Fetal Exposure to Persistent and Semi-Persistent Organic Pollutants in the Environment: Accumulation Mechanisms and Health Consequences

Abstract

Persistent and semi-persistent organic pollutants (POPs and semi-POPs) represent an important class of environmental contaminants because of their widespread distribution, persistence, bioaccumulation potential, and adverse effects on human health. Pregnancy is a particularly vulnerable period, as many of these compounds can cross the placental barrier and expose the developing fetus during critical stages of growth and organogenesis. This review summarizes current evidence regarding the environmental sources, maternal exposure pathways, placental transport mechanisms, fetal accumulation, and health consequences associated with prenatal exposure to persistent and semi-persistent organic pollutants. Published biomonitoring studies consistently detect per- and polyfluoroalkyl substances (PFAS), polychlorinated biphenyls (PCBs), organochlorine pesticides, bisphenol A (BPA), and phthalates in maternal serum, placenta, cord blood, and other fetal-related biological matrices, confirming widespread fetal exposure. The efficiency of placental transfer depends on physicochemical properties, including lipophilicity, molecular size, ionization state, protein binding, and metabolic stability. Experimental and epidemiological evidence indicates that these pollutants induce oxidative stress, endocrine disruption, mitochondrial dysfunction, inflammation, and epigenetic modifications, thereby impairing placental function and fetal development. Prenatal exposure has been associated with reduced birth weight, preterm birth, neurodevelopmental impairment, immune dysfunction, and adverse metabolic outcomes during childhood. Advances in analytical techniques, particularly high-performance liquid chromatography (HPLC) and mass spectrometry-based methods, have substantially improved the detection and quantification of these contaminants in biological samples, enabling more accurate exposure assessment. Future research should prioritize standardized biomonitoring protocols, repeated exposure measurements throughout pregnancy, mixture-based exposure assessment, and long-term prospective birth cohorts to improve risk evaluation and strengthen evidence for protecting maternal and fetal health.