ABC News Report
Perchlorate, a chemical used in rocket fuel, is turning up in the nation's food -- in vegetables like lettuce and spinach -- and water supply.
You've never heard of it? Most Americans haven't, but millions have been exposed to it. This week Congress held hearings to determine just how dangerous it is to humans' health.
"A study from the Centers for Disease Control last year tested almost 3,000 people who are representative of the U.S. population. They found perchlorate in every single person," said Dr. Anila Jacob of the Environmental Working Group.