Correlation of Nickel and Arsenic Levels in Mid-Pregnancy Women with Neonatal Umbilical Cord Blood Biomarkers

Objective To investigate the correlation of nickel (Ni) and arsenic (As) levels in pregnant women in mid-pregnancy with neonatal umbilical cord blood biomarkers.

Methods Baseline data were collected from 57 pairs of pregnant women and neonates in place A and 79 pairs in place B; venous blood samples were collected from the pregnant women in mid-pregnancy and umbilical cord blood samples were collected from neonates at peripartum. Inductively coupled plasma mass spectrometry was used to measure the levels of Ni and As in pregnant women; The ELISA was used to measure plasma interleukin-6 (IL-6) in umbilical cord blood; an automatic biochemical analyzer was used to measure the levels of C-reactive protein (CRP), total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) in umbilical cord blood. The Spearman rank correlation test and multiple linear regression analysis were used to investigate the correlation of Ni and As levels in pregnant women with biomarker levels in neonates.

Results The pregnant women in mid-pregnancy in place A had significantly higher levels of Ni and As in venous blood than those in place B (Z=-5.98 and -4.17, P < 0.05). The neonates in place A had significantly higher levels of CRP and TG than those in place B (Z=-4.75 and -2.28, P < 0.05), while there were no significant differences in the levels of IL-6, TC, HDL-C and LDL-C among them (P >0.05). The Spearman rank correlation test showed that Ni and As levels in the pregnant women in mid-pregnancy were positively correlated with CRP in neonates (r_s=0.238 and 0.183, P < 0.05), and the level of Ni was positively correlated with TG in neonates (r_s=0.175, P < 0.05). The multiple linear regression analysis showed that neonatal CRP level was positively correlated with Ni level in the venous blood of pregnant women (β=1.458, 95%CI: 1.144-1.859), and neonatal TG level was positively correlated with As level in the venous blood of pregnant women (β=1.140, 95%CI: 1.090-1.191).

Conclusion Exposure to Ni and As in mid-pregnancy is associated with the increases in neonatal umbilical cord blood biomarkers, and thus pregnant women should avoid or reduce the exposure to Ni and As during pregnancy.