Low-Level Radioactive Particles To Reach California By Friday

SAN FRANCISCO (KCBS) — Wind patterns will bring a radioactive plume from the crippled Japanese nuclear reactors to the Aleutian Islands by Thursday and to the West Coast by Friday, according to projections.

However, the low-level radioactive particles fall well within safe limits and pose little health risk, according to experts with the Comprehensive Test Ban Treaty Organization.

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"What really matters is the altitude that the plume is at," said Dr. Kirby Kemper, a physicist at Florida State University.

Radioactive particles from Chernobyl that reached the United States stayed at such a high altitude that very little was deposited on the surface, he said.

"You could have a plume, but it's a big area and a big volume."

In this case, United Nations experts believe the plume will be so diluted that it poses no health consequences in the U.S.

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The projections are based on 63 sensors operated internationally by the United Nations and 100 radiation monitors the U.S. Environmental Protection Agency operates across North America.

The predicted path could change depending on shifting weather patterns.

It took nearly two weeks for a radioactive plume from a 2006 North Korean nuclear test to travel across the pacific, according to the United Nations.