“…Human exposure to perchlorate is associated with potential health effects because this anion competes with iodine's transport into the thyroid gland by the sodium/iodide symporter (NIS) and can prevent the uptake of iodine into the thyroid, which is essential for thyroid hormone synthesis, normal development, growth, and metabolism (Eguchi et al, 2014;Srinivasan and Viraraghavan, 2009). NIS is expressed in human placenta and in lactating breast tissue, likely as a mechanism for active transport of iodide to the fetus (Bannerman et al, 2006;Dohan and Carrasco, 2003;Logothetopoulus and Scott, 1956). Several studies (Bannerman et al, 2006;Dohan et al, 2007;Tran et al, 2008) found that perchlorate is actively transported across membrane barriers by NIS, raising concerns about the active transport of perchlorate into the fetal circulation during pregnancy and into breast milk (Gu and Coates, 2006;ITRC, 2005;Mantus, 2005), providing two successive routes of exposure during pre-and postnatal periods, respectively.…”