New peer-reviewed research shows fetuses likely have much higher levels of Pfas “forever chemicals” in their blood than previously thought.

Testing of umbilical cord blood typically looks for a small number of common Pfas compounds, like Pfoa and Pfos. However, thousands of Pfas exist, and a new Mount Sinai study tested 120 umbilical blood cord samples that were previously found to contain up to four compounds.

The expanded “non-targeted analysis” identified 42 Pfas compounds across the 120 samples, and the total level of Pfas in the blood was much higher than previously found.

The findings suggest “babies are exposed to many more Pfas than we previously thought”, said Shelley Liu, a study co-author and associate professor at the Icahn School of Medicine at Mount Sinai.

“It’s particularly important to understand because it is a very vulnerable period when fetuses are exposed,” Liu added.

Pfas are a class of about 15,000 compounds most frequently used to make products water-, stain- and grease-resistant. The chemicals have been linked to cancer, birth defects, decreased immunity, high cholesterol, kidney disease and a range of other serious health problems. They are dubbed “forever chemicals” because they do not naturally break down in the environment.