Vol. 53 - Alaska Resources Library and Information Services

clams from Bay 9 in the second post-spill sample was the only value which was
significantly different from the corresponding value in clams from the reference bay.
Concentrations of total other carbohydrates, which consist of trehalose and other nonglycogen
oligosaccharides and polysaccharides which yield glucose upon hydrolysis, were
highly variable and no obvious trends among samples from different bays or sampling
times were apparent.
Concentrations of total lipids in clams from Bays 7, 10 and 11
dropped
between the pre-spill and first post-spill samples and then returned to pre-spill or higher
values by the time of the second post-spill sampling.
In clams from Bay 9, total lipid
concentration increased between pre-spill and first post-spill and then dropped to the prespill
range by the time of the second post-spill sampling.
The degree of contamination of Mya truncata with petroleum hydrocarbons
varied greatly within each bay depending on the station at which clams were collected
(see Section 2.).
Data were available by station for petroleum hydrocarbon burden and
tissue glucose and glycogen concentration in Mya truncata from the second post-spill
collection (Table 4.2). Mean body burdens of petroleum hydrocarbons in clams from 30
stations in 4 bays ranged from 35 to 238 µg/g (ppm). However, there was no relationship
between body burden of petroleum hydrocarbons and concentrations of glucose and
glycogen in the tissues of clams. In Bays 9 and 10, clams were collected at both the 3-
meter and 7-meter isobaths. There were no statistically significant differences between
clams from the two depths in concentration in the tissues of petroleum, glucose, or
glycogen.
Fourteen different free amino acids were identified and quantified in the
adductor muscles of Mya truncata from the four bays. The mean concentration of total
free amino acids ranged from 12.45 to 23.25 µM/mg wet weight in clams from different
bays at different sampling times (Tables 4.3, 4.4, and 4.5). In clams from the two bays
receiving dispersed oil (Bays 9 and 10), the mean concentration of tissue total free amino
acids dropped between the pre-spill and first post-spill samples and then rose again in the
second post-spill samples.
The opposite trend was observed in clams from the bay
receiving oil alone (Bay 11), while tissue total free amino acid concentrations in clams
from the reference bay (Bay 7) remained relatively constant (range 15.37-17.65 µM/mg).
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