Necessity to Measure PCBs and Organochlorine Pesticide Concentrations in Human Umbilical Cords for Fetal Exposure Assessment Hideki Fukata,1,2 Mariko Omori,1,2,3,4 Hisao Osada,2,5 Emiko Todaka,2,4,6 and Chisato Mori2,4 1Department of Environmental Medical Science, 2Environmental Health Science Project for Future Generations, 3Department of Reproductive Medicine, and 4Department of Bioenvironmental Medicine, Graduate School of Medicine, Chiba University, Chiba, Japan; 5Department of Obstetrics and Gynecology, Chiba University Hospital, Chiba, Japan; 6Center for Environment, Health and Field Sciences, Chiba University, Kashiwa, Japan Abstract Three types of tissue samples--umbilical cord (UC) , umbilical cord serum (CS) , and maternal serum (MS) --have often been used to assess fetal exposure to chemicals. In order to know the relationship of contamination between mothers and fetuses, we measured persistent chemicals in comparable sets of the three tissue samples. Also, we analyzed the association between the chemicals in maternal and fetal tissues to know which tissue is the best sample for fetal exposure assessment. On a wet basis, the chemical concentrations were of the order MS > CS > UC, except for some chemicals such as cis-chlordane and endosulfan. On a lipid basis, the concentrations in UC were nearly equal or often higher than in MS, but the concentrations in CS were usually lower than in others. Hexachlorocyclohexanes and penta-, hexa-, and heptachlorinated biphenyls showed an association between the concentrations in UC versus MS, and UC versus CS. These chemicals also showed high correlation coefficients between the chemical concentrations in UC of first babies and maternal age. These chemicals were closely related to each other when grouped on the basis of their concentrations using cluster analysis. In conclusion, we insist that UC is the best sample to assess fetal contamination status of persistent chemicals. There is a possibility that the assessment based on the contamination levels in CS result in an underestimation. Key words: cord blood, maternal blood, organochlorine pesticides, polychlorinated biphenyls (PCBs) , umbilical cord. Environ Health Perspect 113:297-303 (2005) . doi:10.1289/ehp.7330 available via http://dx.doi.org/ [Online 14 December 2004] Address correspondence to C. Mori, Department of Bioenvironmental Medicine, Graduate School of Medicine, Chiba University, Chiba 260-8670 Japan. Telephone: 81-43-226-2017. Fax: 81-43-226-2018. E-mail: cmori@faculty.chiba-u.jp This work was supported by grants from the Ministry of the Environment (Government of Japan) and the Ministry of Education, Culture, Sports, Science and Technology (Government of Japan) . The authors declare they have no competing financial interests. Received 16 June 2004 ; accepted 14 December 2004. The full version of this article is available for free in HTML or PDF formats. |