PTI
ENVIRONMENTAL SERVICES
Policy Implications
of Effects-Based
Marine Sediment Criteria
Prepared for:
U.S. Environmental Protection Agency
Office of Policy Analysis
Washington, DC
Final Report
U.S. EPA Contract No. 68-01-7002
September 30, 1987

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PTI Environmental Services
13231 SE 36th Street, Suite 200
Bellevue, Washington 98006
/policy implications of effects-based
MARINE SEDIMENT CRITERIA
For
American Management Systems, Inc.
Arlington, VA
and
U.S. Environmental Protection Agency
Office of Policy Analysis
Washington, DC
'200
Property Of U S Environmental
'rotection Agency Library MD-1Q8
NOV i 3 1991

Final Report
EPA Contract No. 68-01-7002
September 30, 1987

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EXECUTIVE SUMMARY
The integration of sediment criteria into environmental decision-making processes
requires consideration of a wide range of policy issues. These issues derive from the
differing emphases of regulatory programs as well as technical considerations. In the
following report, the predicted extent and severity of potential problems posed ,by toxic
marine sediments is demonstrated by applying Apparent Effects Threshold (AET) values
to chemical monitoring data collected by the NOAA Status and Trends Program. The
AET is the chemical concentration in sediments above which statistically significant
biological effects are always expected for one or more effects indicator (e.g., bioassay
responses, alterations of benthic macroinvertebrate communities). AET values, derived
empirically from chemical and biological effects data, have been previously
demonstrated to be accurate predictors of adverse effects in multiple embayments in
Puget Sound of Washington State. In the present study, Puget Sound AET are used to
evaluate chemical data from the east, west, and gulf coasts of the U.S.
Overall, the AET approach was useful in distinguishing NOAA Status and Trends
stations and areas by degree of predicted biological effects. The relatively
contaminated embayments of the Northeast Region were identified as the most impacted
areas in the U.S. By contrast, most embayments in the Gulf Region were not predicted
to exhibit biological effects. Predicted biological effects in the Northwest/Alaska,
Southwest, and Southeast Regions were intermediate in magnitude between the effects
predicted for the Northeast and Gulf Regions. Thus, the AET approach was sufficiently
sensitive to discriminate among areas subjected to different degrees of chemical
contamination. Confirmation of the predicted effects would require biological testing
because no site-specific biological effects data were collected at sediment stations in
the Status and Trends program. However, the resolution obtained in this study is
important because it suggests that an effects-based approach can be used at areas
removed from heavily contaminated areas (e.g., marine Superfund sites) to rank
potential problem areas. This ranking effectively weights chemical concentration data
according to potential biological effects, an important consideration when comparing
sites of differing chemical composition.
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AET are based on highly site-specific biological indicators, including sediment
toxicity and in situ abundances of benthic infauna. Comparisons of fish pathology
results (a less site-specific indicator) from the Status and Trends program were made
with the AET predictions of sediment toxicity and benthic effects. The comparisons
showed that when the AET approach predicted widespread biological effects, signifi-
cantly elevated prevalences of kidney lesions were found in all cases. Prevalences of
liver lesions were elevated much less frequently than prevalences of kidney lesions and
showed no close relation with results of the AET analysis (similar to preliminary
results for liver lesions and AET predictions in Puget Sound).
Evaluations of additional data sets from southern California and San Francisco
Bay generally supported the conclusions reached from the analysis of the Status and
Trends data set. That is, the AET approach discriminated among stations subjected to
different degrees of chemical contamination. These latter data sets also contained
site-specific biological effects information. Based on site-specific sediment chemistry
results, the AET approach predicted impacted stations around sewage outfalls in
southern California that were similarly defined as impacted by an independent
assessment of benthic communities. Evaluations of the biological effects measured in
both the southern California and San Francisco studies showed that one or more
adverse effects were found at 14 of 15 stations (93 percent) where effects were
predicted to occur by the AET analysis. Policy evaluations based on the results of
these analyses focus on the following topics:
~	Use of effects-based criteria as a tool in managing coastal regions
where both nonpoint and point sources may have contributed to
toxic buildup in sediments
~	Application of effects-based criteria at potential marine Superfund
sites
~	Apparent usefulness of effects-based criteria in addressing
remedial action policy issues related to "how clean is clean."
