858
BENINSON, RAMOS, AND TOUZET
The stillbirths’ entries are, of course, the total discrimination factors
between the mothers’ diets and the fetal bones. The agreement between
the two sets of estimates is fairly good. In spite of all uncertainties
involved, the values suggest that in young infants thereis little discrimination against strontium and that discrimination builds up reach-
ing the “agreed” adult value of 0.25 during the second yearoflife.
The importance of such small discrimination in young infants
should not be overestimated. [If bone turnover is rapid, the skeleton
burden of Sr would depend strongly on intakes at later ages, and the
0.25 value would be relevant in any long-term-risk evaluation. Turn-
over rates could likely be estimated from *Sr/stable-strontium
specific-activity
measurements,
but this would require more data
than those obtained in the study presented in this paper.
REFERENCES
1. D. Beninson, A. Migliori, and E. Ramos, Strontium-90 in the Diets and
Bones of Children. Progress Report 1962-1963, in Fallout Program Quar-
terly Summary Report, USAEC Report HASL-149, pp. 105-118, Health and
Safety Laboratory, January 1965.
2. D. Beninson, E, Ramos, and R. Touzet, Strontium-90 in the Diets and Bones
of Children. Progress Report 1964, in Fallout Program Quarterly Summary
Report, USAEC Report HASL-149, pp. 119-129, Health and Safety Laboratory, January 1965.
3. Health and Safety Laboratory, Manual of Standard Procedures, USAEC Report NYO-4700(Rev.), August 1962.
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Soc., B159: 449 (1964).
10. C&tedra de Pediatrfa, University of Buenos Aires, private communication.
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