Exposure to certain chemicals found in common household products could cause girls to start menstruating earlier, a study has found.

According to the study, these substances include musk ambrette, a fragrance used in detergents, perfumes, soaps and other personal care products. A group of drugs called cholinergic agonists are also a cause of premature puberty, according to research published in Endocrinology.

Known as “hormone-disrupting” or “endocrine-disrupting” compounds, these substances block or interfere with the function of hormones in the body’s endocrine system.

Researchers at the US National Institutes of Health (NIH) conducted a preliminary screening of 10,000 environmental compounds and studied the activities of select substances using rodent and human brain cells that control reproductive functions.

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

Shaw and his colleagues found that these compounds activate certain receptors (proteins that attach to cell members and respond to stimuli) that play a role in the puberty process.

The proteins being studied, known as the gonadotropin-releasing hormone receptor and the kisspeptin receptor, are found in the hypothalamus, a part of the brain responsible for regulating hormones and managing a variety of bodily functions.

The ability of compounds such as musk ambrette to stimulate those receptors “raises the possibility that fertility in children may be activated prematurely,” Shaw explained.

Researchers have expressed concern about musk ambrette due to its widespread use in personal care products. Some studies on rats have shown that it can cross the blood-brain barrier.

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

Although children are less likely to receive cholinergic agonist medications daily, the scientists pointed out that musk ambrette is still widely available, despite bans in Canada and Europe and being removed from the U.S. FDA’s “generally recognized as safe” list.