PM2.5 Components and Fetal Chromosomal Abnormalities: Identifying Critical Exposure Windows

PM_2.5 is genotoxic and linked to fetal chromosomal abnormalities. This study aims to explore the association between PM_2.5 components (SO₄^2–, NO₃^–, NH₄⁺, OM, BC) and fetal chromosomal abnormalities. We conducted a cross-sectional study spanning four consecutive years (2019–2022), using samples collected from General Hospital of Tianjin Medical University. A total of 901 samples were analyzed, including 95 cases. Logistic regression and stratified analyses were employed to examine the associations between specific PM_2.5 components and fetal chromosomal abnormalities across 14 distinct exposure windows. The goal was to identify the critical periods of exposure that may contribute to fetal chromosomal abnormalities and to screen vulnerable subgroups. Our findings revealed significant associations between PM_2.5 components (NO₃^–, NH₄⁺, OM) and fetal chromosomal abnormalities during four key exposure windows: 8, 12, and 16 weeks prior to the last menstrual period, as well as during spermatogenesis. Younger pregnant women (<35 years) and those with higher or lower BMI were found to be more susceptible to PM_2.5 components, increasing the risk to their fetus. These findings suggest that minimizing maternal exposure to PM_2.5 during these critical time windows and maintaining a normal BMI may effectively reduce the incidence of fetal chromosomal abnormalities.