Nicotine and metabolites in paired umbilical cord tissue and meconium specimens.

Umbilical cord tissue was studied as a means of detecting prenatal exposure to nicotine. This was accomplished by comparing the presence and concentration of nicotine as well as nicotine metabolites in both umbilical cord tissue and paired meconium samples with maternal smoking histories obtained by self-report. Nicotine and metabolites (cotinine, 3-hydroxycotinine, nornicotine, and anabasine) were detected and quantitated using liquid chromatography-tandem mass spectroscopy. Between June and September 2009, 19 women with a tobacco exposure history (either first- or second-hand tobacco smoke exposure during pregnancy) were consented for the study. A questionnaire was completed to document nicotine exposure during each trimester of pregnancy. All infants were delivered at term (38 weeks or greater) and paired umbilical cord tissue (10-cm segment or greater) and meconium were obtained. Nicotine and 3-hydroxycotinine were most prominent in meconium, whereas cotinine and 3-hydroxycotinine were most prominent in the umbilical cord. Concentrations of all three analytes were generally higher in meconium. Nornicotine was detected only in meconium, at very low concentrations, and anabasine was not detected in either specimen. All analyte concentrations were lowest when the mother stated she quit smoking early in pregnancy or had only second-hand exposure, and detection was poor if exposure was limited to the first or second trimesters. Although different nicotine and metabolite patterns exist in meconium versus umbilical cord tissue, this work indicates that either specimen can be used to detect third-trimester fetal nicotine exposure.