Perchlorate, a tasteless, colorless component of solid rocket fuel, has been detected in the drinking water of 26 states. Despite its toxicity, it is not yet regulated.
However, the Environmental Protection Agency’s Office of
Water is considering new drinking water standards for the dangerous
salt, following a recent National Academy of Sciences report. The
EPA had previously estimated that a safe dose was 1 part per
billion. But in February, based on the report’s findings, the
agency raised that number to 24.5 parts per billion.
Critics cite two problems with the new number: It ignores
perchlorate exposure from food, and it is based on adult bodyweight
and water consumption, although children face the greatest risks.
"I thought it was a bit reckless," says Dr. Gina Solomon,
senior scientist with the Natural Resources Defense Council.
Perchlorate disrupts iodine intake and thyroid function.
In adults, the thyroid gland regulates metabolism, but in
developing infants, low levels of thyroid hormone can cause
cretinism — a severe form of mental retardation.
During the Cold War, large-scale missile production inundated
military sites with perchlorate (HCN, 4/28/03: Perchlorate:
it’s not just for rocket fuel anymore). Specific regulations
for cleanup efforts do not currently exist, but the study will
provide guidelines, says Suzanne Ackerman, an EPA spokesperson.
Dissatisfied with the lack of federal regulation, some
states are taking action on their own. California plans to enforce
drinking water standards of 6 parts per billion by the end of this
year. "None of us should have to drink perchlorate," says Renee
Sharp of the Washington, D.C.-based Environmental Working Group.
"The stuff is rocket fuel."