Figure 1

Bivariate analysis of placental global DNA methylation in association with prenatal exposure to fine particulate air pollution (PM _2.5 ). PM_2.5 exposures (μg/m³) are presented with spearman correlation coefficients for the whole pregnancy (A) and first trimester (B). In panel C, the association between average PM_2.5 concentrations and placental global DNA methylation is given. The effect of the average concentrations over 91 days periods was estimated using restricted cubic splines with 5 knots located at the 5^th, 25^th, 50^th, 75^th and 95^th percentiles.