Fig. 6
From: PM2.5 constituent exposures and maternal circulatory homocysteine in early pregnancy
Thirteen − week (3 − month) cumulative associations of an IQR increase in PM2.5 and constituent exposures with percentage changes in serum Hcy in all participants (n = 324), EPL group (n = 162), and NEP group (n = 162). Note: The independent variables simultaneously included three cross–basis functions generated by lag 1–13 weeks before serum collection and weekly exposure to pollutant (concentration of PM2.5 or each constituent in [A], replaced by residual of each constituent in [B]), temperature, and relative humidity, respectively, Ln5-MeTHF, all demographic characteristics presented in Table 1, and group (EPL or NEP). The IQRs of concentration of PM2.5, BC, OM, NO3–, NH4+, and SO42– in the analyses were 29, 1.1, 5.8, 6.7, 3.6, and 2.5 µg/m3, respectively. The IQRs of residual of BC, OM, NO3–, NH4+, and SO42– in the analyses were 0.2, 0.9, 1.5, 0.9, and 1.1, respectively