Perchlorate Fact Sheet

Perchlorate is both a naturally occurring as well as a man-made inorganic chemical. Perchlorate is an oxidizer used in the manufacturing of fireworks, explosives, and other pyrotechnics. In the United States, contamination of soil and water is found predominantly in areas where the manufacture, use, and storage of munitions and rocket propellants took place over the last 50 years. The US General Accounting Office (GAO) determined perchlorate had contaminated groundwater at the locations where the chemical had been stored. Food crops and vegetables grown on contaminated soils may show higher concentrations of perchlorate. Total ingestion of perchlorate thus consists of that due to food and that due to drinking water. Perchlorate can also be formed as a byproduct of in situ chlorine synthesis also using ozone such as sea water aquariums and swimming pools. Perchlorate inhibits the absorption of iodine by the thyroid gland which results in decreased secretion of certain thyroid hormones causing a condition called Hypothyroidism. Prolonged Hypothyroidism is known to lead to developmental and learning disabilities in infants and children.