Effects-based approaches such as the AET appear to have wide applicability for
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problem identification at marine sites that could be considered for listing on the
National Priorities List, and for monitoring changes in less contaminated coastal
regions of the U.S. The NOAA Status and Trends Program focused on monitoring
stations that were removed from direct sources of contamination, and several of the
stations could be considered appropriate "reference" stations for marine sediments.
Because AET distinguished relatively contaminated and uncontaminated areas sampled by
NOAA, such an effects-based approach may provide a technical basis for cleanup
criteria at remedial action sites. Confirmation of the applicability of AET (derived for
the Puget Sound region) by selective field testing in other parts of the country is
recommended.
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TABLE OF CONTENTS
EXECUTIVE SUMMARY	ii
LIST OF FIGURES	vii
LIST OF TABLES	viii
INTRODUCTION	I
BACKGROUND	1
OBJECTIVE	2
METHODS	4
APPARENT EFFECTS THRESHOLD APPROACH	4
DATA SOURCES	5
Evaluation of NOAA Status and Trends Biological Indicator Data	6
Evaluation of Biological Indicator Data from Other Studies	8
DATABASE SETUP AND RETRIEVAL	10
DATA ANALYSIS	13
DISTRIBUTION OF PREDICTED EFFECTS	14
COMPARISON OF PREDICTED EFFECTS AND OBSERVED EFFECTS	25
NOAA Status and Trends Data Set	36
Southern California Data Set	38
San Francisco Bav Data Set	43
EVALUATION OF POLICY IMPLICATIONS	45
MANAGEMENT OF COASTAL SEDIMENTS	49
IDENTIFICATION AND MONITORING OF POTENTIAL MARINE
SUPERFUND SITES	52
REMEDIAL CLEANUP ISSUES	54
RECOMMENDATIONS FOR FIELD STUDIES	55
REFERENCES	57
APPENDIX A - SUMMARY OF APPARENT EFFECTS THRESHOLD
APPROACH	A-l
APPENDIX B - SUMMARY OF FISH PATHOLOGY EVALUATIONS	B-l
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LIST OF FIGURES
Number	Page
1.	Locations of stations sampled in southern California along the 60 meter
depth contour (Source: Word and Mearns 1979)	9
2.	Locations of stations sampled in San Francisco Bay (Source: Chapman et al.
1986, 1987)	11
3.	Summary of stations with predicted biological effects by region	15
4.	Summary of which kinds of AET were exceeded at NOAA Status and Trends
stations	16
5.	Summary of the number of AET exceeded and the maximum factor of
exceedance	22
6.	Summary of AET exceedance by chemical group	26
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LIST OF TABLES
Number	Page
1.	Summary of fish pathology observations made during 1984 by NOAA's Status
and Trends program	7
2.	Summary of chemicals that exceeded their AET at NOAA National Status and
Trends stations	20
3.	Maximum factor at which different AET were exceeded by a chemical in each
major chemical group	31
4.	Summary of fish pathology at locations where one or more chemicals
exceeded an AET	37
5.	Spore densities of Clostridium perfrineens in relation to AET exceedance	39
6.	Summary of chemical contamination and biological effects in southern
California	40
7.	Summary of chemical contamination and biological effects in San Francisco
Bay	44
8.	Examples of major environmental legislation relevant to sediment criteria
policy issues	46
9.	Examples of potential applications of sediment criteria in implementing key
environmental legislation	48
Vll

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INTRODUCTION
This evaluation was conducted as a preliminary study for the U.S. Environ-
mental Protection Agency (EPA) Office of Policy Analysis (OPA) on implications
of applying effects-based sediment criteria to coastal regions of the United
States.
