In utero exposure to dioxins and polychlorinated biphenyls and its relations to thyroid function and growth hormone in newborns.
The aim of this study is to examine the association between transplacental exposure to dioxins/polychlorinated biphenyls (PCBs) and thyroid and growth hormones in newborns. We recruited 118 pregnant women, between 25 and 34 years of age, at the obstetric clinic. Personal data collected included reproductive and medical histories and physical factors. Clinicians gathered placental and umbilical cord serum upon delivery and carefully scored the 118 newborns, making both structural and functional assessments. We analyzed placentas for 17 polychlorinated dibenzo-p-dioxins and dibenzofurans and 12 dioxin-like PCB congeners with the World Health Organization-defined toxic equivalent factors, and six indicator PCBs by high-resolution gas chromatography and high-resolution mass spectrometry. We analyzed thyroid and growth hormones from cord serum using radioimmunoassay. Insulin-like growth factor (IGF)-1, IGF-binding globulin-3, and thyroxine x thyroid-stimulating hormone (T4 x TSH) were significantly associated with increased placental weight and Quetelet index (in kilograms per square meter; correlation coefficient r = 0.2-0.3; p < 0.05). Multivariate analyses showed independently and significantly decreased free T4 (FT4) x TSH with increasing non-ortho PCBs (r = -0.2; p < 0.05). We suggest that significant FT4 feedback alterations to the hypothalamus result from in utero exposure to non-ortho PCBs. Considering the vast existence of bioaccumulated dioxins and PCBs and the resultant body burden in modern society, we suggest routine screening of both thyroid hormone levels and thyroid function in newborns.
Wang
Shu-Li
SL
Division of Environmental Health and Occupational Medicine, National Health Research Institutes, and Graduate Institute of Occupational Safety and Health, Kaohsiung Medical University, Kaohsiung, Taiwan. slwang@nhri.org.tw
Su
Pen-Hua
PH
Jong
Shiang-Bin
SB
Guo
Yueliang L
YL
Chou
Wei-Ling
WL
Päpke
Olaf
O
D000328:Adult; D001572:Benzofurans / Q000032:analysis / Q000633:toxicity; D000072338:Dibenzofurans, Polychlorinated; D004784:Environmental Monitoring; D004785:Environmental Pollutants / Q000032:analysis / Q000633:toxicity*; D005260:Female; D005312:Fetal Blood / Q000737:chemistry; D006801:Humans; D007231:Infant, Newborn; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000378:metabolism; D007334:Insulin-Like Growth Factor I / Q000378:metabolism; D008297:Male; D018811:Maternal Exposure; D010920:Placenta / Q000737:chemistry; D011078:Polychlorinated Biphenyls / Q000032:analysis / Q000633:toxicity*; D000072317:Polychlorinated Dibenzodioxins / Q000031:analogs & derivatives / Q000032:analysis / Q000633:toxicity; D011247:Pregnancy; D013624:Taiwan; D013972:Thyrotropin / Q000378:metabolism; D013974:Thyroxine / Q000378:metabolism*
D001572:Benzofurans; D000072338:Dibenzofurans, Polychlorinated; D004785:Environmental Pollutants; D018972:Insulin-Like Growth Factor Binding Protein 3; D000072317:Polychlorinated Dibenzodioxins; D007334:Insulin-Like Growth Factor I; D013972:Thyrotropin; D011078:Polychlorinated Biphenyls; D013974:Thyroxine