When the United Nations comes out with a report calling something a "global health threat," we should probably be more than a little concerned. And that's exactly what happened in early 2013 when the World Health Organization and the UN Environment Programme applied the term to a class of chemicals known as endocrine disruptors. The reason: A growing body of research is linking these potent chemicals, which interfere with the endocrine system that regulates your hormones, to global rates of chronic disease and infertility.
"Never has there been a time in history that the disease burden of the human population is predominantly chronic disease, not communicable or infectious disease," Thomas Zoeller, PhD, professor of biology at the University of Massachusetts, Amherst, and a coauthor of the report, told us at the time. "We can't prove that this is related to endocrine-disrupting chemicals, but we can't continue to deny their impact."
Now the nonprofit Environmental Working Group (EWG) and the Keep a Breast Foundation are sounding alarm bells about the health threat of these chemicals. Of the roughly 80,000 chemicals used in everyday goods, 1,300 or so are considered endocrine disruptors, also called hormone disruptors. The nonprofits just released a report outlining the "Dirty Dozen," a list of endocrine disruptors that highlights the worst of the worst--and the ones you're most likely exposed to every day. Here's how to avoid them:
What it does: Perhaps the most widely studied endocrine disruptor on the market, BPA actually started out in the 1930s as a synthetic estrogen given to women. So it's no surprise that this hormonal chemical has been found to act like estrogen, with current exposure levels leading to things like decreased sperm production in men, early puberty in girls, and fertility problems in both genders, or that animal studies have linked it to greater chances of miscarriage. BPA also interferes with metabolic hormones and plays a role in heart disease, obesity, and diabetes.
Where it's found: BPA is found in the linings of food cans, and it's used as a coating on receipts. The chemical is still used in some plastic products and as a flame retardant, as well, but thanks to the lack of laws requiring companies to disclose how BPA is being used, it's impossible to know all the places where the nearly 3 billion pounds of the chemical produced each year wind up.
Easiest way to avoid it: Opt for fresh, frozen, or homemade versions of your favorite canned foods. You can also limit additional exposures by rejecting unnecessary receipts when shopping.
What they do: Dioxins and dioxinlike compounds like PCBs and the pesticide DDT are known to cause cancer, but they're also considered one of the most toxic classes of chemicals known to man. Among their hormone-related effects: decreased fertility, diabetes, endometriosis, immune system problems, lowered testosterone levels, miscarriages, and reduced sperm counts and quality.
Where they're found: Municipal waste incineration produces large quantities, but chemical bleaching of paper and wood pulp accounts for huge quantities in the air and water. Dioxins build up in the fatty tissues of animals and are very widespread in the food supply.
Easiest way to avoid them: Reduce your consumption of fatty meat and dairy products.
What it does: Most of the research on atrazine's hormone-mimicking effects has been conducted in fish and frogs. Like a freaky science-fiction plot, the chemical causes male fish and frogs to turn into females. Research into humans, however, has shown that the pesticide increases the activity of genes that cause infertility.
Where it's found: Atrazine is the second most widely used herbicide in the United States (behind glyphosate, the active ingredient in Roundup), according to the Environmental Protection Agency (EPA), and 86 percent of it is applied to corn.
Easiest way to avoid it: Go organic! Organic farmers are prohibited from using toxic synthetic herbicides like atrazine. And eat less meat. Despite corn's reputation as serving as the building block for numerous processed-food ingredients, 80 percent of U.S.-grown corn is sold both domestically and internationally as animal feed, according to the National Corn Growers Association. Eating tons of factory-farmed meat simply increases the demand for atrazine among corn growers
What they do: Like BPA, phthalates have come under a lot of scrutiny in recent years, after studies revealed that boys born of women with high phthalate exposures suffered from abnormalities in their genitals. The chemicals interfere with testosterone and estradiol, a hormone that affects breast development. Studies have found that women who develop breast cancer have higher levels of certain types of phthalates than women who are cancer free.
Where they're found: Phthalates are used in a vast number of consumer products: flooring, shower curtains, synthetic leather, and other products made with PVC vinyl, where phthalates are used to keep the plastic flexible; in any product with a synthetic fragrance, where phthalates are used to keep the scent from dissipating; and nail polishes, paints, and furniture finishes, where phthalates keep the materials from chipping. They've also been detected in some plastic cling wraps and food containers, as well as pesticides.
Easiest ways to avoid them: Avoid anything with a synthetic fragrance, say "NO!" to vinyl products, and always store your food in glass, ceramic, or stainless steel containers.
What it does: Perchlorate can interfere with your thyroid, the gland that regulates the hormones that regulate your metabolism. The chemical, a component of rocket fuel, impairs your thyroid's ability to take up iodine, which the gland needs to function properly.
Where it's found: Perchlorate contamination exists anywhere rockets were tested, made, or taken apart, and it's used in fireworks and safety flares. It washes out of soil and gets into groundwater, but no one knows how long this persistent toxic chemical takes to break down. You're most likely exposed to perchlorate through food; eggs, dairy products, fruits and vegetables contain the highest levels. Water is another source of exposure for people living in certain areas. The EPA estimates that 20 million Americans live in areas with excessive levels of the contaminant in their drinking water.
Easiest way to avoid it: The chemical is nearly impossible to avoid in food, and the water filters that remove it are expensive. EWG recommends getting good amounts of iodine, which can boost your thyroid function even in the presence of perchlorate. Iodized salt is a good source, as are seafood, kelp, and grass-fed dairy products.
