A chemical used in explosives, fireworks and rocket fuel has been found in powdered baby formula in the United States, the Environmental Working Group (EWG) non-profit group said Friday.
In "little-noticed findings", researchers at the US Centers for Disease Control and Prevention (CDC) found that 15 brands of baby milk contained perchlorate, an oxidizer in solid fuels used in explosives, fireworks, road flares and rocket motors, the EWG said.
"Studies have established that the chemical is a potent thyroid toxin that may interfere with fetal and infant brain development," it said.
The two most tainted brands had a nearly 90-percent share of the US powdered baby milk market in 2000, EWG cited the CDC researchers as saying.
The CDC scientists submitted a report of their study on perchlorate in baby formula to the Journal of Exposure Science and Environmental Epidemiology in October last year and it was published last month.
It was unclear when the study was conducted, and the lead researcher, Dr Joshua Schier, was not immediately available for comment.
"The little-noticed CDC findings ... raise new concerns about perchlorate pollution, a legacy of Cold War rocket and missile tests," the EWG said.
According to the EWG, perchlorate is found in drinking water in more than half the 50 US states and mixing tainted baby formula with the contaminated water "could boost the resulting mixture?s toxin content above the level the Environmental Protection Agency (EPA) considers safe."
A study conducted in 2006 by the CDC found that exposure to perchlorate at levels "considerably below" the level considered safe by the EPA altered thyroid hormone levels in women, the EWG said, calling for new limits to be set for perchlorate in drinking water.
Under president George W. Bush, the EPA last year determined that regulating perchlorate levels in drinking water would not result in "a meaningful opportunity for health risk reduction."