Impact of essential and toxic trace metals on thyroid health and cancer: A review

Most investigations conducted in the last four decades have shown a rising incidence of thyroid diseases worldwide. Although our knowledge of the molecular pathways of thyroid disease has advanced, the initial steps in thyroid cancerogenesis have not yet been sufficiently elucidated. However, recent human biomonitoring studies have shown that specific trace metals, as major endocrine disrupters, could be considered as risk factors for impaired thyroid health and the evolution of thyroid cancer (TC). In this review, the impact of essential and toxic trace metals from the environment on thyroid health and TC was evaluated. Furthermore, this review clarifies which trace metals most likely contribute to the etiology of TC. Biomarkers based on trace metal ratios are proposed. Overall, the information described in this review is expected to be useful in planning future fundamental and applied studies on the endocrine toxicity of essential and toxic trace metals. © 2021, The Author(s), under exclusive licence to Springer Nature B.V