ne oe meinRetiegee * . Figure 4 indicates that v'*h the use of this qiodel for biological Aalf-ti. , the highest and “Icwest doses ter all ages from a given intake of cesium-187 aiffer by a factor of about two. This occurs exen though body weights vary by a ~€ector.of tut 20, and bioicgical half-times wary by a fector of about 10. For the younger ages, those sess than 1 year of age receive the ‘ighest dosz. Those 70 to 80 years of age may teceive a comparable dose. However, definitive ar an oe se Again, if one assumes that the dietary item Table 2 also presents the average consumption ‘by each age group relative to consumption by maics less than 1 year of age (the intake wormalization factor). The average consumption for males less than one year of age is seen to be 17.8 ounces per day. This is approximately one-half liter per day (16.9 oz/day). Table 2. Average daily fresh whole milk consumption at home in U.S.* Average consumption Age {yeare) (Ruid ounces! — Wale TA... 9-4..-2222. 3-8... 20-14. ...-.. $5-19_.. 2... 20-24... 25-29_...... 90-34_...-. 85-44. ...... 45-54... 55-64 8. >85.. 17.8 17.8 16.6 16.9 16.3 11.8 9.8 8.7 38.3 7.6 8.1 8.6 : No con- Normalization factor consumption/ <I o sumption fyear male consumption (percen Female Male 16.3 16.9 14.5 12.7 10.2 7.8 6.8 8.7 8.7 8.4 5.9 6.8 38.0 15.9 20.5 25.0 28.9 35.1 39.2 87.5 30.1 42.0 40.9 25.4 1.0 1.0 08 05 .92 06 55 49 47 43 45 48 Female .82 . .38 82 82 3 33 38 i The doses in figure 4, averagedfor each age zroup, have been modified by the normalization factors in table 2 to illustrate the effects that st se i j 1 ABE Goon) Figure 5. Total whole body and bone marrow dose from internal cesium-137 versus age (an assumed pattern of dietary intake of cesium-187 in milk for males less than 1 year of age consuming 1 »Ci) The influence of the pattern of milk consumption in table 2 is to reduce the average doses for most ages relative to the doses in figure 4. The sex-related differences in milk consump- tion cause males to receive higher average _doses than females for all ages. The difference fn dose between ages receiving the highest and ; lowest values is a factor of about four for... male and about five for female, and males less than 1 year of age receive the highest dose. - The yearly dose that would be received by various age groups from a continuing daily intake of cesium-—137 may be estimated by determining the average cesium-137 body burden during the year and using the following: , 05 -8l 72 58 padeet Someat CaranBatetehaste Femae Bon te ey FeedCones December 1965 3 - wi interest is whole milk, the doses in figure 4 wan be modiiied by a pattern of intake for milk. “fable 2 presents data on average at-home milk consumption may be underestimated for those, ages consuming whole milk away from home. 0d lenea consumption may have on shown in figure 5. dita for ages greater than 50 are not available . and the model suggested may not be really representative for ages over 50 years. eensumption as a function of age. Values of -. verage consumption in table 2 were developed from a percentage distribution of milk intake by age (Radiological Health Data, January 31963). This study of at-home milk consumption v¥'as conducted throughout the United States in July 1962. Since the study did not include sonsumption of whole milk outside the home, npOMNEPR Ee ER me ny a pattern of m dose, The result. B/W + where: (5) Dee ‘85.7 D,=dose rate (rads per year) B=average body burden (nanocuries) and W=body weight (kilograms) The determination of average body burden for a continuing intake of cesium-137 is de- scribed in the following section (see equation (9) and figure 7). . 116