BACKGROUND
Toxic metals and certain persistent organic compounds (e.g., PCBs) tend to
accumulate in sediments. These chemicals can be transferred to the overlying
water or organisms through various processes (e.g., methylation, bioconcentra-
tion, resuspension, and other physical disturbances including burrowing), causing
threats to aquatic organisms and humans consuming contaminated organisms.
Because of these factors, the ecology work group of the Comparative Risk
Project in OPA has identified aquatic in-place pollutants as a significant
problem of unknown dimensions and severity.
The assessment of risks created by toxic chemicals in marine sediments has
been approached by environmental scientists in two general ways. One
approach emphasizes theoretical models to predict the partitioning of sediment
contaminants to interstitial water (a major exposure pathway for organisms
associated with sediments). The predicted interstitial water concentrations are
then compared to criteria based on laboratory measurements of biological
effects. The second general approach has sought to relate empirically the
results of laboratory sediment bioassays and in situ biological effects observed
in organisms associated with marine sediments to chemical concentrations
measured in the sediments. This latter, effects-based approach, is the basis of
this report.
The effects-based approach used in this project is the Apparent Effects
Threshold (AET) method, an existing tool for deriving sediment criteria. The
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AET is the chemical concentration in sediments above which statistically
significant biological effects are always expected for one or more biological
effects indicator (see METHODS section). AET were originally developed to
identify problem sediments in the Commencement Bay Nearshore/Tideflats
Remedial Investigation (Barrick et al. 1985). AET have been subsequently
expanded and their accuracy tested using biological and chemical data for all of
Puget Sound under sponsorship of EPA Region X, Washington Department of
Ecology, Washington Department of Natural Resources, and U.S. Army Corps of
Engineers Seattle District (Beller et al. 1986).
OBJECTIVE
The objective of this work is to apply AET to predict biological effects
from sediment chemistry data compiled by the NOAA Status and Trends Program
(NOAA 1987). The NOAA results include data for sediments collected along the
west, east, and gulf coasts of the United States (data for the Great Lakes were
excluded). The predicted extent and severity of potential problems posed by
toxic sediments will thus be demonstrated by an empirical approach to sediment
criteria. The Status and Trends stations were sampled by NOAA to indicate
changes over time along the U.S. coast, and are not necessarily representative
of the range of contaminant conditions in each geographic area. In particular,
the intent of the NOAA Status and Trends program is to monitor sediment
stations that are removed from the direct influence of point discharges. Areas
suspected of being heavily contaminated were generally avoided. Additional data
from selected regional programs (i.e., San Francisco Bay, and southern Califor-
nia in the vicinity of the major municipal outfalls) have been included as avail-
able. However, none of the Puget Sound stations originally used to develop the
AET are included, and the stations sampled by NOAA are outside of the heavily
contaminated nearshore areas of Puget Sound.
The empirical relationships used to establish AET do not prove a cause-
effect relationship between contaminants and effects. The focus of this
approach is to identify concentrations of contaminants that are associated
exclusively with sediments having statistically significant biological effects
(relative to appropriate reference sediments). The applicability of AET in
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predicting biological effects has not been tested outside of Puget Sound,
although a limited comparison has been conducted using biological effects data
in San Francisco Bay (Chapman et al. 1986, 1987). Hence, additional chemical
and biological testing would be required to confirm predictions of adverse
effects summarized in this report. The purpose of this report is to evaluate
implications of using effects-based sediment criteria on a national basis, not to
identify specific areas for potential remedial action.
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METHODS
APPARENT EFFECTS THRESHOLD APPROACH
In the AET approach, chemical data are classified according to the absence
or presence of associated biological effects for a variety of indicators to
determine concentrations of contaminants above which statistically significant
biological effects would always be expected to occur. The AET method and
accuracy tests in Puget Sound are summarized in a report prepared for the
Puget Sound Dredged Disposal Analysis study (PSDDA) and Puget Sound Estuary
Program (PSEP) (Beller et al. 1986). AET have been established for 64 organic
and inorganic toxic chemicals using matched chemical and biological data for
several biological indicators and embayments in Puget Sound. Because of patchy
biological and chemical conditions in the environment, it was important that
chemical analyses be performed on the same or nearly the same sediment that
was used in bioassays and benthic infaunal analyses. AET were available for
predicting significant effects based on the following biological indicators:
~	Depressions in abundances of major taxonomic groups of
benthic infauna (i.e., Crustacea, Mollusca, Polychaeta, and
total abundance)
o Amphipod mortality bioassay using Rhepoxvnius abronius
~	Oyster larvae abnormality bioassay using Crassostrea eiaas
~	Microtox bioluminescence bioassay using Photobacterium
phosphoreum.