What they do: These toxic, ubiquitous chemicals are most known for their impact on the thyroid and on female infertility. Because thyroid hormones also have an impact on your brain, one class of flame retardants, known as PBDEs, is thought to affect the IQ levels in children, which is why many chemicals in this class have been banned or are being gradually phased out. However, the replacements being used are just as toxic and exhibit the same biological activity as organophosphate pesticides.
Where they're found: Furniture, carpet padding, and even baby nursing pillows contain them. Assume that anything in your home--and your office and your car--that contains polyurethane foam also contains flame retardants. Other major exposure sources include electronics: TVs, computers, cellphones, and video game consoles.
Easiest way to avoid them: Dust and vacuum frequently. It's nearly impossible to avoid flame retardants, given their widespread use, so cleaning is your best defense. Flame retardants bind to dust as the furniture, car-seat padding, and electronics in which they're used break down.
What it does: Despite the long list of health problems already associated with lead, researchers are uncovering still more, including the fact that lead interferes with the hormones that regulate your stress levels, according to EWG.
Where it's found: Lead-based paint remains the general public's largest source of exposure to this toxic metal. But it also winds up in drinking water from old pipes and even new brass or chrome faucet filters (including, thanks to a regulatory loophole, those labeled "lead free"). See 6 Sneaky Sources of Lead for other unexpected places this heavy metal lurks.
Easiest ways to avoid it: Get a lead-removing water filter and eat a healthy diet. According to EWG, research has shown that people who eat a healthy diet absorb less lead. But if you are renovating an older home, it's imperative that you call a lead-remediation professional, which you can find here.
What it does: While arsenic is best known for its ability to cause cancers of the skin, bladder, and lung, there is no other element or chemical known to cause as many health problems as arsenic can, according to the Dartmouth Toxic Metals Superfund Research Program, and those include endocrine problems. Arsenic has been found to interfere with receptors for estrogen, progesterone, and testosterone, including hormones that regulate your metabolism and your immune system.
Where it's found: The Centers for Disease Control says that food and water are your main exposure sources; arsenic was historically used in pesticides and it exists naturally in soil. Recent tests from Consumer Reports have found high levels of the metal in rice and apple and grape juices, and the Johns Hopkins School of Public Health has found high levels in factory-farmed chicken. Though they're gradually being phased out, arsenic-based drugs are added to chicken feed in nonorganic chicken houses.
Easiest ways to avoid it: Water filters certified to remove arsenic can get it out of your water. Avoiding it in food is harder, since there's no way to know which foods contain high levels. Consumer Reports recommends limiting your rice consumption to two servings per week and varying your grains, along with eating whole fruits instead of drinking fruit juices. And stick with organic chicken, which are raised on arsenic-free feed.
What it does: Another metal that does double the damage, mercury is a potent neurotoxin that impairs children's IQ levels. But EWG found that it also binds to a hormone that regulates women's menstrual cycles and ovulation, and it damages cells in the pancreas that produce insulin, the hormone that regulates your blood sugar levels.
Where it's found: Primarily found in seafood, mercury winds up in the environment from industrial sources, the largest of which are coal-fired power plants.
Easiest way to avoid it: Stick with low-mercury seafood choices, such as wild Alaskan salmon and farmed trout, along with seafood that's low on the food chain, such as sardines and anchovies. In general, the smaller the fish, the less contaminated it is.
What they do: PFCs--which you'll recognize through trade names as Teflon and Stainmaster--have been studied most for their impact on thyroid function and their links to hypothyroidism. The chemicals are also thought to cause infertility in both men and women. One possible reason for that, at least in women, comes from recent research in animals, which suggests that the chemicals inhibit a woman's ovaries from producing eggs.
Where they're found: PFCs are used to make your pots and pans nonstick and your clothes, upholstery fabric, carpets, backpacks, and coats water- and stain-repellent. The chemicals are also used to repel grease in food packaging like pizza boxes, fast-food wrappers, microwave popcorn bags, and pet-food bags.
Easiest ways to avoid them: Avoid all of the above! Keep an eye out for anything that utilizes "Gore-Tex," "Stainmaster," or "Teflon," all trademarks for chemical mixtures that contain PFCs. And call manufacturers to question them about their use of PFCs whenever they advertise products as water repellent; some have switched to polyurethane coatings, which pose fewer health problems.
What they do: Breakdown products of these neurotoxic insecticides have been associated with lower levels of testosterone and other sex hormones, according to the Pesticide Action Network North America. Mothers exposed to organophosphates while pregnant also experience increased levels of cortisol (a stress hormone), which can increase the risks for miscarriage, preeclampsia, and developmental delays for the child.
Where they're found: Organophosphates are one of the most commonly used classes of insecticides in the U.S. and are found on a wide variety of crops.
Easiest way to avoid them: Go organic! Organic farmers are prohibited from using synthetic pesticides like organophosphates on their fields.
What they do: These chemicals are associated with numerous health problems, but with regard to hormones, they're bad for guys' swimmers. The chemicals cause low sperm motility.
Where they're found: Glycol ethers are solvents used in a wide variety of industrial applications. But you're most likely to encounter them via dry-cleaning services and in personal care products and cleaners.
Easiest ways to avoid them: Avoid having clothes dry-cleaned (most fabrics can just as easily be hand-washed) and make your own cleaning products (here are eight of our favorite recipes). Also, search EWG's Skin Deep Database to find personal care products free of these harmful ingredients.
View the entire endocrine disruptors list at ewg.org/research/dirty-dozen-list-endocrine-disruptors.