Shampoo, Soap, and… Brain Changes? Study Links Everyday Products to Infant Development Harm

Phthalates during pregnancy may alter a baby’s metabolism and brain development by crossing the placenta and disrupting key biological processes.

A newly published study conducted by researchers from Emory University, the University of North Carolina at Chapel Hill, and Columbia University reveals that exposure to phthalates during pregnancy may impact a newborn’s metabolism and brain development.

Phthalates are a group of chemical compounds commonly used as plasticizers. They are found in a wide range of everyday products, including shampoos, soaps, detergents, and plastic containers used for food and beverages. Previous studies have shown that phthalates can disrupt hormone activity and have been linked to various health concerns in both mothers and their children.

This latest research, led by scientists at Emory’s Rollins School of Public Health and published in Nature Communications, is the first to provide direct evidence that prenatal exposure to phthalates can alter an infant’s metabolic profile at birth.

Main Takeaways

• Prenatal phthalate levels in the mother’s blood during pregnancy were associated with lower levels of key neurotransmitter precursors (related to tyrosine and tryptophan metabolism) important for brain development in the newborn’s blood soon after birth.
• Higher prenatal phthalate levels were also associated with biological changes linked to lower information processing (or attention) and excitability (or arousal) scores in newborns.
• These findings suggest that a mother’s exposure to phthalates during pregnancy may influence her newborn’s metabolism soon after birth. Furthermore, exposure to phthalates while babies are still in the uterus may also have lasting effects on infant brain development.

What The Experts Say

“This was the first study to demonstrate that a mother’s exposure to phthalates can impact their baby’s metabolome and also the first to show that these biological changes can impact newborn development. This is important because there is a common belief that the placenta protects the baby from a lot of harmful substances, but this study supports that phthalates are able to cross through the placenta and actually impact the baby’s biology before they are even born and negatively affect their development over time,” said Susan Hoffman, PhD, study first author and recent graduate of the Epidemiology PhD program at the Rollins School of Public Health.

“We are seeing that once pregnant women are exposed to phthalates, these chemicals not only enter their body and disrupt maternal metabolism, but these exposures also impact the metabolism and neurobehavioral functioning of newborns. And we found these substances are staying with them in the body after they are born, as we did see some indication of a biological disruption occurring among the newborn babies that has a further impact on the neurodevelopment system,” says Donghai Liang, PhD, study lead author and associate professor of environmental health at the Rollins School of Public Health.

Reference: “Impact of prenatal phthalate exposure on newborn metabolome and infant neurodevelopment” by Susan S. Hoffman, Ziyin Tang, Anne Dunlop, Patricia A. Brennan, Thompson Huynh, Stephanie M. Eick, Dana B. Barr, Blake Rushing, Susan L. McRitchie, Susan Sumner, Kaitlin R. Taibl, Youran Tan, Parinya Panuwet, Grace E. Lee, Jasmin Eatman, Elizabeth J. Corwin, P. Barry Ryan, Dean P. Jones and Donghai Liang, 2 April 2025, Nature Communications.
DOI: 10.1038/s41467-025-57273-z