Characterization of placental transfer of polychlorinated dibenzo-p-dioxins, dibenzofurans and polychlorinated biphenyls in normal pregnancy
Article first published online: 4 JUN 2012
© 2012 The Authors. Journal of Obstetrics and Gynaecology Research © 2012 Japan Society of Obstetrics and Gynecology
Journal of Obstetrics and Gynaecology Research
Volume 39, Issue 1, pages 83–90, January 2013
How to Cite
Tsukimori, K., Morokuma, S., Hori, T., Takahashi, K., Hirata, T., Otera, Y., Fukushima, K., Kawamoto, T. and Wake, N. (2013), Characterization of placental transfer of polychlorinated dibenzo-p-dioxins, dibenzofurans and polychlorinated biphenyls in normal pregnancy. Journal of Obstetrics and Gynaecology Research, 39: 83–90. doi: 10.1111/j.1447-0756.2012.01906.x
- Issue published online: 7 JAN 2013
- Article first published online: 4 JUN 2012
- Received: October 31 2011.; Accepted: March 3 2012.
- placental physiology;
- placental transfer;
- polychlorinated biphenyl
Aim: Prenatal exposure to dioxins may result in many adverse health effects. However, the mechanisms by which dioxins are transferred from mother to fetus through the placenta are not well understood. The aim of this study was to investigate the differences in dioxin concentrations between maternal blood, the placenta, and cord blood in normal pregnant women, and to identify which individual congeners of these compounds are transferred from mother to fetus through the placenta.
Material and Methods: Samples were collected from 19 pregnant Japanese women. Specific congeners of seven polychlorinated dibenzo-p-dioxins (PCDDs), 10 polychlorinated dibenzofurans (PCDFs), and four non-ortho polychlorinated biphenyls (PCBs) were analyzed.
Results: The TEQ concentrations of PCDDs, PCDFs, and non-ortho PCBs were 8.03, 3.39, and 3.95 pg TEQ/g lipid, respectively, in the maternal blood; 8.78, 3.61, and 0.87 pg TEQ/g lipid in the placenta; and 4.33, 1.25, 1.08 pg TEQ/g lipid in the cord blood. Among specific congeners, 1,2,3,7,8-PentaCDD and 2,3,4,7,8-PentaCDF exhibited a placenta to maternal blood ratio greater than 1.0, while OctaCDD exhibited the greatest cord blood to placenta ratio. The cord blood to maternal blood ratio of total PCDDs was significantly higher than that of total PCDFs and total non-ortho PCBs.
Conclusion: The dioxin concentration in cord blood was approximately half of the amount in maternal blood, despite congeners showing a high toxic equivalency factor accumulating in the placenta. PCDDs were transferred more readily than PCDFs and non-ortho PCBs from maternal blood to the fetus through the placenta.