CO-occurring exposure to perchlorate, nitrate and thiocyanate alters thyroid function in healthy pregnant women.
Environ Res
; 143(Pt A): 1-9, 2015 Nov.
Article
en En
| MEDLINE
| ID: mdl-26408806
ABSTRACT
BACKGROUND:
Adequate maternal thyroid function during pregnancy is necessary for normal fetal brain development, making pregnancy a critical window of vulnerability to thyroid disrupting insults. Sodium/iodide symporter (NIS) inhibitors, namely perchlorate, nitrate, and thiocyanate, have been shown individually to competitively inhibit uptake of iodine by the thyroid. Several epidemiologic studies examined the association between these individual exposures and thyroid function. Few studies have examined the effect of this chemical mixture on thyroid function during pregnancyOBJECTIVES:
We examined the cross sectional association between urinary perchlorate, thiocyanate and nitrate concentrations and thyroid function among healthy pregnant women living in New York City using weighted quantile sum (WQS) regression.METHODS:
We measured thyroid stimulating hormone (TSH) and free thyroxine (FreeT4) in blood samples; perchlorate, thiocyanate, nitrate and iodide in urine samples collected from 284 pregnant women at 12 (±2.8) weeks gestation. We examined associations between urinary analyte concentrations and TSH or FreeT4 using linear regression or WQS adjusting for gestational age, urinary iodide and creatinine.RESULTS:
Individual analyte concentrations in urine were significantly correlated (Spearman's r 0.4-0.5, p<0.001). Linear regression analyses did not suggest associations between individual concentrations and thyroid function. The WQS revealed a significant positive association between the weighted sum of urinary concentrations of the three analytes and increased TSH. Perchlorate had the largest weight in the index, indicating the largest contribution to the WQS.CONCLUSIONS:
Co-exposure to perchlorate, nitrate and thiocyanate may alter maternal thyroid function, specifically TSH, during pregnancy.Palabras clave
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Tiocianatos
/
Glándula Tiroides
/
Percloratos
/
Exposición Materna
/
Disruptores Endocrinos
/
Nitratos
Tipo de estudio:
Observational_studies
/
Prevalence_studies
/
Risk_factors_studies
Límite:
Adolescent
/
Adult
/
Female
/
Humans
/
Pregnancy
País/Región como asunto:
America do norte
Idioma:
En
Revista:
Environ Res
Año:
2015
Tipo del documento:
Article