Parental Occupational Exposures to Endocrine Disruptors and the Risk of Simple Isolated Congenital Heart Defects

Abstract

This study aims to explore the associations between parental occupational exposures to endocrine disruptors (EDs) and simple isolated congenital heart defects (CHDs). A case-control study with standardized data collection involving 761 children with isolated CHDs and 609 children without any congenital malformations was conducted in Sichuan Province of China from March in 2012 to August in 2013. An adjusted job exposure matrix was used for occupational EDs exposure assessment. Logistic regression analysis was performed to assess the associations between parental occupational EDs exposures and CHDs. Maternal age at births, maternal education level, gravity, parity, induced abortion, folic acid use, medication use, drinking capacity and area of residence periconceptionally were selected as confounding factors for mothers. For fathers, we selected the following confounding factors: paternal education level, smoking, drinking frequencies and drinking capacity periconceptionally. Maternal occupational exposures to phthalates are associated with perimembranous ventricular septal defect (PmVSD) (P = 0.001, adjusted OR 3.7, 95 % CI 1.7-8.0), patent ductus arteriosus (PDA) (P = 0.002, adjusted OR 3.8, 95 % CI 1.6-8.9), secundum atrial septal defect (s-ASD) (P = 0.008, adjusted OR 3.5, 95 % CI 1.4-8.7) and pulmonary valve stenosis (PS) (P = 0.035, adjusted OR 4.2, 95 % CI 1.1-16.0), to alkylphenolic compounds and PmVSD (P = 0.003, adjusted OR 2.2, 95 % CI 1.3-3.6), PDA (P = 0.005, adjusted OR 2.0, 95 % CI 1.1-3.5) and PS (P = 0.004, adjusted OR 3.8, 95 % CI 1.5-9.4), to heavy metals with PmVSD (P = 0.003, adjusted OR 7.3, 95 % CI 2.0-27.6) and s-ASD (P = 0.034, adjusted OR 6.5, 95 % CI 1.1-36.7). Paternal occupational exposures to phthalates are associated with PmVSD (P = 0.035, adjusted OR 1.6, 95 % CI 1.0-2.4) and PS (P = 0.026, adjusted OR 2.4, 95 % CI 1.1-5.2), to alkylphenolic compounds (P = 0.027, adjusted OR 1.5, 95 % CI 1.0-2.2) with PmVSD. In conclusion, parental occupational exposures to some specific EDs, in particular phthalates and alkylphenolic compounds, are associated with an increased risk of some CHD phenotypes. However, the findings need to be considered more circumspectly regarding a crude measure of exposure probabilities and small numbers.