Photo courtesy of Lillie Thompson


6 Common Toxic Chemicals—and
How to Avoid Them

Six of the Most Common Endocrine Disruptors—and How to Avoid Them

To follow the news is to know that there are chemicals in our waterways and carcinogens in our food supply. But what and where and how much? That’s where things get murky. Which is why we tapped Nneka Leiba, the director of healthy living science at the Environmental Working Group. In her monthly column, Leiba answers our most pressing concerns about toxicity, the environment, and the health of the planet. Got a question for her? You can send it to [email protected].

You’re exposed to hormone-disrupting chemicals every day, just about everywhere.

Endocrine-disrupting chemicals can interfere with the normal function of our delicate hormone system and play endless tricks on our body. These chemicals can increase the production of certain hormones and decrease the production of others. Some endocrine disruptors imitate hormones or turn one hormone into another and interfere with their signaling. Studies have linked these chemicals to cancer, lowered sperm count, lowered IQ, thyroid disease, birth defects, and other developmental disorders. Given that our hormones are critically important for proper growth and development, babies and children are at the greatest risk for adverse effects.

It’s hard to escape exposure to hormone-disrupting chemicals. These substances are found in plastic goods, personal-care products, household cleaners, fragrance, food and food packaging, toys, furniture, electronics, agricultural pesticides, and our drinking water. But you can minimize your exposure by making a few simple changes.

In my last column, I discussed six of the most common hormone disruptors. Here are six more—not to scare you, but to teach you how to avoid them.


Dioxins form during many industrial processes, including the combustion of industrial and domestic waste. These toxic chemicals can disrupt the delicate ways that both male and female sex hormones function in the body.

Dioxins accumulate in the food chain, mainly in animals’ fatty tissues. The higher an animal is on the food chain, the higher the concentration of dioxins in its body. The vast majority of human exposure is through food from animals, mainly meat, fish, eggs, and dairy products.

Dioxins are powerful carcinogens that can also affect the immune and reproductive systems. Research has shown that exposure to low levels of dioxins in the womb and early in life can both permanently affect sperm quality and lower the sperm count in men during their prime reproductive years.

How to reduce your exposure:

  • It is pretty difficult to completely avoid dioxins, since the ongoing industrial release of dioxins has meant that the American food supply is widely contaminated. But vegans are at an advantage here—try cutting down on food products that include meat, fish, milk, eggs, and butter, as these are most likely to be contaminated.


Lead is a potent neurotoxin, and there is no safe level of exposure, especially for children. Lead harms almost every organ system in the body and can cause serious, lifelong, and irreversible neurological deficits. Exposure to lead has been linked to an array of health effects, including permanent brain damage, lowered IQ, miscarriage, premature birth, and nervous system problems. But few people realize that another effect lead can have on your body is to disrupt your hormones. In animals, lead has been found to lower the levels of sex hormones. Research has also shown that it can disrupt the hormone signaling that regulates the body’s major stress system, called the HPA axis.

How to reduce your exposure:

  • Keep your home clean and well maintained. Crumbling old paint is a major source of lead exposure, so get rid of it—carefully.

  • Invest in a good water filter. Choose one that is certified to remove lead to reduce your exposure to lead in drinking water.

  • If you suspect that your tap water contains lead, you can get it tested. This is particularly important if you have lead-based water lines leading to your house, if your local water company has detected lead in water your neighborhood, or if you drink water from a private well and your local public health department detects lead in well water in your area.


Arsenic is a natural element in the earth’s crust. It can be found in water, air, and soil. But it is also a known human carcinogen that’s in our food and drinking water.

Rice is a leading source of arsenic exposure. As rice plants grow, they absorb arsenic from the soil. Both organically grown and conventional rice can be contaminated with arsenic.

If you eat enough arsenic, it can kill you outright. In small amounts, arsenic can cause skin, bladder, and lung cancer. Arsenic can also mess with our hormones and interfere with how our bodies process sugars and carbohydrates. As a result, it may cause weight gain or loss, protein wasting, and insulin resistance, which can lead to diabetes.

How to reduce your exposure:

  • Limit your consumption of rice and rice-based ingredients.

  • Look for alternatives to rice-based processed foods, such as breakfast cereals, rice flour, rice pasta, rice cakes, and rice crackers.

  • Check your drinking water. You can reduce your exposure by using a water filter that lowers arsenic levels.


Mercury, a naturally occurring but highly toxic heavy metal, gets into the air and the oceans primarily though the burning of coal. Eventually, it can end up on your plate in the form of mercury-contaminated seafood.

Mercury exposure can damage the nervous system, which can result in headaches, fatigue, difficulty with memory and concentration, poor coordination, and neuropathy. According to the World Health Organization, it is also linked to kidney damage, skin rashes, skin discoloration and scarring, as well as a reduction in the skin’s resistance to infections.

Pregnant women are most at risk from the toxic effects of mercury, since it is known to concentrate in the fetal brain and can interfere with brain development.

How to reduce your exposure:

  • Consider the seafood you consume. Use EWG’s Seafood Calculator to choose the best options for fish and shellfish that are high in omega-3 fatty acids and low in mercury.

  • Choose wild-caught fish over farm-raised fish.

Organophosphate Pesticides

Organophosphates are nerve agents the Nazis produced in huge quantities for chemical warfare during World War II (but they were never used). After the war ended, American scientists used the same chemistry to develop pesticides that target the nervous systems of insects. Despite many studies linking organophosphate exposure to effects on brain development, behavior, and fertility, they are still among the more common pesticides in use today.

A few of the many ways organophosphates can affect the body include interfering with the way testosterone communicates with cells, lowering testosterone, and altering thyroid hormone levels.

How to reduce your exposure:

Glycol Ethers

Glycol ethers, such as ethylene glycol, are commonly used solvents in some water-based paints and finishes. These chemicals are also found in some cleaning products, brake fluid, and cosmetics. The European Union says some of these chemicals “may damage fertility or the unborn child.” Studies of painters have linked exposure to certain glycol ethers to blood abnormalities and lower sperm counts.

Children exposed to glycol ethers from paint in their bedrooms had substantially more asthma and allergies. In addition to being a respiratory irritant, ethylene glycol can cause headaches and nausea as well as developmental problems.

How to reduce your exposure:

  • Avoid household products with ingredients such as 2-butoxyethanol (EGBE) and methoxydiglycol (DEGME) by searching EWG’s Guide to Healthy Cleaning.

  • Consider making your own cleaning products. Common kitchen ingredients like vinegar, lemons, and baking soda can make a good homemade cleaner. Here is a handy guide to what not to mix.

As the director of healthy living science at the Environmental Working Group, Nneka Leiba, MPhil, MPH, translates complicated scientific topics, particularly ones dealing with the effects of everyday chemical exposures on our health, into easily accessible tips and advice. Leiba has become an expert in a wide range of issues, including the safety of ingredients in cosmetics and other consumer products, and drinking water quality. She earned graduate degrees in zoology and public health from the University of the West Indies and Johns Hopkins University, respectively.