be the order of 10-15 days for i- to 2-year-old children and increases to
~ 100 days by age 20.
adult life.
It then remains reasonabiy constant throughcut
The body mass is less for the younger aze groups, and these
two factors tend to offset each other in dose calculaticns.
Doses to
Q
children are generally less than for adults as a result of the combination
fPsetting factors.
When the relative dietary intake is
Oo
of these two
.
ta
included, chiidren receive a lesser dose than acult
Therefore, dose
estimates for adults are usually a conservative estimate for children.
than 6 yr, including: adults.
or
vu
r
.
9O
:
.
.
:
c
pei 9 Sr/z Ca in human tone is greater Tor ages 1-5
rH
17 indicate that the
1p
o
_ 16
ct
90 Sr — Rerorts by Loutit, 15
>
>
es greater
However, the turnover rate is much more
rapid and the retenticn time much shorter for
Sr in azes 1-5.
The
combination of these two factors determines the bone burden, the annual
dose, and the dtse commitment resulting from a speciried ingestion of
9
9 Sr.
For children, these two factors tend to orfset each other; the
-
*
a
3
_
resulting ccse to children, therefore, fs not straightforward and is
4
Gerencent upon the reistive interaction of these two Tractors.
Any
+
UY
comparisen with adults must thererore take into account the age dependence
tp
of these Factors as well as the difference in dietary intake.
1
reported by Bennett”
is therefore used for estimating the doses to children.
ia
ao
,+
0
:
:
:
=
_s
.
7 Sr — Models developed ty ICRP for estimating
ct
ad
Dose Models and
Qs
4.
oO
:
90
+
.
;
18-2
ingested ~ Sr are considered to be ase invariant.
16.
_
-
;
.
bone dose from
A recent model from
.
;
Goes modei the child separately from the adult, and this model is
applied for estimating the bene
oses to children.
Q,
Bennett
The model.