title: Colostrum iodine and perchlorate concentrations in Boston-area women: a cross-sectional study.
abstract: OBJECTIVE
  To measure levels of colostrum iodine, which has not been previously measured, and perchlorate and cotinine (a surrogate for thiocyanate derived from cigarette smoke) in women up to 60 h postpartum. Perchlorate and thiocyanate are environmental inhibitors of iodide transport into the thyroid and lactating breast.
  
  
  METHODS
  Cross-sectional.
  
  
  METHODS
  Ninety seven postpartum women in Boston, Massachusetts, USA.
  
  
  METHODS
  Colostrum iodine and perchlorate, and spot urine iodine, perchlorate, cotinine and creatinine concentrations were measured.
  
  
  RESULTS
  Sufficient colostrum was obtained to measure iodine in 61 samples and perchlorate in 46 samples. Median colostrum iodine content was 51.4 micromol/l (range 21.3-304.2 microg/l). Perchlorate was detectable in 43 of 46 colostrum samples (median 2.5 micromol/l; range, < 0.05-188.9 micromol/l). Median urine iodine in 97 samples was 82.2 micromol/l (range, 10.3-417.1 micromol/l). Perchlorate was detectable in all 97 urine samples (median 2.6 micromol/l; range, 0.2-160.6 micromol/l). Colostrum iodine content was not significantly correlated with levels of colostrum perchlorate or concentrations per litre of urinary iodine, perchlorate, or cotinine. Colostrum perchlorate concentrations were not significantly associated with urinary iodine, perchlorate, or cotinine levels. Urinary cotinine levels were not significantly associated with urinary iodine or perchlorate levels. There was no association between maternal urinary iodine and urinary perchlorate levels.
  
  
  CONCLUSIONS
  Iodine is present in human colostrum and thus available for breastfeeding infants immediately after birth. Perchlorate was also present in 93% of samples measured, but the concentrations did not correlate with colostrum iodine concentrations.
authors.affiliation: Section of Endocrinology, Diabetes and Nutrition, Boston Medical Center and Boston University School of Medicine, Boston, MA 02118, USA.
authors.forename: Angela M
authors.initials: AM
authors.lastname: Leung
authors.forename: Elizabeth N
authors.initials: EN
authors.lastname: Pearce
authors.forename: Tara
authors.initials: T
authors.lastname: Hamilton
authors.forename: Xuemei
authors.initials: X
authors.lastname: He
authors.forename: Sam
authors.initials: S
authors.lastname: Pino
authors.forename: Anne
authors.initials: A
authors.lastname: Merewood
authors.forename: Lewis E
authors.initials: LE
authors.lastname: Braverman
mesh_terms: D000293:Adolescent; D000328:Adult; D001900:Boston; D001942:Breast Feeding; D003126:Colostrum / Q000378:metabolism*; D003367:Cotinine / Q000652:urine; D003404:Creatinine / Q000652:urine; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007455:Iodine / Q000378:metabolism*; D010472:Perchlorates / Q000378:metabolism*; D049590:Postpartum Period / Q000378:metabolism*; D012907:Smoking / Q000378:metabolism; D055815:Young Adult
chemical_list: D010472:Perchlorates; D007455:Iodine; D003404:Creatinine; D003367:Cotinine; C494474:perchlorate