Per- and polyfluoroalkyl substances (PFAS) in powdered infant formula: potential exposures and health risks

Per- and polyfluoroalkyl substances (PFAS) are a class of human-made persistent, bioaccumulative, and toxic compounds. People can be exposed to PFAS through many different pathways, including food, drinking water, and PFAS-containing consumer products. Infants are recognized as particularly susceptible to the harmful effects of PFAS while also being among the most highly exposed populations. Exposure to PFAS begins in utero via placental transfer and can continue after birth from environmental exposures and breastfeeding. PFAS-contaminated water, if used to mix infant formula, is an important potential exposure route for formula-fed infants because they consume more fluid on a per-body-weight basis than older individuals. However, data about potential PFAS exposures from powdered infant formula itself are lacking. To address this data gap, we analyzed 17 powdered infant formulas for 10 different PFAS. Only one type of PFAS, perfluorooctanesulfonic acid (PFOS), was detected in a single dairy-based formula at a reconstituted concentration of 8.9 ng/L. Using our recently updated toxicokinetic model, we estimated serum PFOS concentration curves over the first year of life for various exposure scenarios, including different fluid intake rates, formula reconstituted with uncontaminated and contaminated water, and with and without placental transfer. Our analytical results indicate the single PFOS detection in powdered infant formula is not a major source of PFOS relative to other sources, and our risk assessment comparing various formula-fed infant scenarios to the Minnesota Department of Health’s 2024 PFOS reference serum concentration (2.6 ng/mL) concludes that PFAS from powdered formula likely does not pose a significant risk to infants.