Environmental arsenic exposure and its toxicological effect on thyroid function: a systematic review

Abstract Objectives This study was performed to review epidemiological evidence related to Arsenic (As) effects on the thyroid function by focusing on the serum thyroid hormone concentration. Content As, one of the main pollutants, has been recognized as an endocrine-disrupting agent that may affect the function of thyroid as shown by experimental studies. Summary This systematic study indicates the association between As exposure and thyroid dysfunction. The studies have shown an association between serum and urine concentration of arsenic and thyroid dysfunction. Most of them reported the association between increase in the serum or urine As levels and decrease in the triiodothyronine (T3) and thyroxine (T4), and also elevation in the thyrotropic hormone (TSH) levels. Outlook Our findings related to the effects of As on the function of thyroid in humans are still limited and future studies should be done to address this question.