DIETARY INTAKE OF RADIONUCLIDES
60
T
]
885
|
_
TEEN-AGE
50 ee
4
40
|
30
PERCENT
pee
ewe
20
10
RURAL
|
88 em MILITARY
OOO
O WEST
UNITED STATES
0
URBAN
-10
=
BALANCE SHEET
-30
1960
I
1961
{
1962
|
1963
YEAR
Fig. 6—Influence of using various consumption estimates on annual
Sy-intake levels for the western United States for 1960—1963.
With Sr as an example, the annual intake from fluid milk varied
from 400 to 4400 pc during 1963, or better than tenfold. The inade-
quacy of the use of one value as an estimate of “Sr intake from milk is
quite obvious. However, it is possible to subdivide the areas by
geographical features and reduce the range in values from tenfold to
fivefold or less. When the data were grouped in this manner, it was
clear that even further subdividing might be desirable (see Table 2).
The existence of such widespread values in a product such as milk for
which there is less variation annually, seasonally, and between various
social, economic, and ethnic groups than many other foods indicates
the need for more-precise estimating procedures. When the potential
variations in total-diet estimates are considered (Figs. 4 to 6) and
when these are coupled with variations of equal or greater magnitude
in nearly every food product or food category, then it becomes highly
questionable if our estimates of radionuclide intake are accurate for
many groups of the population.