Dear EarthTalk: What are endocrine disruptors? How do they make their way into my body? What can I do to avoid them?
—Jo McGovern, Albany, NY
The endocrine system controls the various functions of cells, tissues and organs in our bodies through the secretion of hormones. The major glands that regulate the flow of these hormones include the pituitary, thyroid, parathyroid, and adrenal glands, as well as the pancreas and reproductive glands (ovaries in women, testicles in men). A properly functioning system ensures optimum mood, growth, development, metabolism, sexual function and reproduction. Endocrine disruptors are chemicals that mimic or block the action of natural hormones.
According to the Environmental Working Group (EWG), there is no end to the tricks that endocrine disruptors can play on our bodies. These chemicals can increase the production of certain hormones, decrease the production of others, turn one hormone into another, compete with essential nutrients and more.
Some 80 million pounds of atrazine, an herbicide named on EWG’s Dirty Dozen List of Endocrine Disruptors, are applied in the U.S. each year. A 2010 University of California (UC) Berkeley study found that atrazine-exposed male amphibians were feminized as a result. Ten percent of those exposed developed into females that copulated with unexposed males and produced viable eggs. “Given the overwhelming evidence of unacceptable risk, I’m quite frankly surprised that atrazine is even still in use,” said Dr. Tyrone Hayes, professor of Integrative Biology at UC Berkeley and the study’s lead author.
Roundup Reduces Testosterone
Monsanto’s Roundup, a trade name for glyphosate and the most widely used herbicide in the U.S. with 250 million pounds sprayed each year, was also recently found to have hormone disrupting capabilities. Studies released in 2015 determined that Roundup decreased levels of progesterone and corticosterone, a steroid hormone produced in the adrenal glands. An earlier study determined that even at lower, “non-toxic” exposure levels, Roundup reduced testosterone levels. Recently it was announced that the U.S. Environmental Protection Agency (EPA) will analyze the impacts of atrazine and glyphosate on 1,500 endangered plants and animals under the terms of a settlement reached with the Center for Biological Diversity (CBD). “This settlement is the first step to reining in the widespread use of dangerous pesticides that are harming both wildlife and people,” said Brett Hartl, CBD’s endangered species policy director.
Buying organic produce and drinking filtered water can reduce your exposure to hormone-disrupting herbicides and pesticides. Another good reason to install a water filter is to remove perchlorate, a chemical that is also named on EWG’s Dirty Dozen list. A 2010 study found that, in pharmacologic doses, perchlorate inhibits iodine uptake, an element needed for the production of thyroid hormones. The findings were alarming as adequate iodine intake is essential for normal neurodevelopment in infancy and childhood. While further research is needed to determine the impacts of perchlorate in the environment, the American Thyroid Association recommends that women who are planning a pregnancy or who are pregnant ingest 150 mg of iodine daily to ensure adequate iodine nutrition and to overcome the potential adverse effects of perchlorate exposure.
Conscious Consumers to the Rescue
While it may be frightening to think about all the potential exposures to endocrine disruptors around us today, purchasing environmentally-conscious, natural-based products for you, your family and your home; eating organic, fresh, unpackaged foods and drinking filtered water from a glass container are simple ways to help keep your hormones and endocrine system in balance.