For each chemical, a separate AET was developed for each biological indicator,
resulting in four sets of AET. A list of the different AET used for predictions
in this study is provided in Table A-l (Appendix A). Derivation of AET are
described in more detail in Appendix A. The AET method has been shown to be
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sensitive in correctly predicting impacted stations in Puget Sound, but in doing
so the approach can also predict impacts at stations that do not evidence
adverse effects (i.e., the approach is not completely efficient in only identifying
impacted stations). Therefore, predictions in other regions that are based on
AET should be verified.
DATA SOURCES
Chemical data from the NOAA Status and Trends Program (NOAA 1987), a
separate NOAA Status and Trends study in San Francisco Bay (Chapman et al.
1986, 1987), and the Southern California Coastal Water Research Project
(SCCWRP; Word and Mearns 1979) were compiled and compared with AET.
Chemical data were available for sediment samples from 126 NOAA stations
sampled in 1984. Forty-five coastal embayments are represented by this data
set. The San Francisco Bay study by NOAA contained chemical data for nine
samples collected in 1985. Chemical data from the SCCWRP study included 71
sediment samples collected in 1977 along the 60-m depth contour.
Data were also compiled for ancillary sediment variables (e.g., total organic
carbon, sediment grain size) and other tracer variables as available (e.g.,
numbers of Clostridium perfringens spores). Data were transferred to a DBase
III database, verified, and cross-referenced with station identifier information.
The verified chemical concentration data were compared with AET values
developed from the database of chemical and biological effects results for Puget
Sound.
Biological effects data analogous to those used to generate Puget Sound
AET were available for only some of the chemistry stations. In the NOAA
Status and Trends Program, biological data were available on the prevalence of
fish histopathology disorders and concentration of chemicals in mussel tissue.
Mussel tissue data have not yet been evaluated. Fish histopathology data are
not directly comparable to the highly site-specific bioassay and benthic infauna
data supporting the Puget Sound AET. Thus, validation of the predictive
accuracy of AET for this study was limited to the select data sets from
California. In the SCCWRP study in southern California, benthic infaunal data
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were available for all stations. In the San Francisco Bay study, bioassay and
benthic infauna data were available for all stations. A description of the
evaluations of these biological data is provided in the following sections.
Evaluation of NOAA Status and Trends Biological Indicator Data
The only biological effect of chemical contamination evaluated by the
NOAA Status and Trends Program was fish pathology. Specifically, microscopic
abnormalities of the kidney and liver were evaluated in selected species of
bottom-dwelling fishes captured near the stations sampled for sediment chemical
contamination (Table 1). Data on spores of the bacterium Clostridium perfrin-
gens were also collected by NOAA, not as a biological effect but as a potential
indicator of contamination by domestic sewage.
For the present study, prevalences of the lesions identified by the Status
and Trends Program were compared with a prevalence of 0 percent using the
G-test and Williams' correction factor. Prevalences found to be significantly
different (P<0.05) than 0 percent were considered indicative of potential adverse
conditions. Because appropriate "background" conditions have not been defined
for the NOAA Status and Trends data set it is uncertain what level of fish
pathology in U.S. coastal waters can be considered "normal."
