from different islands and of pelagic species from the lagoon during the 8-ye
period.

Concentrations of 137¢s in the muscle tissue of all species of fist

during this period ranged from 7 to 460 pCi/kg wet weight.

The maximum

concentration of !3’cs in flesh, 460 pCi/kg wet weight, was measured in

surgeonfish collected from island B-1 in 1983, and the mean concentration i:
the flesh of all

weight.

reef fish during

the 8-year period

was 113 pCi/kg wet

The computed annual whole-body dose-equivalent rate to individuals

from !37Cs in the fish ingestion food pathway would have been less than 1 mr¢
(assuming a consumption

rate of 200 g of fish

flesh

per day and a

concentration of 113 pCi/kg wet weight).

Between 1977 and 1984, generally higher concentrations of !3’cs were

measured in muscle of reef fish from the northwest quadrant of the atoll (Bto B-5), and the lowest levels were found associated with reef species from
the eastern reef of the atoll.

In 1982, marine fish fillets purchased fron

stores in the Chicago area of the United States, contained 23+2 pCi/kg of

137¢s derived from global fallout.29

Table 7 shows that the mean |

concentrations of !37Cs in fish from islands B-10 to B-23 are now comparabl:
to the fallout levels in the store-purchased fish.

In Table 8 are shown several examples of the different concentration fc

137¢s (pCi/kg wet weight) measured in the muscle tissue of different reef
species collected from the same island during different years.

The mean

concentrations determined for all lagoon species during yearly intervals ar
shown in Table 7.

There does not appear to be any precise trend indicatinc

that the concentrations of !3/Cs in the muscle of these fish have been
changing over the years at some consistent rate.

There also appears to be r

clear trends of consistent differences in concentrations among the differen

reef species simultaneously sampled from the same location (see Appendix).
1978,

for

example,

at

island

B-1,

the highest

concentration among

different reef species was measured in mullet (Crenimugil).
1983 and at B-6 in 1980,

the

At Island B-1

the concentration in surgeonfish exceeded the

measured concentration in mullet and goatfish.

In

1984,

the measured

concentration of !3’c¢s in the muscle tissue of goatfish was larger than th:
concentration measured in any of the pelagic species collected off the islan

however, at B-6 and B-23 in 1978 and at B-6 in 1980, the concentration in
goatfish was lower than the levels detected in pelagic species from the
respective islands.

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