Thyroid disruption at birth due to prenatal exposure to beta-hexachlorocyclohexane.
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.
Alvarez-Pedrerol
Mar
M
Centre for Research in Environmental Epidemiology-IMIM, Barcelona, Spain. malvarez1@imim.es
Ribas-Fitó
Núria
N
Torrent
Maties
M
Carrizo
Daniel
D
Garcia-Esteban
Raquel
R
Grimalt
Joan O
JO
Sunyer
Jordi
J
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*
D001556:Hexachlorocyclohexane; D013972:Thyrotropin; D011078:Polychlorinated Biphenyls; C023888:beta-hexachlorocyclohexane; C014024:2,4,5,2',4',5'-hexachlorobiphenyl