ABSTRACT
Electronic waste recycling produces Polycyclic Aromatic Hydrocarbons (PAHs) and Polybrominated Diphenyl Ethers (PBDEs) which may affect fetal growth and development by altering the insulin-like-growth factor (IGF) system. Questionnaires were administered to pregnant women (Guiyu, an e-waste site, n = 101; control, n = 53), and umbilical cord blood (UCB) and placentas were collected upon delivery. PBDEs and PAHs in UCB and placental IGF-1 and IGFBP-3 mRNA levels were analyzed using GC-MS and real-time PCR, respectively. Infant birth length and Apgar scores were lower in Guiyu. All PAHs (except Fl, Chr, IP, BbF and BP), total 16-PAHs, total/individual PBDEs, placental IGF-1 (median 0.23 vs 0.19; P < 0.05) and IGFBP-3 (median 1.91 vs 0.68; P < 0.001) levels were significantly higher in Guiyu. Spearman correlation showed that BDE-154, BDE-209 and ∑5ring-PAHs positively correlate with IGF-1 while PBDEs, 4 rings and total PAHs correlate with IGFBP-3 expression. Increased placental IGF-1 level might indirectly affect fetal growth and development.
Subject(s)
Electronic Waste , Environmental Pollutants/blood , Halogenated Diphenyl Ethers/blood , Insulin-Like Growth Factor Binding Protein 3/metabolism , Insulin-Like Growth Factor I/metabolism , Maternal Exposure , Polycyclic Aromatic Hydrocarbons/blood , Adult , Environmental Monitoring/methods , Environmental Pollutants/toxicity , Female , Fetal Blood/metabolism , Halogenated Diphenyl Ethers/toxicity , Humans , Male , Placenta/metabolism , Polycyclic Aromatic Hydrocarbons/toxicity , Pregnancy , RNA, Messenger/metabolismABSTRACT
Toxic heavy metals are released to the environment constantly from unregulated electronic waste (e-waste) recycling in Guiyu, China, and thus may contribute to the elevation of lead and other heavy metals levels in placenta. We aimed to investigate concentrations of heavy metals, including lead (Pb), cadmium (Cd), chromium (Cr), and nickel (Ni) in placenta from Guiyu and compared them with those from a control area where no e-waste processing occurs. Two hundred and twenty human placentas were collected from Guiyu (n=101) and the control area (n=119). The placenta concentrations of Pb, Cd, Cr, and Ni (PCPb, PCCd, PCCr, and PCNi) were determined by graphite furnace atomic absorption spectrometry (GFAAS). Risk factors of high exposure and correlation with adverse pregnancy outcomes were analyzed using Spearman correlation analyses. PCPb from Guiyu ranged from 6.51 to 3465.16ng/g with a median of 301.43ng/g, whereas PCPb from the control area ranged from 4.53 to 3176.12ng/g with a median of 165.82ng/g (P=0.010). We also observed that in Guiyu, 41.6% of women (42/101) had PCPb>500ng/gwt (wet weight), compared with 24.4% of women (29/119) in the control area (P=0.006). No significant differences of PCCd and PCCr were found between the two groups. In contrast, PCNi was higher in samples from the control area (median 14.30, range 1.76-593.70ng/g) than in Guiyu samples (median 7.64, range 1.19-1108.99ng/g) (P=0.000), and a negative correlation between PCNi and gestational age was found in this study (P=0.017). Spearman correlation analyses showed that there was correlation between PCPb and residence in e-waste recycling area. Environmental pollution, resulted from unregulated e-waste recycling activities, may contribute to elevated PCPb in neonates born in Guiyu and threaten their health.
