Endocrine Disruptors and Earlier Pubertal Timing in Girls: Mechanisms, Evidence, and Controversies

Objective: To examine evidence on endocrine disruptors and earlier pubertal timing in girls, considering mechanisms, exposure windows, and controversies. Sources: Narrative synthesis of 24 publications, including human observational studies, reviews, and one preclinical study. Six additional articles supported the clinical and mechanistic background. Summary of the findings: Associations varied by compound, exposure window, and outcome. Some phthalates and parabens were associated with earlier milestones, whereas findings for bisphenol A (BPA) and per- and polyfluoroalkyl substances (PFAS) were mixed. Experimental receptor activation suggests biological plausibility but does not establish clinical effects. Single exposure measurements, confounding, reverse causality, and overlapping evidence limit interpretation. Conclusions: Current evidence does not establish that endocrine disruptors cause earlier puberty in girls. Earlier milestones do not necessarily indicate central precocious puberty. Prospective studies with repeated exposure measurements and standardized outcomes are needed.