Perchlorate found in infant formula

Samples of powdered infant formula contain trace levels of a rocket fuel ingredient, a federal study has found.

Researchers at the Centers for Disease Control and Prevention tested infant formula for traces of perchlorate because of concerns that the chemical can damage thyroid function. Their findings were published last month in the Journal of Exposure Science and Environmental Epidemiology.

Perchlorate has been found in the drinking water of at least 35 states and the District of Columbia. The chemical can inhibit the thyroid gland's iodine uptake, interfering with fetal development.

The highest levels of perchlorate were found in formulas derived from cow's milk, the researchers found. They also looked at soy-based formulas, as well as formulas from lactose-free cow's milk and synthetic amino acids. They declined to say which brands they tested, but said each one contained detectable levels.

The study does not answer questions about how traces of perchlorate affect human health. Some factors could offset the chemical, including the presence of iodine. An infant's weight and formula consumption can also influence risk.

The researchers also offered several caveats for understanding the results, including the scope of the study. The samples were all taken from one city, meaning the results might not apply nationwide.

But some groups are pointing to the findings as evidence that the government needs to set a more stringent perchlorate health advisory level.

"Infants fed cow's milk-based powdered formula could be exposed to perchlorate from two sources -- tap water and formula," said Anila Jacob, a senior scientist with the Environmental Working Group. "That suggests that millions of American babies are potentially at risk."

Jacob's group is urging U.S. EPA to regulate perchlorate in water. Last year, the agency said it saw no need for such regulations because they would offer no "meaningful opportunity for health risk reduction."

But EPA in January delayed deciding on regulation until the National Academy of Sciences studies the matter.

Senate Environment and Public Works Chairwoman Barbara Boxer (D-Calif.) said in a statement that the CDC study puts further pressure on EPA to set a safe drinking water standard. Boxer introduced legislation last year aimed at limiting the amount of perchlorate in drinking water and requiring some public water systems to monitor it and inform the public of any contamination.

EPA Administrator Lisa Jackson pledged at her Senate confirmation hearing that she would address perchlorate. EPA did not respond to requests today for comment.