Figure 3.

Comparison between the associations of urinary arsenic and water arsenic with genome-wide methylation in the Health Effects of Arsenic Longitudinal Study (HEALS). The direction of association and $-{\log }_{10}\left(p\right)$ for each CpG–arsenic association are plotted for urinary (x-axis) and water (y-axis) (both ${\log }_2\text{\hspace{0.17em} transformed}$). Solid lines and dashed lines designate $-{\log }_{10}\left(p=1\right)$ and $-{\log }_{10}\left(p=0.05\right)$, respectively. CpGs highlighted in blue diamonds denote ${\log }_2\text{-transformed}$ urinary arsenic–associated sites [$\text{false discovery rate \hspace{0.17em}}\left(\text{FDR}\right)<0.05$]. Pearson’s correlation between all urinary and water arsenic CpG associations was 0.67 ($p<{10}^{-16}$).