Infants in the USA exposed to unsafe levels of thyroid-damaging perchlorate. 11/09

Researchers from the Centers for Disease Control and Prevention (CDC) have found that 15 brands of powdered infant formula are contaminated with perchlorate, a rocket fuel component detected in drinking water in 28 states and territories of the USA. Although no brands were identified, the two most contaminated, made from cow’s milk, accounted for 87% of the US powdered formula market in 2000.

The CDC findings, published in the March 2009 edition of the Journal of Exposure Science and Environmental Epidemiology, raise new concerns about perchlorate pollution, a legacy of Cold War rocket and missile tests, as studies have established that the chemical is a potent thyroid toxin that may interfere with fetal and infant brain development.

The study suggested that reconstituting infant formula with water contaminated with perchlorate at just 4 parts per billion would cause 54% of the infants consuming the mix to exceed the so-called “safe” dose set by the Environmental Protection Agency (EPA), a level which many scientists believes is already too high to protect public health.

While these findings are of concern, the CDC also noted that FDA (in the US) requires infant formula to be supplemented with iodine, a nutrient that can counteract the negative effects of perchlorate on the thyroid gland. The range of required iodine concentrations in formula is between 5 and 75 micrograms per 100kcal of energy. At 75 micrograms this could offer some protection but infants consuming formula with lower iodine levels would remain vulnerable to the toxic effects of the perchlorate.

These findings underscore the need for the EPA, who, last year, declared that perchlorate in drinking water posed no threat and neednot be regulated, to scrap Bush era perchlorate policies that shielded defense contractors and other big polluters from the costs of cleaning up perchlorate-contaminated water by setting a legally enforceable safe drinking water level that protects pregnant women, infants and others who are most vulnerable to the effects of this harmful chemical.

In response to criticisms from scientists, health professionals and consumer advocates, in January 8, EPA issued a non-binding “health advisory” on perchlorate and asked the National Academy of Sciences to review the issue.
Years of federal inaction have prompted some states to set their own mandatory limits for perchlorate in drinking water: California, at 6 ppb and Massachusetts at 2 ppb. While recent scientific research has shown these standards to be too weak to protect public health adequately, they are far more stringent than EPA’s action in January.
At her confirmation hearing, EPA administrator Lisa Jackson pledged that she would act “immediately” to reduce perchlorate contamination in drinking water.
Since then, EWG has called on Jackson to fulfill that promise, but so far the agency has not made public a plan of action.

The new CDC study provides some of the strongest evidence yet that a legally enforceable safe drinking water level for perchlorate should be a priority for the Obama administration.


For a fuller report including useful Q&A, a time line for perchlorate and advice as to how to remove it from your water

First Published in November 2009

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