Marine Ecosystems Analysis (Puget Sound) Project

Project Description
EXECUTIVE SUMMARY:

The Marine EcoSystems Analysis (MESA) Puget Sound Project has
undertaken intensive studies of Puget Sound, with particular
emphasis on such highly industrialized areas as Elliott and
Commencement Boys and Sinclair Inlet. These studies have
involved chemical, biological and oceanographic investigations
aimed at determining the concentrations, fates and effects of
toxic chemicals in the Puget Sound ecosystem. An integral part
of these studies has been toxicity tests with field-collected
sediments. The present study was initiated to extend sediment
toxicity testing to two previously untested industrialized Puget
Sound embayments: Bellingham Bay and Everett Harbor. Relatively
high concentrations of toxic chemicals had been reported from
these two areas (Malins et al., 1982). The contaminant mixtures
discovered there differed somewhat from those observed in other
parts of Puget Sound. This study was initiated to determine if
sediments from these two areas were toxic or not. Toxicity
testing was also conducted south of Bellingham Bay at Samish
Bay, chosen as a reference area. A total of 22 stations were
chosen for study: 10 in the Everett Harbor area, 10 in
Bellingham Bay, and 2 in Samish Bay. Composite sediment grab
samples were collected from each station and tested for acute
lethal, sublethal, partial life-cycle, cell reproduction and
genotoxic effects. These effects were examined utilizing
sensitive test methods applied elsewhere in Puget Sound (Chapman
et al., 1982a; in press a, b). An additional station south of
Everett Harbor was tested (with negative results) for acute
lethal and sublethal effects. On the basis of acute lethal,
sublethal, partial life-cycle, cell reproduction and genotoxic
effects testing, Everett Harbor, Bellingham and Samish Bays were
less toxic than contaminated areas such as the Duwamish Waterway
(Elliott Bay) and the Commencement Bay Waterways. Everett Harbor
sediments were more toxic overall than those from Bellingham
Bay. Samish Bay sediments only showed toxicity in cell
reproduction and genotoxic tests, suggesting very different
sediment chemistry in this area. Partial life-cycle bioassays
with oyster larvae (Crassostrea gigas) were conducted by
exposing fertilized eggs to settled sediment slurries for 48 h
then determining the number of live larvae and any
abnormalities. A total of 19 stations demonstrated significant
abnormalities or mortalities; the two reference stations showed
no significant effects. Acute lethal bioassays were conducted
with the sensitive amphipod Rhepoxynius abronius. Two stations
(one each in Bellingham Bay and Everett-Harbor) demonstrated
significant acute lethal effects; the two reference stations
showed no significant effects. Sublethal effects measurements
were conducted with the oligochaete Monopylephorus cuticulatus
by exposing the worms to sediment elutriates and measuring
respiration rates. Seven stations demonstrated significant
respiration rate differences compared to controls; the two
reference stations showed no significant effects. Cell
reproduction studies were conducted by exposing rainbow trout
gonad (RTG-2) and bluegill fry (BF-2) cells to sediment extracts
during logarithmic growth. Eight stations (including one
reference station) significantly reduced cell growth in RTG-2
cells, and three stations (including both reference stations)
significantly reduced cell growth in BF-2 cells. Genotoxic
tests for chromosomal damage were conducted by exposing RTG-2
cells to sediment extracts and determining mitotic (anaphase
aberration) effects. Sediment extracts from eight stations
(including one reference station) caused significant chromosomal
damage. Physical and chemical data for tested samples (particle
size, total volatile solids, digestible organic carbon, and
extractable organic matter) were within the ranges observed for
other areas of Puget Sound with the following exceptions. A high
clay content was noted in Bellingham Bay sediments and a high
percentage of total volatile solids was noted in inner Everett
Harbor sediments.

INTRODUCTION:

One of the intents of the MESA Puget Sound Project is to develop
an understanding of the effects of environmental contaminants upon
Puget Sound biota. High environmental levels of particular
chemicals have been detected in sediments from industrialized
embayments of Puget Sound, and a variety of in situ biological
effects (e.g. tissue abnormalities in fish and shellfish, changes in
biological community structure) occur in areas associated with high
levels of various contaminants (Malins et al., 1980, 1982; Dexter et
al., 1981; Long, 1982). Direct evidence of toxicity from Puget Sound
sediments has recently been provided for three of these industrialized
embayments: Elliott Bay, Commencement Bay and Sinclair Inlet
(Chapman et al., 1982a, in press a, b).
Contaminant mixtures found in sediments from Bellingham Bay and
Everett Harbor were known to differ from those of the previously
tested areas. However, the relative toxicity of sediments in these
two areas was unknown. Recent indirect evidence of the potential
for biological effects among biota captured in the two areas
has been collected.
Field studies have recently recorded fin rot and lesions in bottom
fish in Bellingham Bay and Everett Harbor (Campana, 1983;
Gronlund et al., 1983). The intent of the present study was to
determine whether marine sediments from these embayments also
exhibited toxic biological effects in direct exposure tests.
Accordingly, composited sediment grab samples were obtained from a
total of 22 stations (including a non-industrialized reference area,
Samish Bay). These samples were tested for possible biological
effects using a range of species and test methodologies. Sediment
collected from a station in Possession Sound, south of Everett
Harbor, was also tested on an opportunistic basis. The results were
used to determine the relative toxicity of Everett Harbor and
Bellingham Bay samples compared to those from other tested areas
of Puget Sound.