PFAS are man-made chemicals commonly found in water, food, and a wide range of everyday products. Often referred to as “forever chemicals,” many of these substances do not break down easily and can build up in the environment and inside the human body. Scientists are concerned that this persistence may interfere with normal development, including the formation of healthy bones.

“Adolescence is a key period for building strong bones, and achieving optimal bone mass during this time can reduce lifelong risks of fractures and osteoporosis,” said Jessie P. Buckley, Ph.D., M.P.H., of the UNC Gillings School of Global Public Health in Chapel Hill, N.C. “Our findings suggest reducing PFAS exposure during key developmental windows could support healthier bones throughout life.”

Study Tracks PFAS Levels and Bone Density

To explore this link, researchers analyzed blood samples from 218 adolescents who were part of a long-term pregnancy and birth cohort. PFAS levels were measured at multiple stages, including at delivery and at ages 3, 8, and 12 years old. Bone density was then assessed when participants reached age 12.

The study found that teens with higher levels of perfluorooctanoic acid (PFOA) in their blood had lower bone density in the forearm.

Timing and Gender Differences in PFAS Effects

For other PFAS compounds, the relationship with bone density varied depending on when exposure occurred. This suggests that certain stages of development may be more sensitive to these chemicals than others. The connection between PFAS levels and lower bone density was also stronger in females than in males.

“These findings add to growing evidence that PFAS exposure during early life may carry long-term health consequences, underscoring the importance of efforts to reduce contamination in drinking water and consumer products,” Buckley said.

Research Team and Funding

The study included researchers from several institutions, including Johns Hopkins Bloomberg School of Public Health, Brown University, the U.S. Centers for Disease Control and Prevention, the University of Cincinnati College of Medicine and Cincinnati Children’s Hospital, the University of Pennsylvania, Simon Fraser University, and The George Washington University Milken Institute School of Public Health.

Funding was provided by the National Institute of Environmental Health Sciences. The study, titled “Per- and Poly-fluoroalkyl Substances and Adolescent Bone Mineral Density: Assessing Periods of Susceptibility,” was published online.