TUESDAY, Feb. 24, 2026 (HealthDay News) -- Infants are exposed to a wider range of per- and polyfluoroalkyl substances (PFAS) before birth than previously thought, according to a study published online Feb. 18 in Environmental Science & Technology.Shelley H. Liu, Ph.D., from the Icahn School of Medicine at Mount Sinai in New York City, and colleagues examined PFAS exposure in archived umbilical cord blood samples collected between 2003 and 2006 from participants in the Health Outcomes and Measures of the Environment (HOME) Study. Participants included those who had targeted PFAS analysis data collected (216 mother-infant dyads) and those who had nontargeted PFAS data collected (120 mother-infant dyads). The researchers found that a nontargeted chemical analysis method detected many more PFAS chemicals in umbilical cord blood than traditional testing methods, including newer and understudied compounds. The nontargeted approach identified 42 confirmed or putatively identified PFAS chemicals in cord blood, many of which are not commonly screened for in traditional testing methods and for which health effects are unknown, including perfluorinated chemicals, polyfluorinated chemicals, and fluorotelomers. A targeted analysis identified four PFAS."Our study helps show that prenatal PFAS exposure is more complex and widespread than earlier studies suggested," Liu said in a statement. "Understanding the full picture is essential if we want to protect child health and reduce preventable environmental risks."Abstract/Full Text (subscription or payment may be required).Sign up for our weekly HealthDay newsletter