FRIDAY, March 18 (HealthDay News) -- Trace amounts of radiation
apparently from the crippled nuclear power plant in Japan have
started to reach California, but they pose no health risks,
according to news reports.
A diplomat with access to radiation tracking by the United
Nations' Comprehensive Test Ban Treaty Organization told the
Associated Press that initial readings are "about a billion
times beneath levels that would be health threatening." The
diplomat spoke on the condition of anonymity because the
organization doesn't make its findings public, the news service
Federal officials and radiation experts in the United States
insist there's no threat to public health from the radiation plume,
but they are still closely monitoring the situation with detection
monitors along the West Coast, the
The chances of any radioactive plume reaching the United States
are "close to zero," Jacqueline Williams, program director for
radiation medicine at the University of Rochester Medical Center's
Center for Biophysical Assessment and Risk Management Following
HealthDay earlier this week.
"Obviously, what's happening [in Japan] is changing from moment to moment," Williams added, "but there seems to be very little in the way to fear."
Levels of radioactivity that have already been released in Japan
"are very much dissipated, so by the time it gets to California or
the U.S., it would be extremely low levels," agreed Barry
Rosenstein, a professor of radiation oncology at Mt. Sinai School
of Medicine in New York City.
The reason for that, simply, is that "Japan is a long way away,"
said Williams, who's also vice president of the Radiation Research
While considerable amounts of radiation have escaped from the
four damaged reactors in Japan -- and with experts predicting much
more, perhaps soon -- any of that radiation would have to travel by
air to North America, more than 5,000 miles away.
During that journey, said Williams, any radioactivity in the air
would be dispersed and therefore greatly weakened.
"Just the sheer dilution factor, whether by water [nuclear plant workers in Japan have been flooding the damaged reactors with seawater in an effort to cool them] or air, it's not going to affect anyone here," she said.
And that would probably hold true "even if they [the Japanese]
had the most catastrophic event, like a Chernobyl [in 1986 in the
Ukraine] and you had a large amount of radioactivity being
released," Williams added.
Also, heavier radiation particles would fall out of a
radioactive plume, so "by the time anything reached us it would be
no more than we experience normally," she said. "Everyone is being
irradiated all the time."
This so-called "background" radiation isn't harmful and comes
from sources in the Earth, solar rays in the atmosphere, and even
But it's not inconceivable that the health risk in the United
States might have to be reassessed if the Japan disaster reached
catastrophic proportions, Rosenstein said.
"In harkening back to Chernobyl, where there was a tremendous release of radioactive isotopes, it did affect a good portion of Europe, certainly well beyond the Chernobyl area," he said.
Still, he pointed out, Europe and the Ukraine are much closer to
each other than are Japan and the United States, even when talking
about Hawaii or Alaska.
At this point, however, there is "no concern" about harmful
effects from radioactivity this side of the Pacific, Rothstein
The Nuclear Regulatory Commission concurs. All the available
information indicates that "weather conditions have taken the small
releases from the Fukushima reactors out to sea away from the
population. Given the thousands of miles between the two countries,
Hawaii, Alaska, the U.S. Territories and the U.S. West Coast are
not expected to experience any harmful levels of radioactivity,"
the agency said on its Web site.
Still, not everyone is so sanguine.
Dr. Ira Helfand, a Massachusetts-based nuclear safety expert and
past-president of Physicians for Social Responsibility, told
CBS News earlier this week that if fuel at one of the four
crippled reactors in Japan were to melt down and break through the
containment vessel, it could cause a massive explosion as
superheated fuel mixed with the water coolant.
"The fuel rods contain enormous amounts of radioactive material -- each reactor can release more radiation than 1,000 Hiroshima-sized bombs," Helfand told the network.
He said it's not clear just how far radiation from such an
accident would spread -- and what the potential health threats
"At Chernobyl, it spread over large areas of Europe, and significant areas up to 100 miles downwind needed to be abandoned," he said. "But the conditions were somewhat different, and we aren't sure how far the radiation will be distributed this time."
For more on the risks of nuclear radiation, visit the
University of Pittsburgh.