15
hand, the estimated mullet gill concentrations are higher than levels
measured in the snapper.
The largest difference in concentrations are
associated with the viscera samples.
However,
if the estimated plutonium
in the intestinal contents of the mullet are subtracted from the measured
total viscera concentration, only 0.94 pCi/kg wet would be associated with
the mullet viscera.
This is roughly a factor of two higher than the
concentration associated with the snapper viscera.
The concentration of
plutonium associated with the contents in the snapper stomach was small.
Although the intestinal tract of the snapper is small relative to the
stomach,
the ingested material in the intestine tract does contribute some
weight to the viscera sample.
If we assume this weight to be half the
Sample weight, as was the estimated weight for the contents in the mullet
GI tract,
the concentration of
239+240
Pu associated only with the snapper
viscera would be equivalent to the concentration in the mullet viscera.
Concentrations of
2394240, in the eviscerated samples of mullet
and
snapper are essentially identical whereas the average concentration in the
whole mullet, on either a wet or dry weight basis,
than the concentration in the entire snapper.
is 4 to 5 times higher
We would agree with previous
studies that there is a difference in the concentration of plutonium as a
function of trophic level and feeding habits only when concentrations in
the entire fish are compared.
However,
eviscerated fish tissues are considered,
if only concentrations in the
the difference is insignificant.
Apparently mullet ingest more plutonium associated with their food
items than the snapper, but the amounts of
2394240
Pu concentrated in the
muscle, skin or bone in fish from either the first or second trophic level