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Updated: May 20, 2026
04:14
In vivo Characterization of Endocrine Disrupting Chemical Effects via Thyroid Hormone Action Indicator Mouse
Published on: October 6, 2023
Environmental perchlorate and thiocyanate exposures and infant serum thyroid function
Angela M Leung1, Lewis E Braverman, Xuemei He
1Section of Endocrinology, Diabetes, and Nutrition, Boston University School of Medicine, 88 East Newton St., Boston, MA 02118, USA. angela.leung@bmc.org
Summary
This study found that common environmental exposures like perchlorate and thiocyanate do not negatively impact thyroid function in breastfed infants. Iodine levels were sufficient in Boston-area mothers and their babies, easing concerns about these specific environmental factors.
Area of Science:
- Endocrinology
- Environmental Health
- Pediatrics
Background:
- Breastfed infants require maternal iodine for crucial neurodevelopment via thyroid hormone production.
- Iodine sufficiency in US childbearing women may be inadequate, raising concerns for infant health.
- Ubiquitous environmental perchlorate and thiocyanate can inhibit iodine uptake, potentially affecting thyroid function.
Purpose of the Study:
- To assess the relationship between environmental perchlorate and thiocyanate exposure and infant thyroid function.
- To determine if these environmental contaminants impact iodine availability for breastfed infants.
- To evaluate infant thyroid-stimulating hormone (TSH) and free thyroxine (FT4) levels in relation to exposure.
Main Methods:
- Cross-sectional study of 64 Boston-area mother-infant pairs (infants 1-3 months old).
- Measured iodine, perchlorate, and thiocyanate in breast milk, maternal urine, and infant urine.
- Analyzed correlations between contaminant levels and infant serum TSH and FT4.
Main Results:
- No significant correlations were found between infant TSH or FT4 and iodine, perchlorate, or thiocyanate levels.
- Perchlorate and thiocyanate levels in breast milk, maternal urine, and infant urine did not predict infant thyroid function.
- Boston-area mothers and infants in the study demonstrated sufficient iodine levels.
Conclusions:
- Maternal and infant exposure to environmental perchlorate and thiocyanate does not appear to affect infant thyroid function.
- The study suggests that iodine sufficiency is generally maintained in this population despite ubiquitous exposures.
- Concerns regarding the impact of these specific environmental contaminants on infant thyroid health are not supported by these findings.
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