Common Fragrance Ingredient May Be Linked to Early Puberty in Girls, Study Finds

The age at which girls enter puberty has been declining for decades, and a new study offers a potential explanation involving a synthetic compound found in numerous consumer products.

According to Dr. Natalie Shaw, a pediatric endocrinologist at the National Institute of Environmental Health Sciences in Durham, North Carolina, this is the first time researchers have investigated the effect of environmental chemicals on the brain in the context of early puberty.

Early puberty — before age 8 in girls and 9 in boys — is associated with long-term health risks, including breast cancer, heart disease, and diabetes, and can result in shorter adult height.

A May study from the Harvard T.H. Chan School of Public Health reported that 15.5% of girls had early periods, defined as before age 11, and 1.4% began menstruating before age 9.

Earlier theories have linked early puberty to factors like obesity, diet, socioeconomic status, and exposure to endocrine-disrupting chemicals such as phthalates.

Shaw, co-senior author of the new study, acknowledged a connection between excess weight and early puberty.

“I do think it plays a role,” she said, “but in my practice, it’s not just those who are overweight or obese who are having early puberty.”

While genetics influence puberty timing, a shift this rapid strongly suggests “100% environmental factors,” Shaw said, prompting researchers to search for common chemical exposures among children.

In examining over 10,000 licensed pharmaceuticals, environmental chemicals, and dietary supplements, researchers identified several compounds potentially linked to puberty onset.

One compound stood out for its likelihood of widespread exposure: musk ambrette.

Published in Endocrinology, the study found that musk ambrette — a synthetic fragrance compound — could bind to a receptor in the brain’s hypothalamus, prompting the release of GnRH, a hormone central to sexual development and the production of estrogen, testosterone, and progesterone.

Shaw noted that musk ambrette is often found in inexpensive or counterfeit fragrances and other scented personal care items.

It has also been detected in wastewater and in freshwater fish, indicating broader environmental presence.

To test its effects, researchers exposed both human hypothalamic cells and zebrafish larvae to musk ambrette and observed a rise in GnRH production in both models.

“This is just a first step,” Shaw said. Future studies will assess its effects in mammals like rodents and examine human blood levels of the compound.

Until more is known, Shaw recommends that parents scrutinize ingredient lists for musk ambrette in cosmetics, fragrances, and household items their children use.

Dr. Apisadaporn Thambundit, a pediatric endocrinologist and assistant clinical professor at UCLA, called the topic important but cautioned against drawing strong conclusions from this single study.

“I don’t think it’s strong enough to suggest anything that parents can do,” she said, adding she was surprised phthalates were not among the compounds identified.

Jasmine McDonald, associate professor of epidemiology at Columbia University’s Mailman School of Public Health, said the study’s strength lies in its design — starting with a biological mechanism, not a preconceived compound.

“As a first step, (the findings) are great,” she said.

However, McDonald added that it’s too early to consider regulation. Still, families could reduce their exposure by avoiding scented products.

“If you need a lotion, it can be scent-free,” she said. “In the shower, you can avoid scented body washes and shampoos.”