Perchlorateâ€"a powerful oxidant used in solid rocket fuels by the military and aerospace industryâ€"has been detected in public drinking water supplies of over 11 million people at concentrations of at least 4 parts per billion (ppb). High doses of perchlorate can decrease thyroid hormone production by inhibiting the uptake of iodide by the thyroid. Thyroid hormones are critical for normal growth and development of the central nervous system of fetuses and infants. This report evaluates the potential health effects of perchlorate and the scientific underpinnings of the 2002 draft risk assessment issued by the U.S. Environmental Protection Agency (EPA). The report finds that the body can compensate for iodide deficiency, and that iodide uptake would likely have to be reduced by at least 75% for months or longer for adverse health effects, such as hypothryroidism, to occur. The report recommends using clinical studies of iodide uptake in humans as the basis for determining a reference dose rather than using studies of adverse health effects in rats that serve as EPA's basis. The report suggests that daily ingestion of 0.0007 milligrams of perchlorate per kilograms of body weightâ€"an amount more than 20 times the reference dose proposed by EPAâ€"should not threaten the health of even the most sensitive populations.

This is a print on demand edition of a hard to find publication. Perchlorate is both a man-made and naturally occurring chemical used in rocket fuel, explosives, fireworks, and other products. Naturally occurring perchlorate is produced through atmospheric processes and then settles on surface water or land. It can disrupt the uptake of iodide in the thyroid, potentially interfering with thyroid function and negatively affecting fetal and infant brain development and growth. This report examined: (1) what is known about the extent to which perchlorate occurs in the nation's water and food supply and its likely sources; (2) what actions DoD, NASA, and DoE have taken to respond to or lessen perchlorate releases; and (3) what actions states, such as CA and MA, have taken to regulate perchlorate. Charts and tables.