title: Determinants of plasma PCB, brominated flame retardants, and organochlorine pesticides in pregnant women and 3 year old children in The Norwegian Mother and Child Cohort Study.
abstract: BACKGROUND
  Exposure to persistent organic pollutants (POPs) during prenatal and postnatal life has been extensively studied in relation to adverse health effects in children.
  
  
  OBJECTIVE
  The aim was to identify determinants of the concentrations of polychlorinated biphenyls (PCBs), brominated flame retardants (polybrominated diphenyl ethers, PBDEs; polybrominated biphenyl, PBB), and organochlorine pesticides (OCPs) in blood samples from pregnant women and children in The Norwegian Mother and Child Cohort Study (MoBa).
  
  
  METHODS
  Blood samples were collected from two independent subsamples within MoBa; a group of women (n=96) enrolled in mid-pregnancy during the years 2002-2008 and a group of 3 year old children (n=99) participating during 2010-2011. PCB congeners (74, 99, 138, 153, 180, 170, 194, 209, 105, 114, 118, 156, 157, 167, and 189), brominated flame retardants (PBDE-28, 47, 99, 100, 153, 154, and PBB-153), as well as the OCPs hexachlorobenzene (HCB), oxychlordane, 4,4'dichlorodiphenyltrichloroethane (DDT), and 4,4'dichlorodiphenyldichloroethylene (DDE) were measured in both pregnant women and children.
  
  
  RESULTS
  Age, low parity, and low pre-pregnant BMI were the most important determinants of increased plasma concentrations of POPs in pregnant women. In 3 year old children, prolonged breastfeeding duration was a major determinant of increased POP concentrations. Estimated dietary exposure to PCBs during pregnancy was positively associated with plasma concentrations in 3 year old children, but not in pregnant women. Plasma concentrations were approximately 40% higher in children compared to pregnant women.
  
  
  CONCLUSIONS
  Several factors associated with exposure and toxicokinetics, i.e. accumulation, excretion and transfer via breastmilk of POPs were the main predictors of POP levels in pregnant women and children. Diet, which is the main exposure source for these compounds in the general population, was found to predict PCB levels only among children. For the PBDEs, for which non-dietary sources are more important, toxicokinetic factors appeared to have less predictive impact.
authors.affiliation: Norwegian Institute of Public Health, P.O. Box 4404 Nydalen, NO-0403 Oslo, Norway. Electronic address: ida.henriette.caspersen@fhi.no.
authors.forename: Ida Henriette
authors.initials: IH
authors.lastname: Caspersen
authors.affiliation: Norwegian Institute of Public Health, P.O. Box 4404 Nydalen, NO-0403 Oslo, Norway; Bjørknes College, Lovisenberggata 13, NO-0456 Oslo, Norway.
authors.forename: Helen Engelstad
authors.initials: HE
authors.lastname: Kvalem
authors.affiliation: Norwegian Institute of Public Health, P.O. Box 4404 Nydalen, NO-0403 Oslo, Norway.
authors.forename: Margaretha
authors.initials: M
authors.lastname: Haugen
authors.affiliation: Norwegian Institute of Public Health, P.O. Box 4404 Nydalen, NO-0403 Oslo, Norway.
authors.forename: Anne Lise
authors.initials: AL
authors.lastname: Brantsæter
authors.affiliation: Norwegian Institute of Public Health, P.O. Box 4404 Nydalen, NO-0403 Oslo, Norway.
authors.forename: Helle Margrete
authors.initials: HM
authors.lastname: Meltzer
authors.affiliation: Norwegian Institute of Public Health, P.O. Box 4404 Nydalen, NO-0403 Oslo, Norway.
authors.forename: Jan
authors.initials: J
authors.lastname: Alexander
authors.affiliation: Norwegian Institute of Public Health, P.O. Box 4404 Nydalen, NO-0403 Oslo, Norway.
authors.forename: Cathrine
authors.initials: C
authors.lastname: Thomsen
authors.affiliation: Norwegian Institute of Public Health, P.O. Box 4404 Nydalen, NO-0403 Oslo, Norway.
authors.forename: May
authors.initials: M
authors.lastname: Frøshaug
authors.affiliation: Norwegian Institute of Public Health, P.O. Box 4404 Nydalen, NO-0403 Oslo, Norway.
authors.forename: Nanna Margrethe Bruun
authors.initials: NM
authors.lastname: Bremnes
authors.affiliation: Norwegian Institute of Public Health, P.O. Box 4404 Nydalen, NO-0403 Oslo, Norway.
authors.forename: Sharon Lynn
authors.initials: SL
authors.lastname: Broadwell
authors.affiliation: Norwegian Institute of Public Health, P.O. Box 4404 Nydalen, NO-0403 Oslo, Norway.
authors.forename: Berit
authors.initials: B
authors.lastname: Granum
authors.affiliation: Centre for Research in Environmental Epidemiology (CREAL), Doctor Aiguader 88, Barcelona, Spain; IMIM (Hospital del Mar Medical Research Institute), Barcelona, Spain; CIBER Epidemiologia y Salud Pública (CIBERESP), Madrid, Spain.
authors.forename: Manolis
authors.initials: M
authors.lastname: Kogevinas
authors.affiliation: Norwegian Institute of Public Health, P.O. Box 4404 Nydalen, NO-0403 Oslo, Norway.
authors.forename: Helle Katrine
authors.initials: HK
authors.lastname: Knutsen
mesh_terms: D002675:Child, Preschool; D015331:Cohort Studies; D003710:Demography; D004032:Diet; D004781:Environmental Exposure; D004784:Environmental Monitoring; D004785:Environmental Pollutants / Q000097:blood*; D005260:Female; D005411:Flame Retardants / Q000378:metabolism*; D006801:Humans; D006842:Hydrocarbons, Brominated / Q000097:blood*; D006843:Hydrocarbons, Chlorinated / Q000097:blood*; D008019:Life Style; D009664:Norway; D010575:Pesticides / Q000097:blood*; D011075:Polybrominated Biphenyls / Q000097:blood; D011078:Polychlorinated Biphenyls / Q000097:blood; D011247:Pregnancy
chemical_list: D004785:Environmental Pollutants; D005411:Flame Retardants; D006842:Hydrocarbons, Brominated; D006843:Hydrocarbons, Chlorinated; D010575:Pesticides; D011075:Polybrominated Biphenyls; D011078:Polychlorinated Biphenyls
keywords: MoBa; OCP; PBDE; PCB; The Norwegian Mother and Child Cohort Study