Sediment bioassays and measurements of in situ benthic infauna would
provide the best comparison for AET predictions of biological effects at the
NOAA stations but these data are not available. Use of fish pathology as an
indicator of sediment chemical contamination requires several caveats. First,
fish in general are not the best indicators of highly site-specific sediment
contamination, because many species migrate to some extent. Second, because
different fish species and age groups may exhibit different sensitivities to
sediment contamination, pathology data based on different species or age groups
throughout the U.S. may be influenced partly by interspecific or age-related
differences in sensitivity. Finally, although strong circumstantial evidence
suggests that many liver lesions and, to a lesser extent, kidney lesions, are the
result of exposure to toxic chemicals, conclusive cause/effect relationships have
yet to be documented in a field setting.
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TABLE 1. SUMMARY OF FISH PATHOLOGY OBSERVATIONS MADE DURING 1984
BY NOAA'S NATIONAL STATUS AND TRENDS PROGRAM



Number
Observed Lesions
Regi on
Species
of Sites
K i dney
L i ver
Northeast U.S.
Winter flounder
(PseudODleuronectes americanus)
8
MMCa proliferation
Hepatic neoplasia
Proliferative biliary hyperplasia
Southeast U.S./
Gulf Coast
Atlantic croaker
(MicroDoqodon undulatus)
11
MMC proliferation
Inflammatory necrotozing granulomas
Degenerative hyalin lesions
Cholangiocellular necrosis
Hepatocellular necrosis

Spot
(Leiostomus xanthurus)
14
MMC proliferation
Inflammatory necrotizing granulomas
Degenerative hyalin lesions
Cholangiocellular necrosis
Hepatocellular necrosis
Northwest U.S./
Alaska
English sole
(Paroohrvs vetulus)
3
Degenerat ion/necrosis
Proliferative disorders
Foci of cellular alteration
Degenerat i on/nec rosi s

Flathead sole
(HiDDoalossoides elassodon)
4
Degenerat ion/necrosi s
Proliferative disorders
Foci of cellular alteration
Degeneration/necrosis

Starry flounder
(Platichthvs stellatus)
6
Degenerat ion/necros i s
Proliferative disorders
Foci of cellular alteration
Degeneration/necrosis
Southern
CaIifornia
White croaker
(Genvonemus lineatus)
7
Degenerat i on/necros i s
Proliferative disorders
Degenerat i on/necros i s
Proliferative disorders

Hornyhead turbot
(Pleuronicthys verticalis)
5
Degeneration/necrosis
Proliferative disorders
Foci of cellular alteration
Degenerat i on/necros i s
8 MMC = Melanin Macrophage Centers

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Evaluation of Biological Indicator Data from Other Studies
Southern California—
Between 28 April and 9 August 1977, SCCWRP conducted a survey of
sediment contamination and biological effects at 71 stations distributed along
the 60-m isobath from Point Conception to the U.S./Mexico border (Figure 1;
Word and Mearns 1979). The survey encompassed a range of sediment contami-
nation, from reference conditions to the highly impacted conditions near the
major municipal sewage outfalls of Los Angeles and San Diego.
Benthic infaunal assemblages were used by SCCWRP as the primary
indicators of the biological effects of sediment chemical contamination. The
chemicals measured at each station included metals, total polychlorinated
biphenyls (PCBs), and total DDT.
For the present study, two kinds of benthic effects were evaluated in
relation to sediment contamination. The first kind of effect was a reduction in
the Infaunal Index below a value of 69. The Infaunal Index is an index of
benthic alterations based on changes in the functional feeding groups of benthic
taxa. The Infaunal Index can range from 0 to 100. Values lower than 69 are
considered indicative of altered benthic communities (Word and Mearns 1979).
The second kind of benthic effect considered in the present study was a
reduction in the abundance of echinoderms below a value of 9 individuals/m2.
Echinoderms have been found to be very sensitive to environmental perturba-
tions on the southern California Shelf. Abundances of echinoderms below a
value of 9 individuals/m2 are below the range of reference values defined for
southern California (Word and Mearns 1979), and can be considered to be
indicative of degraded conditions.
