caggeennn
ee
STRONTIUM-90 IN MILE
approxiom 1954
1e Sr-90
through
: Health
ntration
ling the
n Sr-90
getables
also are
data suggest that plant foods prepared for human consumption do contain a
lower Sr-90 content than do plants consumed by animals.
From the incomplete data available, it is difficult to assess average values
for the levels of Sr-90 present in various foods consumed by humans, though
one can make some guesses on relative jevels. Kulp and Slakter (11) have
evaluated the Sr-90 intake of humans in the United States in late 1957, using
as a standard a level of 6 S.U. in milk, 10 S.U. in vegetables, and 15 8.U. in
cereals. They calculated an average Sr-90 intake of 6.5 8.U. for a person in the
United States. Using these values, and knowing the source of dietary calcium,
it is then possible to estimate the average Sr-90 intake of people in the various
countries of the world. Any such estimation suffers, since specific data on the
level of Sr-90 in the food in each country are not available and the effect of the
total calcium level in the diet has not been well-defined (18). However, such a
calculation does showthe effect a shift in eating habits could have on therelative
Sr-90 intake of a population.
‘e about
getables
ie levels
anerally
getables
on weil> forage
The various countries of the world, because of their differences in diet, receive
a different percentage of their dietary calcium from cereals, vegetables, milk,
and other minor products such as fish, meat, eggs, ete. The sources of calcium
in national diets for a few representative countries are tabulated in Table 4 (8).
average
‘ause of
oducing
n phosg about
ssing to
2 succu1 Data
yund in
3. The
TABLE 4
Sources of calcium in national diets (8)
Country
Sweden
United States
France
Italy
Peru
Portugal
Japan
]
verage
per day.
oe Sane
‘s}—
7
9
23
6
‘50
4
6
9
45
30
18
40 |
‘70
30
0.1*
Cereals
Vegetables
Meats, eggs, fish
——————_____—-—-(% total calcium intake)
4
6
4
4
5
7
8
12
D
19
14
5
17
37
5
26
35
9
46
25
il
Milk products
87
85
75
62
41
30
18
Twenty-one of the 35 countries listed by Eekelman et al. (8) receive more
than 70% of their dietary calcium from milk products. The countries selected
in Table 4 illustrate the large differences in the source of dietary calcium. If
the following Sr-90 levels are used, based on milk as 6 8.U., vegetables as 10 8.U.,
and cereals as 15 8.U., and the small contribution from other foods is ignored,
then the relative total amount of Sr-90 received in the diet, as well as the perTABLE 5
Estimated source of dietary Sr-90 for various countries
Country
United States
Italy
Portugal
Japan
From
cereals
From
vegetables
From
milk products
Sr-90 in total diet
9.7
35.8
42.4
65.9
(% total Sr-90 intake)
8.1
17.6
38.0
23.8
82.2
46.6
19.6
10.3
(Sunshine units}
6.2
8.0
9.2
10.5 (73)"
*On basis of 1956 rice crop (17).
[9 |