Metal nickel exposure increase the risk of congenital heart defects occurrence in offspring A case-control study in China

Background: Previous studies have investigated heavy metal exposure could increase the occurrence of congenital heart defects (CHDs). However, there are limited data regarding the relationship between exposure to nickel and CHDs occurrence in offspring. The aim of this study was to analyze the association between nickel exposure in mothers and the risk of CHDs in offspring. Materials and methods: To explore the association of nickel exposure and occurrence of CHD, a case-control study with 490 controls and 399 cases with CHDs in China were developed. The concentrations of nickel in hair of pregnant woman and fetal placental tissue were measured and used a logistic regression analysis to explore the relationship between nickel exposure and risk of CHD. Results: The median concentrations of nickel were 0.629ng/mg, P<.05 (adjusted odds ratio [aOR], 1.326; 95% CI, 1.003-1.757) and 0.178ng/mg, P<.05 (aOR, 2.204; 95% CI, 0.783-6.206), in maternal hair and in fetal placental tissue in the CHD group, respectively. Significant differences in the level of nickel in hair were also found in the different CHD subtypes including septal defects (P<.05), conotruncal defects (P<.05), right ventricular outflow tract obstruction (P<.01), and left ventricular outflow tract obstruction (P<.05). Dramatically different nickel concentrations in fetal placenta tissue were found in cases with other heart defects (P<.05). Conclusions: The finding suggested that the occurrence of CHDs may be associated with nickel exposure.