The endocrine system and endocrine disruptors

Posted on May 08, 2009 by Susie Collins in Blog, Research

What are endocrine disruptors?

Post by Linda.

endocrinesystem Many of us have no idea what those enviros are talking about when they mention “endocrine disruptors.” Sounds like something foreign and insignificant. Well, the endocrine system turns out to be a hugely busy system in our bodies, one well worth looking into. When we start to understand how important this system is, we might start to pay attention to how we are damaging it with endocrine disrupting chemicals, because it is so easy to stop causing harm when we understand what the harm is, and so difficult, if not impossible, when we remain oblivious.

Information about endocrine disruptors:

The Environmental Protection Agency‘s Endocrine Disruptor Screening Program (EDSP): What are Endocrine Disruptors?, with a nice illustration.

The Natural Resources Defense Council: Endocrine Disruptors

Note: not listed on these pages is the fact that most fragrances contain endocrine disrupting chemicals. That also means everything with fragrance in it, like personal care, laundry and cleaning products.

Environmental Health News: Estrogen mimics at low doses change how brain cells manage dopamine:

For the first time, scientists find that extremely low levels of some types of environmental estrogens disrupt specialized brain cells and their ability to regulate brain chemistry. All of the EEs tested changed the way cells released and reabsorbed dopamine, an important chemical messenger that governs movement and pleasure.

[...]

If the observations found in this study using brain cells also occur in the brains of animals and people, the implications are alarming. Specifically, chemicals common in the products, air, water and food are potentially capable of profoundly altering brain chemistry at extremely low levels; levels that most humans and many animals are exposed to on a daily basis.

New York Times: Child Obesity Is Linked to Chemicals in Plastics (and fragrances):

The chemicals in question are called phthalates, which are used to to make plastics pliable and in personal care products. Phthalates, which are absorbed into the body, are a type of endocrine disruptor — chemicals that affect glands and hormones that regulate many bodily functions. They have raised concerns as possible carcinogens for more than a decade, but attention over their role in obesity is relatively recent.

CBC Documentaries: The Disappearing Male (includes full length film):

The Disappearing Male is about one of the most important, and least publicized, issues facing the human species: the toxic threat to the male reproductive system.

The last few decades have seen steady and dramatic increases in the incidence of boys and young men suffering from genital deformities, low sperm count, sperm abnormalities and testicular cancer.

At the same time, boys are now far more at risk of suffering from ADHD, autism, Tourette’s syndrome, cerebral palsy, and dyslexia.

The Disappearing Male takes a close and disturbing look at what many doctors and researchers now suspect are responsible for many of these problems: a class of common chemicals that are ubiquitous in our world.

Found in everything from shampoo, sunglasses, meat and dairy products, carpet, cosmetics and baby bottles, they are called “hormone mimicking” or “endocrine disrupting” chemicals and they may be starting to damage the most basic building blocks of human development.

Research: Sources of endocrine-disrupting chemicals in urban wastewater, Oakland, CA.

Synthetic endocrine-disrupting chemicals (EDCs) have been found in surface waters throughout the United States, and are known to enter waterways via discharge from wastewater treatment plants (WWTPs). Studies addressing EDCs in wastewater do not examine their specific sources upstream of WWTPs. Presented here are results of a pilot study of potential sources of selected EDCs within an urban wastewater service area. Twenty-one wastewater samples were collected from a range of sites, including 16 residential, commercial, or industrial samples, and five samples from influent and effluent streams at the WWTP. Samples were analyzed for the following known and suspected EDCs: five phthalates, bisphenol A (BPA), triclosan, 4-nonylphenol (NP), and tris(2-chloroethyl) phosphate (TCEP), using well-established methods (EPA 625 and USGS O-1433-01). Twenty of 21 samples contained at least one EDC. Phthalates were widely detected; one or more phthalate compound was identified in 19 of 21 samples. Measurement of two phthalates in a field blank sample suggests that the accuracy of sample detections for these two compounds may be compromised by background contamination. Triclosan was detected in nine samples, BPA in five samples, and TCEP in four samples; NP was not detected. The results of this and future source-specific studies may be used to develop targeted pollution prevention strategies to reduce levels of EDCs in wastewater.

Presentation: Here’s an excellent presentation on atrazine, endocrine disruption, and lack of effective oversight or regulations: From Silent Spring to Silent Night, a talk by Prof. Tyrone Hayes, Department of Integrative Biology, University of California, Berkeley, given at Humphrey Institute in Minneapolis on March 23, 2007. Dr. Hayes is an authority on the effects of the pesticide atrazine on frogs, and is not popular with chemical companies for his views and proven research. Prof. Hayes website is atrazinelovers.org, and there are links to “Act Now!”

The Endocrine Disruption Exchange or TEDX on The Fossil Fuel Connection: Fuel for Thought and Motivation.

In 1991, an international group of experts stated, with confidence, that “Unless the environmental load of synthetic hormone disruptors is abated and controlled, large scale dysfunction at the population level is possible.”1 They could not perceive that within only ten years, a pandemic of endocrine-driven disorders would begin to emerge and increase rapidly across the northern hemisphere. Today, less than two decades later, hardly a family has not been touched by Attention Deficit Hyperactivity Disorder, autism, intelligence and behavioral problems, diabetes, obesity, childhood, pubertal and adult cancers, abnormal genitalia, infertility, Parkinson’s or Alzheimer’s Diseases. TEDX’s findings confirm that each of these disorders could in part be the result of prenatal exposure to chemicals called endocrine disruptors.

TEDX has also confirmed that the feed stocks for most endocrine disrupting chemicals are derived from the production of coal, oil, and natural gas. It is clear that endocrine disruption, like climate change, is a spin-off of society’s addiction to fossil fuels. Setting aside the effects of endocrine disruptors on infertility, and just considering their influence on intelligence and behavior alone, it is possible that hormone disruption could pose a more imminent threat to humankind than climate change. The urgency of the above conclusions provided the incentive for much of the work described on this website.

How much more do we need to know before we do the right thing?

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