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[cdn-nucl-l] FW: Oak Ridger returns from Japan with details of radiation tragedy
> From: Michael C. Baker[SMTP:email@example.com]
> Reply To: Ans-pie
> Sent: Tuesday, November 16, 1999 10:24 AM
> To: Multiple recipients of list ans-pie
> Subject: Oak Ridger returns from Japan with details of radiation
> Oak Ridger returns from Japan with details of radiation tragedy," November
> 1999, By Frank Munger News-Sentinel staff writer,
> "Richard Toohey, a health physicist on the staff at the Radiation
> Assistance Center/Training Site in Oak Ridge, was among a group of
> experts invited to Japan recently for briefings and discussions on the
> Sept. 30
> radiation accident at Tokaimura.
> Three workers at the uranium-processing facility received severe radiation
> in the criticality accident, one of the worst in decades, and they remain
> "They could not be getting better medical care anywhere in the world,"
> said, although he indicated the odds are still against one of the men
> Toohey said there is great uncertainty about the dose estimates, and the
> response is focused on treating the biological effects and trying to
> counter the
> ever-present threat of infection as bodily systems fail.
> The nuclear accident occurred when the men poured a nitrate solution with
> enriched uranium (19 percent U-235) from a safely configured container
> into one
> that was not shaped properly to hold the fissile material. Some of the
> regarding the accident are still the subject of investigation.
> A flash of blue light signaled the start of the fissioning process, and
> initial burst of radiation -- gamma rays and neutrons -- reached the three
> at different angles and in different amounts.
> According to Toohey, the worker (identified as Mr. O) standing on the
> floor and
> holding a funnel over the entry port received the highest radiation dose
> somewhere in the range of 1,200 rads. No one has ever survived that kind
> His co-worker (Mr. S) was on a platform, leaning over the vessel and
> pouring the
> solution through the funnel. He received an estimated dose of 800 to 900
> often a fatal dose as well.
> The third employee (Mr. Y) was in an office about 5 meters away, and his
> was about 300 rads, maybe less.
> All three of the men saw the blue flash, although Mr. Y saw it indirectly
> as a
> reflection in a glass wall.
> Mr. O and Mr. S left the room after seeing the flash and hearing the alarm
> activated by gamma rays. Mr. Y reported the accident by telephone, and
> then he,
> too, ran for safety.
> Toohey said there was no explosion, although there was some release of
> fission products (including krypton and xenon) in the room. And he said
> remains hot because of the fission products left in the container,
> radioactive cesium that's emitting gamma radiation.
> Mr. O lost consciousness almost immediately, which apparently delayed the
> departure of the ambulance from the scene as attendants tried to revive
> The radiation victim now faces a whole host of medical problems, ranging
> kidney failure to huge blisters from the radiation burns.
> His bone marrow was virtually destroyed, and he received a transfusion of
> cells from his sister's blood. He subsequently showed some recovery in
> aspect, but Toohey said Mr. O's long-term survival is very unlikely.
> "If he does, he'll set a new record" for surviving the highest radiation
> Toohey said.
> Mr. S "has a shot" at survival, according to Toohey.
> He received a fetal cord blood transport, which involves cells from a
> that have not yet been imprinted for immunological response.
> These cells reportedly are effective in helping rebuild the bone marrow
> they do not attack the tissues as some foreign cells would.
> Mr. S's blood cell count has shown substantial improvements since the
> transplant, Toohey said.
> Mr. O and Mr. S are in "reverse isolation" at the Japanese hospitals to
> them from coming into contact with potential carriers of infections.
> The third employee, Mr. Y, initially showed a drop in his blood count but
> since recovered well.
> "He's fine," Toohey said.
> About 70 other workers at the Tokaimura nuclear facility received
> doses from the accident. The highest dose in that group was about 10 rems,
> Toohey said doctors would not expect any near-term health effects from
> exposures, although it could increase their lifetime risk of developing
> There was some exposure to residents in the area, but the levels probably
> inconsequential from a health standpoint, Toohey said.
> Blood tests of 1,800 nearby residents in the first week after the accident
> not show any substantial change in blood counts, but Toohey said accident
> specialists recommended a second test after a month. The effects from low
> would most often be seen about 30 days after exposure, he said.
> "The lower the dose, the longer it takes to see the response," Toohey
> There was a bit of unusual proof that neutrons -- which will penetrate
> anything -- reached the residential neighborhoods around the nuclear
> A gold necklace in a house 200 meters away became radioactive because of a
> reaction in which a neutron was captured by the stable material, creating
> small amount of the radioisotope, Au-198.
> "It was very slightly radioactive but not a concern," Toohey said."