title: Thyroid disruption at birth due to prenatal exposure to beta-hexachlorocyclohexane.
abstract: OBJECTIVE
  Thyroid hormones play an important role in human brain development, and some organochlorine compounds (OCs) act as thyroid disruptors. The objective of the present study was to evaluate the association between prenatal exposure to organochlorine compounds and thyroid function in newborns from a general population birth cohort in Menorca, with an a-priori specific focus on beta-HCH.
  
  
  METHODS
  Levels of polychlorinated biphenyls (PCB congeners 28, 52, 101, 118, 138, 153 and 180), hexachlorobenzene (HCB), beta-hexachlorocyclohexane (beta-HCH), dichlorodiphenyl dichloroethylene (p'p'-DDE) and dichlorodiphenyl trichloroethane (p'p-DDT) in cord serum, and thyrotropin (TSH) concentration in plasma three days after birth were measured in 387 newborns from Menorca. The TSH concentration was categorized (high or low), except for 27 children whose TSH levels were quantified.
  
  
  RESULTS
  Levels of beta-HCH and PCB-153 were positively related to TSH concentrations (gestational age-adjusted coefficient (p-value): 0.26 (p = 0.006) and 0.31 (p = 0.050), respectively).
  
  
  CONCLUSIONS
  beta-HCH is potentially a new thyroid disrupting compound, deserving special interest in future studies given its high body burden in humans.
authors.affiliation: Centre for Research in Environmental Epidemiology-IMIM, Barcelona, Spain. malvarez1@imim.es
authors.forename: Mar
authors.initials: M
authors.lastname: Alvarez-Pedrerol
authors.forename: Núria
authors.initials: N
authors.lastname: Ribas-Fitó
authors.forename: Maties
authors.initials: M
authors.lastname: Torrent
authors.forename: Daniel
authors.initials: D
authors.lastname: Carrizo
authors.forename: Raquel
authors.initials: R
authors.lastname: Garcia-Esteban
authors.forename: Joan O
authors.initials: JO
authors.lastname: Grimalt
authors.forename: Jordi
authors.initials: J
authors.lastname: Sunyer
mesh_terms: D015331:Cohort Studies; D005260:Female; D001556:Hexachlorocyclohexane / Q000633:toxicity*; D006801:Humans; D007231:Infant, Newborn; D011078:Polychlorinated Biphenyls / Q000633:toxicity; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects / Q000097:blood*; D013030:Spain; D013961:Thyroid Gland / Q000187:drug effects*; D013972:Thyrotropin / Q000097:blood*
chemical_list: D001556:Hexachlorocyclohexane; D013972:Thyrotropin; D011078:Polychlorinated Biphenyls; C023888:beta-hexachlorocyclohexane; C014024:2,4,5,2',4',5'-hexachlorobiphenyl