Prenatal exposure to per-and polyfluoroalkyl substances and its association with Developmental Defects of Enamel (DDE) and dental caries in 4 years old children: Findings from Shanghai birth cohort

Abstract

Background: Per- and polyfluoroalkyl substances (PFAS) are persistent environmental contaminants with potential health risks. While the association between PFAS and dental health is under-researched, this study aims to address this gap by investigating prenatal PFAS exposure in relation to Developmental Defects of Enamel (DDE) and dental caries in children.

Methods: This study included 1,136 children from the Shanghai Birth Cohort, with maternal blood samples collected during early pregnancy to measure concentrations of 10 PFAS compounds. Oral health outcomes, assessed when the children were 4 years old, included the prevalence of DDE and dental caries, as well as DDE tooth count and the decayed, missing, and filled teeth (dmft) index. Logistic regression and zero-inflated negative binomial regression were used to examine associations between individual PFAS compounds and oral health outcomes. Restricted Cubic Splines (RCS) were used to explore potential nonlinear associations. Additionally, Bayesian Kernel Machine Regression (BKMR), Weighted Quantile Sum (WQS), and Quantile G-Computation (QGC) were employed to assess the joint effects of PFAS mixtures on the outcomes.

Results: Individual PFAS compounds, particularly perfluorobutane sulfonate (PFBS) and perfluoroheptanoic acid (PFHpA), exhibited heterogeneous associations with DDE prevalence. PFBS was linked to an increased risk of DDE (OR: 1.37; 95%CI: 1.05, 1.80), while PFHpA showed a protective effect (OR: 0.72; 95%CI: 0.54, 0.97). No significant associations were observed between individual PFAS compounds and dental caries outcomes. Additionally, the study found a lack of significant associations between PFAS mixtures and the prevalence of DDE or dental caries, as well as the absence of any marked effects on DDE tooth count or dmft.

Conclusion: Although no overall association was observed between PFAS mixtures and oral health outcomes, certain short-chain PFAS compounds, such as PFBS and PFHpA, demonstrated distinct effects on enamel defects. Further research is warranted to clarify the biological mechanisms underlying these associations and to examine the role of PFAS exposure in other populations.

Keywords: Child; Dental caries; Developmental defects of enamel; Joint effects; Per- and polyfluoroalkyl substances; Prenatal exposure.