OCTOBER 30, 2006

10:33 AM


CONTACT: Environmental Working Group

Bill Walker, 510-444-0973 x301

EWG Public Affairs, (202) 667-6982

WASHINGTON – October 30 – Exposure to a rocket fuel chemical widespread in the U.S. drinking water and food supply, at levels equal to or lower than national and state standards, could cause thyroid deficiency in more than 2 million women of childbearing age who would require medical treatment to protect their unborn babies, according to an Environmental Working Group (EWG) analysis of new data from the U.S. Centers for Disease Control.

At a hearing in Sacramento today, California health officials will consider a proposed standard for perchlorate in drinking water that EWG found could trigger thyroid deficiency requiring treatment during pregnancy in more than 272,000 California women. New Jersey’s proposed standard could cause such a deficiency in 65,000 women in that state.

If applied nationwide, the level proposed in California could cause thyroid deficiency requring treatment during pregnancy in more than 2.2 million women of childbearing age. The federal government has no perchlorate drinking water standard, but its standard for cleanup of hazardous waste sites is more than four times weaker than the California drinking water proposal, extending the risk to millions of additional women and their babies.

EWG’s study, available at, shows that the perchlorate cleanup standard adopted by the U.S. Environmental Protection Agency, and the safety standards for perchlorate in drinking water under consideration in California and New Jersey, are inadequate to protect the 22 million American women of childbearing age who don’t get enough iodine in their diet. Even the stricter drinking water standard already adopted by Massachusetts would cause a decline in women’s thyroid levels.

“In light of what we now know from the Centers for Disease Control data, California’s proposed standard is inadequate to protect public health,” said EWG scientist Anila Jacob, M.D., who will present the group’s findings at the hearing today. “State and federal standards should reflect the fact that exposure to even low levels of perchlorate could place a significant number of women of childbearing age at increased risk of thyroid deficiency, and if they became pregnant, they would need treatment to protect their unborn children.”

Perchlorate, the explosive ingredient in solid rocket fuel, has leaked from military bases and defense and aerospace contractors’ plants in at least 22 states, contaminating drinking water for millions of Americans. The chemical has also been found widely in supermarket milk, produce and many other foods, and in a separate study, the CDC found it in the urine of every person tested. As small changes in thyroid hormone levels during pregnancy €” even within the normal range €” are associated with decreased intellectual and learning capacity in childhood, the extensive reach of perchlorate contamination has huge implications for public health.

Earlier this month, a startling study from the Centers for Disease Control found that in the 36 percent of U.S. women with low iodine intake, almost any amount of perchlorate exposure was linked to a significant change in levels of thyroid hormones. For about 1 in 10 of these women, if they were exposed to 5 parts per billion of perchlorate in drinking water, the resulting hormone disruption would require treatment during pregnancy for sub-clinical hypothyroidism, according to a consensus of clinical endrocinologists.

Under pressure from the Pentagon and the defense industry, EPA has delayed setting a national drinking water standard for perchlorate. But earlier this year, after a controversial National Academy of Sciences study €” since strongly criticized by a federal advisory panel on children’s health €” the EPA adopted a standard for cleanup of perchlorate-contaminated waste sites of 24.5 parts per billion.

California is in the final stages of adopting a perchlorate drinking water standard of 6 ppb, recommended by state scientists before release of the CDC study. The proposed standard in New Jersey is 5 ppb. In July, Massachusetts adopted 2 ppb as the nation’s first legally enforceably drinking water standard.