Girls may be starting puberty earlier due to chemical exposure: Study

Girls exposed to certain chemicals that are common ingredients in household products may be starting puberty comparatively early, a new study has found.

Substances of particular concern include musk ambrette — a fragrance used in some detergents, perfumes and personal care products — and a group of medications called cholinergic agonists, according to the study, published on Tuesday in Endocrinology.

These chemicals are all known as “hormone-disrupting” or “endocrine-disrupting” compounds, due to their tendency to block or interfere with hormone function in the body’s endocrine system.

To draw their conclusions, National Institutes of Health (NIH) researchers performed an initial screening of 10,000 environmental compounds and then studied the activities of select substances using lines of both rodent and human brain cells that control reproductive functions.

“Our team identified several substances that may contribute to early puberty in girls,” co-lead author Natalie Shaw, of the NIH’s National Institute of Environmental Health Sciences, said in a statement.

These compounds, Shaw and her colleagues found, were able to trigger certain receptors — proteins that bind to cell membranes and respond to stimuli — that play a key role in the puberty process.

The proteins of interest, called gonadotropin-releasing hormone receptor and the kisspeptin receptor, are located in the hypothalamus, the section of the brain that regulates hormones and related bodily functions.

The ability of compounds like musk ambrette to stimulate those receptors, Shaw explained, increases “the possibility that exposure may prematurely activate the reproductive access in children.”

Musk ambrette raised particular concern among the researchers due to its presence in personal care products. In addition, some rat studies have shown that it can cross the blood-brain barrier.

Children are less likely to come into contact with the cholinergic agonist medications in their daily lives, the scientists noted.

While Canadian and European regulators have already restricted musk ambrette use and the U.S. Food and Drug Administration removed the compound from its “generally recognized as safe” list, the compound remains widely available. 

“Out of an abundance of caution, it is important for parents to only use personal care products for their children that are federally regulated,” Shaw said.