Fluorotelomer ethoxylates cause developmental toxicity in mice

Poly- and perfluoroalkyl substances are a ubiquitous class of compounds which are considered persistent organic pollutants. Many of these compounds are unregulated and understudied but are still widely used. One group of these compounds are fluorotelomer ethoxylates, which recently emerged as compounds of interest following their detection in the environment. To determine the health impacts of these persistent compounds, healthy pregnant CD-1 mice were exposed to 0 ng L⁻¹ (n = 8), 5 ng L⁻¹ (n = 8), or 100 ng L⁻¹ (n = 7) fluorotelomer ethoxylates in drinking water throughout gestation. At gestational day 17.5 (term is 18.5 days), high-frequency ultrasound was performed to investigate the placental and fetal hemodynamic responses following exposure. Maternal exposure to fluorotelomer ethoxylates showed evidence of placental insufficiency, with a significant increase in placental weights (p < 0.05), a decrease in the umbilical artery blood flow (p < 0.01) and vasodilation of the cerebral circulation (p < 0.01), consistent with brain sparing to preserve oxygen delivery to the brain. These results demonstrate that fluorotelomer ethoxylates cause developmental toxicity and motivate further work to evaluate the risk to human pregnancies and other vulnerable populations.