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as vitellogenin and a variety of steroid hormones. Macrophage aggregates, and a health
assessment index, were also included in the suite of analyses conducted. The systems
covered included the Mississippi, Columbia, Rio Grande, Yukon, and Colorado Rivers, as
well as an investigation of rivers in the Southeastern United States. River systems were
intensively sampled over a 1- to 2-year period, but individual sites were only sampled
once in that period, with the intention of returning to the same system several years later.
However, the BEST program ended in approximately 2006. Nonetheless, this biomarker-
focused approach, for the first time, gave a broad view of fish health in rivers of the United
States. One of the more notable findings from this effort was documentation of widespread
intersex in certain fish species from U.S. rivers. The most common form of intersex was
the presence of testicular oocytes, but the specific etiology of this condition remains to be
determined (Hinck et al. 2009). To look at temporal trends, fish tissue contaminant data
were compared to similar data collected 10-20 years earlier (Schmitt et al. 2005; Hinck et
al. 2006); however, there were no similar earlier measures of biomarkers, so trends in these
measures could not be assessed. Despite not being currently funded, the BEST program
provides a rich legacy of data, archived tissue samples, and methods that can be used in
the future to determine if there are, in fact, temporal trends in fish health in response to
chemical contaminant exposure. Most impressively, the methods used in BEST are well
documented and described (Schmitt and Dethloff 2000) and are available online (http://
www.cerc.usgs.gov/pubs/BEST/methods.pdf), and the data collected are likewise avail-
able online, in an easily searchable form (http://www.cerc.usgs.gov/data/best/search/).
15.3.4 Puget Sound Assessment and Monitoring Program
Washington State, in the northwestern corner of the contiguous United States, contains
within its boundaries a large estuary that is unique among U.S. estuaries, being that it is
a deep fjord, formed by glacial scouring, and home to a growing and urbanizing human
population. Beginning in the 1970s, Puget Sound has served as an “outdoor laboratory” to
study the effects of chemical contaminants on marine fish species, and many of the find-
ings from Puget Sound were used to design the NBSP component of the NS&T (Pierce et
al. 1978; Malins et al. 1985; Myers et al. 1987). In 1989, a state-funded monitoring program,
PSAMP, was founded, and part of its mission was to monitor for trends in fish health and
chemical contaminant exposure in Puget Sound.
Central to this trends investigation has been the continued histopathological examina-
tion of tissues of English sole (
Pleuronectes vetulus
), because it was in this species that the
strongest link between PAH exposure and liver disease, including neoplasia, had been
demonstrated. Results from PSAMP show convincingly that the prevalences of toxico-
pathic liver disease have declined sharply along the Seattle waterfront, starting in 1999,
through at least 2007, and that this trend is accompanied by reductions in PAH exposure
as measured by FACs in bile (Figure 15.1; State of the Sound 2009). This improvement in a
biomarker of fish health is very likely a reflection of the efforts to achieve source control
and clean up contaminated sediments in this area. An additional example of biomarkers
being used to demonstrate the success of management actions was recently reported in
Puget Sound as well. Eagle Harbor, one of the most severely contaminated sites in this
basin, was remediated by placing a cap of clean sediment over areas where total sedi-
ment PAHs exceeded 100,000 ppb on a dry weight basis. Before capping, almost 80% of
the English sole from this site had toxicopathic liver disease. After capping, however, liver
disease in this population of fish declined over the course of several years, and recently
was reported to be at levels consistent with other nonurban sites in Puget Sound (Myers et
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