Prenatal exposure to chemicals in personal care products may speed puberty in girls

Some associations of altered pubertal timing in girls, but little evidence in boys.

Many personal care products contain chemicals that are known endocrine-disruptors. A new study shows that prenatal exposure to two common chemicals, diethyl phosphate and triclosan, may be linked to earlier puberty in girls.
Many personal care products contain chemicals that are known endocrine-disruptors. A new study shows that prenatal exposure to two common chemicals, diethyl phosphate and triclosan, may be linked to earlier puberty in girls.

Many previous studies have suggested that girls and possibly boys have been experiencing puberty at progressively younger ages. Puberty at an early age may lead to increased risk of mental illness, breast, and ovarian cancer in girls and testicular cancer in boys.

A new study by the UC Berkeley scientists has suggested that girls who are exposed to chemicals in personal care products before birth are more likely to hit puberty earlier.

For the study, scientists gathered the data as part of the Center for the Health Assessment of Mothers and Children of Salinas (CHAMACOS) study, which followed 338 children from before birth to adolescence. Their main objective was to determine how early environmental exposures affect childhood development.

Daughters of mothers who had higher levels of diethyl phthalate and triclosan in their bodies during pregnancy experienced puberty at younger ages. The same trend was not observed in boys.

Diethyl phthalate is often used as a stabilizer in fragrances and cosmetics. The antimicrobial agent triclosan — which the FDA banned from use in hand soap in 2017 because it was shown to be ineffective — is still used in some toothpastes.

Kim Harley, an associate adjunct professor in the School of Public Health said, “We know that some of the things we put on our bodies are getting into our bodies, either because they pass through the skin or we breathe them in or we inadvertently ingest them. We need to know how these chemicals are affecting our health.”

According to scientists, numerous synthetic substances in personal care products can meddle with normal hormones in our bodies, and studies have demonstrated that introduction to these chemicals can modify reproductive development in rats.

Chemicals that have been ensnared incorporate phthalates, which are frequently found in scented items like fragrances, cleansers, and shampoos; parabens, which are utilized as preservatives in cosmetics; and phenols, which incorporate triclosan.

For the CHAMACOS study, scientists recruited pregnant women living in the farm-working, primarily Latino communities of Central California’s Salinas Valley between 1999 and 2000. They measured concentrations of phthalates, parabens, and phenols in urine samples taken from mothers twice during pregnancy, and from children at the age of 9.

They then followed the growth of the children — 159 boys and 179 girls — between the ages of 9 and 13 to track the timing of developmental milestones marking different stages of puberty.

The vast majority — more than 90 percent — of urine samples of both mothers and children showed detectable concentrations of all three classes of chemicals, with the exception of triclosan which was present in approximately 70 percent of samples.

The researchers found that every time the concentrations of diethyl phthalate and triclosan in the mother’s urine doubled, the timing of developmental milestones in girls shifted approximately one month earlier. Girls who had higher concentrations of parabens in their urine at age 9 also experienced puberty at younger ages.

Though, it is still misty if the chemicals were causing the move, or if a young girl who reached puberty before were bound to begin utilizing individual consideration items at more youthful ages.

Harley said, “While more research is needed, people should be aware that there are chemicals in personal care products that may be disrupting the hormones in our bodies.”

“Consumers who are concerned about chemicals in personal care products can take practical steps to limit their exposure.”

The study is published in the journal Human Reproduction.