in the skeleton, as was 33 percent of the 89sr. Pecher also noted the high
yield and ease of counting of 89Sr, compared to *5Ca. Pecher and Pecher
(1941) also demonstrated in mice the ability of radfostront tum to cross the
placenta and the manmary gland in mice and concentrate {n young bones.
[Erf
and Pecher (1940), as mentioned above, collected milk fran two cows injected
with 89Sr, and recovered 1] and 8% during the 4.5 days after injection.
Other studfes included investigations into the bflftary secretion of
calcium and strontium (Greenberg and Troescher, 1942), the fnfluence of growth
horsone on strontium deposition (Marx and Reinhardt, 1942), and the effect of
parathyroid extract on strontium metabolism (Tweedy, 1945).
Treadwell? et al. (1942) performed metabolic studfes of neoplasms of bone
using 89Sr, which was found to be taken up by growing bone and by osteogenic
tumor tissues.
Possible therapeutic use of radioactive strontium was
mentioned (Treadwel} et al., 1942) as a means of increasing radiation dose to
affected areas, that fis, as an adjunct to ongoing tnerapestic methodologies.
The assimilation of a number of fission products and heavy elements, and
their distribution and retention were studied in rats by Han{tton (1947).
For
89Sr and 90Sr, he found that 5 to 60% of an oral dose was absorbed, that
65% accumulated in bone, and that they were exponentially eliminated with e
half-time in the body of more than 200 days.
Copp et al. (1947) also investtgated the metabolism of radioactive strontiwe, along with yttrium, cerjum, and plutonium.
Of these, only strontium was
absorbed appreciably fran the gastrointesting) tract.
Absorption of stron-
tium, furthermore, was 25 times as great in growing rats fed o low calcium
Giet es fin adults with ample calcium In the diet.
A deficiency fn phosphorus
Caouted a 3-fold decrease in strontium retention beause of
tnpthifion of done