Gestational Exposure to Chromium Interferes with Post-Natal Development and Growth of the Thyroid Gland through Altered TSH

Chromium is one of the important heavy metal toxicants released into the environment by about 50 industries, which includes leather tanneries, stainless steel welding, and ordinance factory and chrome platting. Though the adverse effect of chromium on skin, lung and reproductive organs are known, its toxic effect on endocrine glands is little known. It is well known that chromium can readily pass through the placental barriers to reach the growing foetus. Recent studies attest the embryo toxicity of gestational exposure to chromium. The thyroid is one of the earliest endocrine organs to develop from the endoderm and its development is regulated by specific transcription factor like TTF-1, TTF-2, Pax-8 and various other growth factors.