Babies are exposed to a significantly wider range of “forever chemicals” in the womb than previously understood, according to research published today, , in Environmental Science & Technology. The study, led by Dr. Shelley H. Liu of the Icahn School of Medicine at Mount Sinai, reveals that current methods of assessing prenatal chemical exposure may be dramatically underestimating the extent to which infants are exposed to per- and polyfluoroalkyl substances (PFAS) before birth.
PFAS are a large group of man-made chemicals used in countless everyday products, including nonstick cookware, stain-resistant fabrics, food packaging, and firefighting foams. Their persistence in the environment and the human body has earned them the moniker “forever chemicals.” While the health effects of many PFAS are still being investigated, growing evidence links prenatal exposure to a range of developmental concerns, including low birth weight, preterm birth, altered immune responses, and metabolic changes.
The research team analyzed archived umbilical cord blood samples collected between and from 120 babies participating in the HOME Study in Cincinnati. What sets this study apart is its use of a novel, data science-driven approach and a non-targeted chemical analysis method. Traditional PFAS testing typically focuses on a limited number of well-known compounds. This new method, however, scans for hundreds to thousands of chemicals simultaneously, allowing researchers to detect a much broader spectrum of PFAS, including newer and less-studied substances.
“When we look more comprehensively, we see that babies are exposed to far more PFAS chemicals before birth than we previously realized—and some of the patterns we thought we understood may change,” explained Dr. Liu. The team identified 42 confirmed or tentatively identified PFAS chemicals in the cord blood samples, many of which are not routinely screened for in standard testing.
To quantify the overall PFAS burden, researchers developed “PFAS-omics burden scores” using a sophisticated statistical technique called item response theory. These scores provide a snapshot of a baby’s total PFAS exposure at the time of birth. Interestingly, when using this more comprehensive assessment, the researchers did not find differences in PFAS exposure between babies born to first-time mothers and those born to mothers who had previous pregnancies – a difference that had been observed in earlier studies using more limited PFAS panels.
This finding highlights the importance of using comprehensive testing methods. The study suggests that previous assessments may have missed significant exposures, leading to incomplete or inaccurate conclusions about risk factors. The American College of Obstetricians and Gynecologists has already identified reducing exposure to toxic environmental chemicals like PFAS as a “critical area of intervention,” underscoring the growing concern within the medical community.
Currently, PFAS exposure is not routinely measured in clinical practice, despite mounting evidence of its potential health impacts. However, this research offers a potential pathway toward more accurate exposure assessment. The newly developed method could eventually help clinicians identify individuals with higher exposure burdens, monitor at-risk populations more closely, and inform the development of preventive strategies.
“For now, this work helps lay the scientific foundation,” Dr. Liu said. “Our goal is to move toward earlier identification and prevention, especially during sensitive windows like pregnancy.”
The research team is now planning further studies to investigate whether higher cumulative PFAS exposure in early life is associated with adverse health outcomes. They also aim to explore the specific health effects of the newly identified and understudied PFAS chemicals found in cord blood and to refine tools for primary disease prevention. Future research will also focus on linking the PFAS-omics scores to the health outcomes of the study participants as they reach adolescence, providing valuable insights into the long-term consequences of prenatal PFAS exposure.
This research underscores the complex and widespread nature of PFAS exposure and the need for continued investigation into the potential health risks posed by these “forever chemicals.” A more complete understanding of prenatal PFAS exposure is essential for protecting child health and reducing preventable environmental risks.
