Effects Of In Utero Exposure To Polybrominated Diphenyl Ethers On Fetus Development And Placental Insulin-like Growth Factor-1 And Insulin-like Growth Binding Protein-3 Levels In An E-waste Recycling Area

Background: Guiyu as a typical e-waste contaminated area, and its extensive e-waste dismantling process had release large amounts of toxic substances into the environment, including heavy metals, polybrominated diphenyl ethers, polycyclic aromatic hydrocarbons and so on. Many studies had found high levels of polybrominated diphenyl ethers (PBDEs) have been detected in environment, organisms, population and umbilical cord blood in Guiyu. PBDEs is an important environmental pollutants, it is well documented that exposure to PBDEs can cause neural developmental toxicity, endocrine disruption, reproductive toxicity. It can through the placental barrier in pregnant woman and passed to the fetus which may directly or indirectly affect fetal growth and development. However, researches on effects of in utero exposure to PBDEs on fetal growth and development still very limited, so it is very necessary to investigate the adverse health effects of PBDEs on fetal growth and development.Objective:To investigate the association between PBDEs exposure during pregnancy and the expression of Insulin-like Growth Factor-1 (IGF-1) and Insulin-like Growth Factor Binding Protein-3 (IGFBP-3) in fetuses, explore effects of in utero exposure to PBDEs on fetal growth and development. To provide more biological indicators for prenatal exposure to PBDEs effect on fetal growth and development.Methods: We recruited 120 pregnant women (75 from Guiyu, 45 from Chaoan) from December 2009 to June 2010, and carefully collected umbilical cord blood (UCB) and placental tissue during delivery. Questionnaires for personal data were administered. We analyzed PBDE concentrations in UCB by gas chromatography/mass spectrometry. Placental mRNA levels of IGF-1 and IGFBP-3 were determined by real-time PCR.Result:1. Total PBDEs concentrations were significant higher in UCB samples frome Guiyu than control (median 57.55, range 29.57^25th～114.14^75th ng/g lipid vs. 8.23, range 5.74^25th～12.09^75th ng/g lipid, P<0.001). The median individual congener concentrations in UCB samples were significantly increased in Guiyu compare with control (P<0.001). BDE-47,153,209 were the dominant PBDE congeners in UCB in Guiyu.2. Compare with control, infant birth length in Guiyu was significantly decreased (mean 50.36±2.13 vs 51.16±2.03) and Apgar scores was significantly lower (mean 9.81±0.4 vs 9.93±0.25, P<0.05). In addition, BDE-47 and BDE-153 were negatively associated with infant birth length (P <0.05), BDE-28 was negatively correlated with gestational age (P <0.05).3. The expression of IGF-1 mRNA levels in placenta in Guiyu were much high than control (median 0.23 vs 0.19, P <0.05); IGFBP-3 mRNA levels were significantly increased (median 1.91 vs 0.68, P <0.001) in Guiyu compared with the control. The expresson of IGF-1 and IGFBP-3 mRNA levels in placenta were significantly associated with birth weigth in male.4. Increasing concentrations of BDE-183, 209 in UCB were correlated with increase of IGF-1 mRNA levels in female. Total PBDE concentration in UCB was positively associated with the expression of IGFBP-3 mRNA levels in placenta. Multiple regression analysis showed that BDE-209 concentration in UCB was positively correlated with IGF-1 mRNA levels (Rs=0.197), BDE-28 concentration in UCB was positively associated with IGFBP-3 mRNA levels (Rs=0.183). The concentrations of BDE-28 and BDE-209 in UCB were the main reason for the change of IGF-1 and IGFBP-3 levels.Conclusion:The concentration of PBDEs in UCB was still at high level in Guiyu, which BDE-47,153,209 were the main PBDE congeners. Exposure to PBDEs during the pregnancy influences the expression of IGF-1 and IGFBP-3 mRNA level in placenta, which may indirectly affect fetus growth and development. Female neonates may be more sensitively to endocrine disruptor of PBDEs.