title: Manganese concentrations in maternal and umbilical cord blood: related to birth size and environmental factors.
abstract: BACKGROUND
  Manganese (Mn) is an essential element and a potential toxicant for developing organism. Deficiency and excess of it were both deleterious to fetal growth in experimental animals. However, literature on relationship between Mn status and birth outcome in humans is sparse.
  
  
  METHODS
  Mn concentrations were measured in mother whole blood (MWB) and umbilical cord blood (UCB) in 125 pairs of mother-infant; birth size was examined and relationship between them was analysed. Potentially environmental factors influencing Mn loads in maternal and fetal organisms were investigated through epidemiological method.
  
  
  RESULTS
  Mn level in UCB was significantly higher than that in MWB (mean value: 54.98 vs. 78.75 µg/L), and a significant positive correlation was shown between them. There was a quadratic curvilinear (inverted U-shaped curve) relationship between MWB Mn and birth size, and between UCB Mn and birth size. Both univariate analysis and multiple linear regression analysis showed that exposure to harmful occupational factors during gestation remarkably increased maternal and fetal Mn levels. Living close to major transportation routes (<500 m) also increased the MWB Mn levels.
  
  
  CONCLUSIONS
  Our results suggested that lower or higher Mn level in maternal and umbilical blood may induce adverse effect on birth size in humans. In addition, increased levels of Mn in MWB or UCB may be associated with exposure to some environmental hazard factors.
authors.affiliation: 1 Department of Obstetrics and Gynecology, No. 210 Hospital of PLA, Dalian, Liaoning 116021, China.
authors.forename: Huai
authors.initials: H
authors.lastname: Guan
authors.forename: Man
authors.initials: M
authors.lastname: Wang
authors.forename: Xiaowei
authors.initials: X
authors.lastname: Li
authors.forename: Fengyuan
authors.initials: F
authors.lastname: Piao
authors.forename: Qiujuan
authors.initials: Q
authors.lastname: Li
authors.forename: Lei
authors.initials: L
authors.lastname: Xu
authors.forename: Fumihiko
authors.initials: F
authors.lastname: Kitamura
authors.forename: Kazuhito
authors.initials: K
authors.lastname: Yokoyama
mesh_terms: D000328:Adult; D001724:Birth Weight; D001827:Body Height; D002681:China / Q000453:epidemiology; D003430:Cross-Sectional Studies; D004781:Environmental Exposure / Q000009:adverse effects*; D005260:Female; D005312:Fetal Blood / Q000737:chemistry*; D006257:Head / Q000033:anatomy & histology; D006801:Humans; D007231:Infant, Newborn; D008345:Manganese / Q000009:adverse effects / Q000032:analysis*; D011247:Pregnancy / Q000097:blood*; D013909:Thorax / Q000033:anatomy & histology
chemical_list: D008345:Manganese