Actress Kristen Chenoweth loves her beauty products, but she won’t be wearing a certain brand of eyelash extensions anymore. A year ago, the Emmy-award-winning actress discovered she had an allergy to formaldehyde, which was in the glue used to attach the lashes and caused her baby blues to swell half-shut.

Turns out “dead people’s juice,” as Chenoweth dubbed it, can be found in a variety of beauty products, even though the U.S. government declared it a carcinogen last year.

And formaldehyde is not the only ingredient that seems best left to Morticia Addams’ compact. Many cosmetics, shampoos and body washes contain a laundry list of potentially dangerous chemicals, including 1,4-dioxane, which has been linked to cancer in animals, and phthalates, parabens and triclosan, all known endocrine disruptors which can alter the way hormones behave in the body.

The majority of cosmetic ingredients are not federally regulated. That leaves consumers on their own to figure out the safety of products. “The vast majority of ingredients in cosmetics have never been assessed for safety by any public body,” says Janet Nudelman, director of program and policy at the Breast Cancer Fund.

The situation got a little bit better last August when health and beauty powerhouse Johnson & Johnson announced they will no longer put formaldehyde or other questionable chemicals in their products, even though scientists with the company say trace amounts of these toxins in products are not harmful.

How Much Is Too Much?

The average woman uses at least 10 products a day, raising the chances those trace amounts will add up. In addition, scientists say, some chemicals can do harm at very low levels. One example is endocrine disruptors, which mimic reproductive hormones, and have been linked to birth defects and breast cancer.

“You don’t need a lot of something acting like testosterone or estrogen to mess things up, especially in something as vulnerable as a developing fetus,” says Laurel Standley, a chemical researcher who studies endocrine disruptors.

Standley and other experts say there’s no foolproof method for avoiding toxic chemicals in personal care products. But they do offer some tips to make the job more manageable. Use Fewer Products: In one study in Environmental Health Perspectives, consumers who used a surface cleaner, tub and tile cleaner, laundry detergent, bar soap, shampoo, conditioner, facial cleanser, lotion and toothpaste—a plausible array of products—would expose themselves to 19 potentially toxic chemical compounds. Robin Dodson, a researcher at the Silent Spring Institute, advises people to make cleaners instead. “I tell people to clean like your grandmother,” she says. “Stick with water, baking soda and vinegar.”

Go Fragrance-Free: Synthetic fragrances can have dozens, even hundreds, of different chemicals mixed together, but consumers are never told what’s in the mix. Opt for “fragrance-free” products (while you’re at it, choose “dye-free” as well) or look for the words “plant-based fragrance” on the label.

Avoid Antimicrobials: These products contain triclosan and triclocarbans, both hormone disrupters. They’re marketed as germ fighters, but don’t work much better than soap and water, according to the Centers for Disease Control and Preven-tion. Antimicrobials, which can be found in everything from cutting boards to towels to liquid hand soaps, are regulated compounds, so they are easy to avoid.

Steer Clear of Formaldehyde: This cancer-causing agent can be found in certain brands of nail polish and hair-straightening products like the Brazilian Blowout brand—even those labeled formaldehyde-free have been shown to have the substance. Look for these ingredients on labels: DMDM hydantoin, diazolidi-nyl urea, imidazolidinyl urea, methenamine or quarternium-15.

Keep an Eye Out for the Two Ps: Parabens, preservatives, and phthalates, plastic additives, are both endocrine disrupters. These days it’s possible to find products labeled paraben-free and phthalate-free, but in the EHP study, researchers found that even some alternative products still contained derivatives of these compounds. Look out for methylparaben, ethylparaben and butylparaben as well as dicyclohexyl phthalate (DCP), diisononyl phthalate (DINP) and di-n-propyl phthalate (DPP).

Cover Up for Sun Protection: Wear a hat and tightly woven fabrics for sun protection. Sunscreens, even alternative ones, can contain chemicals such as cyclosiloxane, an endocrine disruptor.

Remember Green Isn’t Always Green: Terms like “green,” “botanical” and “all natural” are unregulated, so don’t be seduced by such labeling. Experts also recommend avoiding products that use essential oils made from lavender and tea trees, which, while fine in their original plant form, can act as endocrine disrupters when they are made into concentrated oils. “People think they’re safe because they’re natural,” Standley says. “But that’s not necessarily the case.”

Use Databases: The Environmental Working Group and the Good Guide both have online databases that rank beauty, cleaning and other products based on the safety of their ingredients. Go to ewg.org/skindeep or goodguide.com.•