly exposed to more than one chemical at a time. That makes it difficult to isolate the effect of a single chemical.
Cumulative effects. Many EDCs accumulate in fat. They can stay there for years and can combine with other EDCs or react to them. No one knows what the effects of these mixtures could be.
Research About Endocrine Disruptors
Researchers are studying the effects of some common endocrine disruptors. One study looked at whether EDCs might increase the symptoms of attention deficit hyperactivity disorder (ADHD). In this study, teen males gave urine samples that were tested for endocrine disruptors. The young men with more EDCs in their urine also displayed more notable ADHD behaviors.
Researchers see connections between several other conditions and exposure to EDCs. Clear-cut evidence is lacking, but research continues. Researchers are looking at the effects of EDCs on:
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:
- Buyorganic 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 certainly 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.