Vanderbilt researchers have discovered that perchlorate, an environmental pollutant found in many sources of drinking water in the U.S., inhibits the uptake of iodide, an essential component of thyroid hormones, in a more pronounced and fundamental way than commonly considered. This discovery was published May 25 in the journal Nature Structural & Molecular Biology just as the Environmental Protection Agency (EPA) announced its decision to not regulate the levels of perchlorate in drinking water.
Dr. Nancy Carrasco, professor and chair of the Department of Molecular Physiology and Biophysics, and the paper’s leading author believes it’s a decision that may endanger public health in many communities across the U.S. According to the EPA perchlorate is a naturally occurring chemical compound found in the arid regions of the U.S., in fertilizer deposits in Chile, and in potash ore in the U.S. and Canada. The chemical is used to manufacture rocket fuel and explosives. Because perchlorate dissolves easily and is mobile in water, it is frequently detected in water supplies near sites where rocket fuel is used or made.
The first author of the paper is graduate student Alex Llorente-Esteban. Research instructor Andrea Reyna-Neyra, Ph.D. also participated in the study. The Carrasco laboratory and their collaborators have previously shown that NIS has at least a ten-times greater affinity for perchlorate than for iodide – meaning that if there were equal concentrations of iodide and perchlorate in the bloodstream the protein would bring perchlorate into the thyroid in far greater quantities than iodide.
Source: Vanderbilt University
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