After the Sept. 11, 2001 terror attacks on New York and Washington, Los Angeles traffic reporters could be heard ruminating about the effect of the East Coast attacks on West Coast drivers' behavior. One reporter said LA drivers were being “much more considerate” than usual.

Now Californians are fearful that damage to Japanese nuclear power plants will leave them dusted with harmful amounts of radiation. That's creating a land rush business for the few U.S. manufacturers of potassium iodide.

Potassium iodide is administered to protect the thyroid gland from radiation poisoning when one is exposed to high doses of radiation. It blocks absorption of harmful radioactive iodine.

But is this really necessary in California? Health officials say no and caution that there is a risk of side effects in people who are allergic to shellfish or who have existing thyroid problems.

One public health official noted that Japan has evacuated residents who live within 12 miles of the troubled nuclear plants. The West Coast of the United States is more than 5,000 miles from Japan, which would seem to minimize the risk of harm, he noted.

The Wall Street Journal reported that fearful Americans had bought up nearly all of the existing supplies of potassium iodide from companies such as Anbex Inc., of Williamsburg, Va.

"Those who don't get it are crying.  They're terrified," a company official said.