Study finds toxic chemical in nail polish

Women who paint their fingernails might be absorbing a toxic chemical, a new study published Monday found.

Researchers at Duke University and the Environmental Working Group (EWG) found evidence of a suspected endocrine-disrupting chemical widely used in popular nail polishes in the bodies of more than two-dozen women who participated in a biomonitoring study.

The study, published in Environment International, found that all women had a metabolite of triphenyl phosphate, or TPHP, in their bodies just 10 to 14 hours after painting their nails.  Their levels of diphenyl phosphate or DPHP, which forms when the body metabolizes TPHP, had increased nearly sevenfold.

EWG said laboratory studies have found that exposure to TPHP can cause endocrine or hormone disruption, which can lead to cancerous tumors and birth defects and other developmental disorders in unborn babies.

“It is very troubling that nail polish being marketed to women and teenage girls contains a suspected endocrine disruptor,” Johanna Congleton, a senior scientist at EWG and co-author of the Duke-EWG study, 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.”

According to EWG, more than 1,500 nail polishes contain TPHP.

In a statement Monday, the Personal Care Products Council’s Chief Scientist Beth Lange said there is no substance the Duke-EWG study and called its claims “alarming.”

“American consumers should not be concerned by new research that is speculative, misleading and does not use sound science to assess the safety of an ingredient, which has a long and well-documented history of safe use,” she said.

She went on to say that TPHP has been widely and safely used across many industries and sometimes an “extremely small amount” is used in nail polish as a way to increase its flexibility and durability.

Like all ingredients in cosmetic products, the council said TPHP must be safe for its intended use under current Food & Drug Administration regulations. The group said data from other biomonitoring studies have shown that TPHP is found in both men and women, contradicting EWG’s conclusion that its use in nail polish is an important contributor to TPHP exposure.

(This story was updated at 6:05 p.m. to include comments from the Personal Care Products Council.)