dusty surfaces would be secondary pathways. During the midday meal at Rongelap
Island, BRAVO dust probably fell directly onto plates and on the surfaces of
fish which were drying in the open. The area of one plate exposed to BRAVO fallout plus the area of a small fish is approximately 0.04 m2. If a 30-minute
lunch interval beginning at 5 hours post-detonation was assumed to be the plate
and fish exposure interval to dust, then about 40 mg would fall on this eating
area at Rongelap Island. During the preparation of the evening meal, about 0.1

m*

of surface area was assumed as the family food preparation area exposed to

dust during fallout deposition. On the average, each family was estimated to
consist of about 4.5 people (Sh57). Therefore an additional 100 mg of BRAVO de-

bris per family member was estimated to be consumed with the evening meal at 12
hours post-detonation.

As indicated by our reassessment of the urine result, a 3.4 x 106
Bq (93 Ci) intake of 1311 was estimated on the basis of measured 131; in urine
on day 17.. This was assumed to be a total per adult ingestion intake of about

1.1 x 106 Bq (30 wCi) at 5.5 hours post-detonation and 2.2 x 10® Bq (60 uCi) at

12 hours post~detonation. Therefore, intake with midday and evening meals
provided us with a reasonable pathway in terms of the mass of fallout ingested

since 140 mg corresponded to 3.3 x 106 Bq (90 uci) of 13!r,

In Table 17 we have presented the estimated activity intake (with
meals) of selected nuclides at Rongé lap Island. An adult male was assumed to
take in 3.4 x 106 Bq (93 WCi) of 13lt in order to normalize with urine data.
Other nuclides were estimated by normalizing the l3ly intake to Bikini ash composition which,

in turn, was normalized to exposure-rate measurements.

Activity

intake with meals was modified to agree with meal intakes appropriate for body
weight for the different age members of the exposed populations. This modification was based on an exponential relationship between total element intake and
body weight which we derived from data tabulated in the ICRP Publication 23, Ref-

erence Man (ICRP74).

Activity would have been ingested directly with meals at Utirik Island during breakfast, lunch, and dinner on March 2, 1954, due to fallout on
plates, on food preparation areas, and on the food itself. As mentioned
previously, Sharp reported that fallout particles were not visible to the eye at
Ucirik Island (0C68). Fallout activity was measured in cisterns even though cisterns were reported as covered, which indicated to us that BRAVO dust may have
contaminated the surface of covered food. Essentially, our estimates indicate
that the majority of the BRAVO activity fell during the time breakfast was
prepared and eaten. Assuming the same food eating and preparation areas as at
Rongelap, and the same family size, then about 30 mg of BRAVO dust was ingested
with the breakfast meal at 24 hours post-detonation.
Resuspension followed by redeposition was considered secondary to
direct deposition prior to and during breakfast. Our estimates of particle deposition velocity and reports of resuspension factors (ICRP8Q) indicate that the
entire fallout would have to be resuspended into the air many times over in
order to make resuspension an important pathway for internal thyroid dose. Dust
falling from the cloud and ingested with lunch and evening meals at Utirik was

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