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ADDENDUM
Since the original discussion above was written, further consideration bas been given to the work of Strandgvist and others* on the effect
of fractioneticn of doses delivered to the skin end the onset of the
observed results.
It will be recalled (page 10) thet X-ray doszs to the
compared to a one-treatment dose.
A log-log plot of total doses versus
days after initial treatment yields straight lines.
Basically, this means that as doses are being delivered to the skin
a certcin rete of repair is taking plece.
The over-all effect might be
that higher initiel deses from fallout material night be allowsd than if
one were to integrate the dose over a period of tine without corsiderstion for the rersir,
FEecause of the difference in shapes of tha total
beta dose curves for varying times of initial fallout versus Strandgvist
X-ray curves the difference between the two curves cannot be expressed
as a sinvle relationship.
Strandgvist quotes a 1000 roentgen dose in cne treatment to pro~
duce erythoma using X rays {a somewhat smaller mumber than other data
quoted ebove), 1250 roentgens if divided into two equal daily éoses,
1450 roontgens if divided into three equal daily doses, etc. O2 course,
there are differences between these X-ray doses and beta doses from
fallout material such as differences in doses at increasing depth of
tissue and the fact that the X rays were delivered essentially as an
instantaneous dose at intervals of a day while the beta dose rates are
8 HEREet om ra ng
assumed to follow the hee,
However, accepting the assumptions of
biological equivalence of these roentgen and beta doses and t7le2,
*Sievert, Rolf M.
"The Tolerance Dose and the Prevention of Injuries
Caused By Ionizing Radiations".
Y.XX, Na. 236, August 1947.
British Journal of Radiology,
Lf Pe Heamp +
2NT oe
pero o.hee
skin were fractionated in equal daily amounts, and the biological effects