Naidu et al., 1980). The relative difference in intake between the 1.5-y to 3-y age group and adults is nearly the same for both major diet surveys (Robisonet al., 1980; Naidu et al., 1980). Infant/Child (9 monthsto 1.4 y) Both breast-fed and bottle-fed infants, starting around 9 months, occasionally are given small amounts of soft crab, fish, breadfruit, papaya, and pumpkin (Marsh, 1973; Pollock, 1974; Hinshaw, 1988). Radionuclide Concentrations in Local Foodsat Rongelap Island The concentrations of radionuclides in foods at Rongelap Island at Rongelap Atoll are listed in Table A-1. The listed concentrations are from the Northern Marshall Islands Radiological Survey completed in 1978 and additional sampling done by LLNL in 1985 and 1986. These additional local foods would probably be no more than 20% of the adult intake. Infants (4 to 8 months) The diet of infants 4 to 8 monthsold in the Marshall Islands varies depending on a mother's preference and the mixture of locally grown and imported foods applicable to a specific atoll. In general, however, infants are usually breast-fed for the first 12 to 18 months, and sometimes for as long as 2 years (Marsh, 1973; Pollock, 1974; Flaherty, 1988; Hinshaw, 1988). Bottle-fed babies occasionally are given coconut fluid or milk if formula becomes scarce and breast-fed babies may also be given small quantities of coconut milk. In summary, the infant (4 to 8 months) diet in the Marshall Islands consists primarily of milk either by breast-feeding or bottle-feeding with occasional, small supplements of coconut Intake of 9°Sr and 137Cs from Ingestion of Local Foods Strontium-90 NewborrvFetus. Work conducted during the height of the atmospheric nuclear testing program, when 99Sr in milk was of concern, indicates that the ORMPensions = 0.5, where the ORis a term coined by Comar etal. (1956), and is defined as the ratio of the pCi 9°Sr per g of calcium in a target organ divided by the pCi 90Sr per g of calcium in a reference source. In other words, the discrimination against strontium compared to calcium across the placental barrier is about a factor of 2 (Bryant and Loutit, 1964; Comar et al., 1965; Kawamura et al., 1986; Tanaka et al., 1981). Furthermore, the OR“. = 0.25 (Bryant and Loutit, 1964; milk or coconut fluid. Comar et al., 1965). Consequently, the Infant (0 to 3 months) across the placental barrier, is 0.25 x 0.5 = 0.13 bo oy. Ce, ORSardin’ which includes the discrimination The diet of infants in the Marshall Islands varies depending on a mother's preference. Infants are either breast-fed, which is the most usual case, or they are bottle-fed with formula (Bryant and Loutit, 1964; Lenihan, 1967; Comar et al., 1965). The oR“ of 0.5 means that half as much 99Sr per g of calcium is present in the and evaporated milk (Marsh, 1973; Pollock, newborn/fetus as the adult, and the dose 1974; Flaherty, 1988; Hinshaw, 1988). received by the newborn/fetus will be a combination of this lesser 90Sr concentration and the difference in dosimetry for a fetus versus an adult. Infant (0 to 3 months). As was discussed in Our general observation is that the use of formula and evaporated milk for feeding infants has increased over the past few years. In either case, the total diet consists of one or the other overthe first 3 to 4 months. ~—69800lb3 the diet section, the major source of food for