SAN FRANCISCO (KCBS / CBS 5) — 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.
KCBS’ Tim Ryan and Doug Sovern Report:
As a result, Bay Area residents are not at risk of radiation contamination, both regional and federal authorities reassured the public on Thursday.
A CBS 5 poll of Bay Area residents found a majority, 54%, were not very concerned or not at all concerned about radiation from Japan reaching us. The poll also found that 71% said they would not be buying potasium iodide, a substance that helps keep the body from absorbing radiation. It’s sales have soared in recent days in the Bay Area because of radiation fears.
State health officials have advised residents not to take potassium iodide as a precautionary measure, saying “it is not necessary given the current circumstances in Japan.”
Residents near the Fukushima Daiichi Nuclear Power Station in Japan have been evacuated since the plant was crippled by last week’s deadly 9.0-magnitude earthquake and ensuing tsunami, and models show that a radioactive plume from the plant could reach California on Friday.
“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, even though the facility didn’t have a containment
building and used graphite fuel that ignited and burned.
“You could have a plume, but it’s a big area and a big volume,” Kemper said.
In this case, United Nations experts believe the plume from Japan will be so diluted that it poses no health consequences in the U.S.
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.
The U.S. Environmental Protection Agency, Nuclear Regulatory Commission and Department of Health and Human Services have all said California residents are not expected to be at risk.
“Everybody, for the most part, is saying the risks are insignificant,” said Eric Stevenson, director of technical services for the Bay Area Air Quality Management District. “It would have to be a major catastrophe for us to be significantly impacted. Most of these impacts will, unfortunately for the Japanese, be localized.”
The air quality district operates a radiation detector for the EPA at its San Francisco facility, and the detector has not reported elevated levels of radiation, Stevenson said.
Also Thursday, the South Coast Air Quality Management District said there had been no change in background levels of radiation detected at three Southern California sites that it operates for the EPA.
Still, the U.S. government has implemented several policies out of “an abundance of caution” to reassure and protect residents.
The EPA, whose California monitoring stations include locations in San Jose and Richmond, has set up additional stations in Guam, Alaska and Hawaii.
U.S. Customs and Border Protection has directed its employees to specifically monitor maritime and air traffic from Japan for possible radiation contamination.
So far no planes entering the U.S. have tested positive for harmful levels of radiation, and travelers are being observed for signs of radiation sickness, according to the agency.
Mail and cargo are also being tested, and anything that could be cause for alarm will be denied entry to the country, agency officials said.
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