New research from Mount Sinai has revealed that fetuses are likely exposed to significantly higher levels of harmful PFAS compounds—commonly referred to as “forever chemicals”—than previously understood. This groundbreaking study highlights the urgent need for enhanced monitoring and regulation of these toxic substances, particularly concerning their effects on vulnerable populations.
A Comprehensive Investigation into PFAS
Traditionally, testing of umbilical cord blood has focused on a limited number of PFAS compounds, such as PFOA and PFOS. However, a new study involving 120 samples of umbilical cord blood has broadened the scope of analysis, uncovering a staggering 42 different PFAS compounds. This expanded “non-targeted analysis” reveals that the total concentration of PFAS in fetal blood is markedly higher than earlier estimates suggested.
Shelley Liu, an associate professor at Mount Sinai and co-author of the study, expressed the significance of these findings, stating, “Babies are exposed to many more PFAS than we previously thought. It’s particularly important to understand because it is a very vulnerable period when fetuses are exposed.”
The Health Dangers of PFAS Exposure
PFAS encompass a large group of approximately 15,000 synthetic compounds, widely utilised for their water-, stain-, and grease-resistant properties. These chemicals have been linked to a plethora of severe health issues, including various cancers, birth defects, weakened immune response, and cardiovascular diseases. Their notorious nickname, “forever chemicals,” derives from their resistance to natural degradation in the environment.

Research has consistently shown that elevated PFAS levels in mothers correlate with adverse outcomes for infants, including increased infant mortality, low birth weight, and long-term obesity. Additionally, fetal exposure to these chemicals has been associated with developmental disorders and chronic health conditions later in life.
Regulatory Shortcomings and Future Implications
Despite the known dangers, efforts to monitor and regulate PFAS in blood, water, and other mediums have been sluggish. The US Environmental Protection Agency (EPA), for instance, typically employs testing methods that only account for roughly 30-40 PFAS compounds. Independent studies, however, have detected thousands of these substances, indicating a significant gap in regulatory oversight.
The Mount Sinai study compared traditional testing methods with the new non-targeted approach, which effectively identified 31 PFAS compounds absent from current EPA standards. Liu pointed out that while the EPA has recently certified a blood test for 53 compounds, this still falls short of capturing the full spectrum of PFAS that could be impacting public health.
The Need for Urgent Action
The implications of these findings are vast. While the study did not directly assess health outcomes, Liu cautioned that elevated PFAS levels in the bloodstream are generally linked to increased health risks. The blood samples analysed were part of the federal government’s Home Study, which tracks PFAS exposure and its effects over time.

David Andrews, acting chief science officer at the Environmental Working Group, underscored the necessity of robust health regulations, stating, “This paper is a stark reminder of the importance of health-protective regulations and how lax oversight can result in babies being born pre-polluted with harmful chemicals such as PFAS.”
Why it Matters
The revelations from this study underscore a critical public health crisis that demands immediate attention. As our understanding of PFAS exposure deepens, it becomes increasingly clear that regulatory frameworks must adapt to protect the most vulnerable among us—our unborn children. The persistence of these chemicals in our environment and bodies poses a severe threat, not just to individual health, but to the well-being of future generations. It is imperative that we push for stricter regulations and comprehensive monitoring to mitigate the risks associated with these toxic substances.