For centuries, people used cosmetics laced with mercury to eliminate freckles and blemishes. In the Renaissance, for example, the liquid metal was used as a facial peel to smooth small pox scars. “The trouble is, mercury exposure can cause potentially deadly health problems,” says Consumer Reports chief medical adviser Marvin M. Lipman, M.D. In 1973 the Food and Drug Administration banned cosmetics with more than a trace amount of the metal: 1 part per million (ppm).

Yet, the FDA recently warned consumers that cosmetics with high mercury levels are still being sold. In a statement, the FDA says, “The products are usually marketed as skin lighteners and anti-aging treatments that remove age spots, freckles, blemishes, and wrinkles. Adolescents may use these products as acne treatments.” The FDA notes that marketers of these products often target Asian, African, Latino, and Middle Eastern consumers.

Here’s what you need to know about mercury in skin products.  

The Risks

Exposure to mercury can cause gastrointestinal problems and kidney damage. “Mercury can also build up in the brain and affect the central nervous system, producing symptoms that include tremors, memory loss, and weakness,” says Orly Avitzur, M.D., a neurologist and Consumer Reports' medical director.

“The group we are most concerned about when it comes to mercury exposure is pregnant women,” says medical toxicologist Jeffrey Brent, M.D., Ph.D., a distinguished clinical professor of medicine at the University of Colorado School of Medicine in Aurora. “We know that fetuses are far more sensitive to mercury than adults, and you can get very severe injury to the fetus without the mother showing any symptoms at all,” Brent says. For example, fetuses that are exposed to mercury can be born with multiple congenital abnormalities, including severe physical deformities, a type of cerebral palsy, and other brain disorders.

Mercury in cosmetics is particularly worrisome because the skin is extremely efficient at absorbing the chemical, Lipman says. According to a 2016 study in the International Journal of Hygiene and Environmental Health, an adult can potentially absorb up to 450 mcg of mercury from a single application of a product containing 10,000 ppm of mercury. That's 90 times the amount in a 4-oz Mediterranean swordfish steak. (Learn how to choose the right fish to lower mercury risk exposure.)

Simply being close to mercury-laden creams or soaps might be harmful, even if you don't apply them to your skin. “Research shows that products containing mercury can give off mercury vapors that can be absorbed through the lungs,” says Michael Hansen, Ph.D., a senior scientist at Consumer Reports.

Avoiding Cosmetics Containing Mercury

Mercury doesn’t have a smell, taste, or particular color, Brent says, so you can’t determine whether a product contains the metal without conducting a thorough chemical analysis. But there are steps you can take to help you steer clear of cosmetics that might contain it.  

Read the label of any cosmetic product you buy. Skip it if the list of ingredients includes mercury or any of these synonyms: calomel, mercurous chloride, mercuric, and mercurio.

Be wary of imported products marketed as skin lighteners or anti-aging formulas. A 2014 study in the journal American Academy of Dermatology found mercury in 12 out of 367 “skin lightening” or “spot removal” products that researchers purchased online and in African and Caribbean groceries, ethnic markets, and other U.S. stores. All of the products were manufactured abroad or did not list a country of origin. (Overall, 6 percent, or 33 out of the 549 products the researchers purchased worldwide, contained mercury levels above 1,000 ppm.) In addition, earlier this year the FDA warned consumers not to purchase or use a Mexican-made skin whitening cream called Crema Piel De Seda (Silky Skin Cream) after lab tests revealed that it contained mercury.  

Skip any product that does not include an ingredients label. Federal law requires manufacturers to list ingredients on the labels of all cosmetics, according to the FDA, and a missing label may be a sign that a product is being marketed illegally.  

What to Do If a Product You Use Contains Mercury

If you suspect that a product you use contains mercury, stop using it immediately and get rid of it, Lipman says. But don’t throw it away in your household trash. Products containing mercury are considered “hazardous waste.” Seal the item in a plastic bag and check with your local waste district or trash collector about disposing of it correctly. Use the recycling locator on Earth911.com to find a mercury recycling center near you.

You can also report the product to the FDA.

If you are experiencing any symptoms of mercury poisoning, contact your health care provider. Symptoms of mercury exposure include anxiety; depression; drowsiness; fatigue; hair loss; inflamed gums; insomnia; irritability; memory loss; rash; tingling of the extremities, including the hands feet and lips; tremors; and weakness.