PoreNees, . yee wae 3 Feta te wate ys GG ae re oo eee of RESULTS AND DISCUSSION i a Daily Activity Ingestion Rates Daily activity ingestion rates were calculated for dosimetrically significant nuclides post return. a An exponential decline was proposed for the inges- tion rate within a population subgroup and initial reference values are given in aM Figures 10 through 14 (June 1, 1957, was assigned as a return date to Rongelap). Figure 10 demonstrates the differences in ingestion of 1370, for various popula137 tion subgroups. This undulating pattern was exhibited by Ce, 905, and Ory, nuclides for which sufficientdata existed for analysis. Differences in ingestion rates of the stable elemenc at: the same geographic location have been shown to occur among members of a population CICRP . 23). Age dependent diet studies for ingestion of Cs for urban’‘Japan have values varying from 1] yg d “I for adults to 8.6 ug d *for childreg, Srin a@ weste) type diet rose from 600 jg a7for infants to 690 ug 7 for 5 year olds to 3,600 yg a7 for 13 year olds and fell to a mean of 1,900 gtator adults. 2n in the United Kingdom rose from 2 to 40 mg av, the higher value of Zn being observed in adult tea drinkers. Fe ingestion in a western type diet has a mini- mum at age 3 and maxima at ages 1 and 20 years. Co is ingested at a rate of 20 ug a? for Japanese adults and half this amount for children. population also exhibits dietary changes as a function of age. The Marshallese The authors of che Marshall Islands Diet and Living Pattern Study (Ns80) observed coconut sap being used ss a major food supplement for infants, and later in adult life es 4 Major source of daily fluid intake. Since coconuts and coconut tree sap pro- vided the major source of 1370, on Bikini Atoll (Le80, Mi80), the shape of Fig: ure 10 was in agreement with the observed diet pattern. 22 -