CDC chief: Americans not at risk from radiation

Minuscule amounts of radiation detected in the United States do not pose any risk to Americans' health, Centers for Disease Control and Prevention Director Dr. Thomas Frieden reiterated Tuesday.

"We do not expect radiation to reach problematic levels," he said on a conference call with reporters.

Despite a low-level of concern, Frieden said, agencies such as the CDC, the Food and Drug Administration, the Environmental Protection Agency and the U.S. Department of Agriculture were all actively monitoring the air, the food and the water supplies in the U.S. for any evidence of contamination.

Dr. William Jones, acting director for the FDA's division of food safety, echoed Frieden's sentiments.

"There is a great deal of monitoring going on for any product that comes into this country," said Jones. "Anything contaminated to level where it could pose a concern would be detected."

Also at issue on Tuesday's call: Whether Americans should be taking or stockpiling potassium iodide pills.

"I understand that there are a lot of people who want to have [the pills]," Frieden said, "But I want to say unequivocally that there is no reason for anyone in the U.S. to take potassium iodide pills at this time."

Potassium iodide pills (also known as KI pills) can be helpful for people in the immediate vicinity of a nuclear accident, by preventing the thyroid gland from taking in radioactive iodine. However, KI pills only protect the thyroid and are not recommended for wider consumption, Frieden said, due to the inherent health risks associated with taking the pills, such as allergic reactions, stomach upset, inflammation of the salivary glands and certain thyroid conditions.

"Potassium iodide is part of the broader strategy on how we would prepare for exposure in the event of significant incident," he said, "but we don't anticipate any scenario where we would need potassium iodide in the U.S. from the incident in Japan."

Frieden and his colleagues at the FDA went on to say that there are no devices or pills that can protect the entire body from radiation, despite claims made by some online retailers.

"There is nothing that is currently approved as a silver bullet," said Patricia Hansen, a senior scientist at the FDA. "Those claims are fraudulent."