Sediment Quality in Puget Sound Year 2 - Center for Coastal ...

Precautions described above were taken to avoid contamination of the samples from engine
exhaust, atmospheric particulates, and rain. A double volume sample was collected at five
stations for duplicate chemical analyses. All samples were labeled and double-checked for
station, stratum, and sample codes; sampling date; sampling time; and type of analysis to be
performed.
Samples for chemical and toxicity tests were stored on deck in sealed containers placed in
insulated coolers filled with ice. These samples were off-loaded from the research vessel every
1-3 days, and transported to the walk-in refrigerator at Ecology HQ building in Olympia. They
were held there at 4OC until shipped on ice to either the NOAA contractors for toxicity tests or
the Manchester Environmental Laboratory for chemical analyses by overnight courier. Chain of
custody forms accon~panied all sample shipments. After a minimum of 24 hours following
collection and fixation, the benthic samples were rescreened (i.e., removed from formalin) and
exchanged into 70% ethanol.
Laboratory Analyses
Toxicity Testing
Multiple toxicity tests were performed on aliquots of each sample to provide a weight of
evidence. Tests were selected for which there were widely accepted protocols that would
represent the toxicological conditions within different phases (partitions) of the sediments. The
tests included those for amphipod survival in solid-phase (bulk) sediments, sea urchin
fertilization success in pore waters, and microbial bioluminescence activity and cytochrome P45C
HRGS induction in an organic solvent extract. Test endpoints, therefore, ranged from survival to
level of physiological activity.
Amphipod Survival - Solid Phase
The amphipod tests are the most widely and frequently used assays in sediment evaluations
performed in North America. They are performed with adult crustaceans exposed to relatively
unaltered bulk sediments. Ampelisca abdita has shown relatively little sensitivity to nuisance
factors such as grain size, ammonia, and organic carbon in previous surveys. In surveys
performed by the NS&T Program (Long et al., 1996), this test has provided wide ranges in
responses among samples, strong statistical associations with elevated toxicant levels, and small
within-sample variability.
Anzpelisca abdita is a euryhaline benthic amphipod that ranges from Newfoundland to south-
central Florida, and along the eastern Gulf of Mexico. Also, it is abundant in San Francisco Bay
along the Pacific coast. The amphipod test with A. abdita has been routinely used for sediment
toxicity tests in support of numerous EPA programs, including the Environmental Monitoring
and Assessment Program (EMAP) in the Virginian, Louisianian, Californian, and Carolinian
provinces (Schimmel et al., 1994).
Amphipod survival tests were conducted by Science Applications International Corporation
(SAIC), in Narragansett, R.I. All tests were initiated within 10 days of the date samples were
collected. Samples were shipped by overnight courier in one-gallon high-density polyethylene
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