"3600 cGy [rad]- any child under 7 who receives this dose of radiation
to the whole brain and spine is guaranteed to be in special education classes.
-
"now normally 2380 cGy, supplemented with several rounds of chemotherapy-.
"-seven out of ten kids with medulloblastomas treated with 1800 cGy
during a pilot study in the late 1980s are alive today.- The new treatment
protocol calls for patients to receive a total of 1800 cGy over 6 weeks
to the head and spine, with a boosted dose to the tumor itself." [This
is "low dose"!]
Remember that a single CT averages 1 cGy [rad] and at high dose rate.
Thus a study of ALARA and LNT potential ill effect that compared 3 cGy/year with placebo (as I am exploring) would have at least a 100 x safety margin, although being about 10 x the usual background (including delta from potassium) and would be about 1/10 what some Ramisar residents now receive (@260mGy/year)..
Howard Long
RuthWeiner@AOL.COM wrote:
I heard an after-dinner talk Friday the subject of which I thougt might be of itnrest to RADSAFERs. The talk was by Tom Laughlin (sp?), who has published (with others) a LANL report on criticality accidents. He talked only about process accidents -- accidents that occur during chemical processing of fissile material. Some interesting points:There have been 22 such accidents since 1943, 21 of them in solution (liquid) media.
There have been 9 fatalities altogether (I think I remember this number correctly).
The accidents appear to be the result usually of
* not following specified procedures (taking short cuts)
* not being given proper procedures
*not understanding what the consequences of an accident would be.These accidents pose occupational hazards. There have been no health effects to anyone but workers, and no environmental effects.
Most interesting of all: in several accidents he discussed, workers stopping the criticality would get tens of rad or more in a very short time, with no apparent ill effect. At Tokaimura, the two heavily exposed persons died (one after 4 months and one after 6 months), but the third person, who received several HUNDRED rad, is apparently not only alive but in good health and leading a normal life.
Just thought this would be of interest. Tom is a dynamite speaker and I would suggest inviting him for one of your dinner meetings. If there is interest, I can get the correct spelling of his name and some contact information.
Ruth Weiner, Ph. D.
ruthweiner@aol.com