Additional Human Health Studies on Perchlorate Unveiled
NAS Perchlorate Panel Hears Latest Findings From Experts

Contact:   Perchlorate Information Bureau     (916) 448-3152

May 25, 2004

Woods Hole, MA - New research on the effects of perchlorate on pregnant women, infants and adults was presented to a special panel of the National Academy of Sciences (NAS) yesterday, with preliminary findings suggesting that perchlorate levels ranging from non-detect to 110 parts per billion (ppb) have no effect on pregnant women and infants, and that perchlorate with levels as high as 10,000 ppb has no effect on healthy adults.

The preliminary findings were presented by John Gibbs, M.D., vice president of Health Management and Corporate medical director, Kerr-McGee Corporation, and Jonathan Borak, M.D., Associate Clinical Professor of Medicine & Epidemiology, Yale University, working with the Perchlorate Information Bureau. Summaries of the reports are as follows:

• "Chronic Environmental Exposure to Perchlorate in Drinking Water and Thyroid Function During Pregnancy and Neonatal Period." The study found no impacts from perchlorate on the mothers during the critical period between the late first and early second trimesters, and no effect on fetal development or thyroid levels in newborns. The study examined pregnant women and babies from three cities in Chile, where perchlorate levels range from non-detect to 110 ppb, and daily intake of dietary iodide is equivalent with the U.S. Tellez, et al., 2004.
• "The Effect of Perchlorate, Thiocyanate and Nitrate on Thyroid Function in Long-Term Workers Exposed to Perchlorate." The study found that long-term, intermittent high exposure to perchlorate does not induce hypothyroidism or goiter in adults. The study examined 29 healthy adult males in Cedar City, Utah, who had been working in perchlorate production for at least two years, with 50 percent of the subjects having worked in perchlorate production for more than six years. Exposure to perchlorate was through ingestion and inhalation, and median exposure levels were equivalent to 10,000 ppb. Braverman, et al., 2004.

The Perchlorate Information Bureau is supported by a subset of the member companies of the Perchlorate Information Bureau, including Lockheed Martin, Aerojet, Kerr-McGee Chemical and American Pacific Corporation. In the past decade, the Perchlorate Information Bureau has worked cooperatively with the U.S. Environmental Protection Agency to increase scientific and medical understanding of perchlorate's risk to human health.

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