Study Finds Toxic Nail-Polish Chemicals in Women’s Bodies

According to a new study from Duke University and the Environmental Working Group (EWG), painting your nails doesn’t just give it a nice coat of color— it also may release an endocrine-disrupting chemical into the body.

Nail-polish chemicals in women’s bodies

The study found that women who painted their nails with nail products including triphenyl phosphate (TPHP) had a metabolite of the chemical in their bodies 10 to 14 hours later. Their levels of diphenyl phosphate (DPHP), which forms when the body metabolizes TPHP, increased by nearly sevenfold, according to a news release.

“It is very troubling that nail polish being marketed to women and teenage girls contains a suspected endocrine disruptor,” study co-author Johanna Congleton, Ph.D., MSPH, a senior scientist at EWG, said in a news release. “It is even more troubling to learn that their bodies absorb this chemical relatively quickly after they apply a coat of polish.”

For their study, researchers tested 10 polishes for TPHP and discovered the chemical in eight— two of the eight did not included TPHP in the ingredient label.

More than 1,500 nail products— including those made by Sally Hansen, OPI and Wet N Wild— contain TPHP, according to EWG’s Skin Deep cosmetics database.

According to researchers, previous laboratory studies have shown that TPHP exposure causes endocrine disruption and animal studies found the chemical caused reproductive and developmental problems. More recently, a study found that TPHP may contribute to weight gain and obesity.

TPHP is likely used as a plasticizer in nail polish to make it more flexible and durable, researchers noted. It’s been used in plastics manufacturing and as a fire retardant in foam furniture.

“It is possible that TPHP is now being used in nail polish as a replacement for phthalates, which also have endocrine-disrupting properties and are toxic to the reproductive system,” principal investigator Heather Stapleton, Ph.D., associate professor at Duke University, said in the news release. “However, it’s not clear that TPHP is the better alternative. There is growing evidence suggesting that TPHP may affect hormone regulation, metabolism, reproduction and development.”

On Monday, EWG launched a consumer petition to stop popular nail brands from using TPHP.