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13
14*
16-26
27-37
49
52
GB
81 •
62-69
Figure 1. Locations of stations sampled in southern California
along the 60 m depth contour (Source: Word and Mearns 1979)
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San Francisco Bay--
In 1985, Chapman et al. (1986, 1987) conducted a survey of sediment
contamination and biological effects at nine stations from San Francisco Bay
(Figure 2). Three of these stations were distributed at each of three locations,
representing a range of sediment contamination. A site in San Pablo Bay was
used as a reference area. Contaminated areas were sampled near Oakland in
the vicinity of industrial and maritime facilities and in the Islais Waterway, an
industrial waterway that receives storm/sewer overflows.
Laboratory sediment bioassays and benthic infaunal assemblages were used
by Chapman et al. (1986, 1987) as the primary indicators of the biological
effects of sediment chemical contamination. The primary chemicals measured at
each station included metals, high and low molecular weight polycyclic aromatic
hydrocarbons (HPAH, LPAH), pesticides, and total sums of PCBs.
For the present study, benthic infauna and two kinds of bioassays were
evaluated in relation to sediment contamination. The bioassays included the
amphipod (Rhepoxvnius abronius) mortality test and the mussel (Mvtilus edulis^
larvae abnormality test. These tests are similar to the ones used originally to
determine Puget Sound AET values. Impacts, as determined by Chapman et al.
(1986, 1987), included statistically significant differences (P<0.05) from the
responses observed using control sediments. Impacts to benthic invertebrates
were also determined qualitatively by Chapman et al. (1986, 1987), and were
based on cluster analysis and evaluations of the relative abundances of major
taxa and community characteristics such as taxa richness and numerical
dominance.
DATABASE SETUP AND RETRIEVAL
A DBase III database system was used to analyze data for this project.
The principal functions of the database are to:
o Store sediment chemistry data and related information, including
sample, station, and geographic basin identifiers.
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38* IS"
38* 15"
Son Paeia Bar (SP) Jairipu Jit#
Oakland (OA) Somplt Sin
Son Poble Bey
wo
38*00"
SAN RAFAEL
RICHMOND
liials Waitrwor US) Sanp4> Slfo
OAKLANO
Son froneiseo Boy
Figure 2. Locations of stations sampled in San Francisco Bay
(Source: Chapman et al. 1986, 1987)
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~	Store the various kinds of Puget Sound AET generated for
different biological effects indicators.
~	Compare AET values to survey data, using AET and chemical
data chosen by the user.
o Retrieve and display sediment chemistry measurements from
stations and dates selected by the user.
Because the 1984 NOAA Status and Trends data, as received, did not
include brief station identifiers, all identifiers used in the system were artifi-
cially generated. These identifiers were based on the geographic basin code
(also synthesized), with a unique digit appended to distinguish stations. None
of the chemical data were subjected to an independent quality assurance review
specifically for this study.
When performing comparisons to AET values, each chemical at each station
must be represented by a single number. Therefore any laboratory replicates or
field replicates were averaged. Laboratory replicates were averaged first, so
that field samples with different numbers of laboratory replicates were given
equal weight. Any field replicates at a particular station were weighted equally.
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DATA ANALYSIS
The following analyses were performed using chemical concentration data
in sediments from coastal areas of the United States:
~	Identification of stations exceeding specified AET values for
four kinds of biological indicators
~	Analyses of trends among stations, geographic regions, and
predicted biological effects for stations that exceeded AET
~	Interpretation of anomalous results and an assessment of which
AET for a range of biological indicators appear to be most
sensitive and least sensitive in identifying problem sediments.
Predictions of adverse biological effects were based on available chemical
data and Puget Sound AET. These data included 9 metals and metalloids and 18
neutral organic compounds (i.e., PAH, PCBs, and miscellaneous chlorinated
compounds). No sediment data were available for acid- or base- extractable
organic compounds (e.g., phenol, N-nitrosodiphenylamine) because only neutral
organic compounds were analyzed in the NOAA and SCCWRP studies. Data for
chromium, nickel, selenium, and thallium (all EPA priority pollutants) were not
included in the prediction of biological effects. These metals are predominantly
naturally-occurring in Puget Sound. Preliminary AET have been established for
chromium and nickel, but these AET will likely be modified after recommended
chemical and biological data from a broader range of samples has been incor-
porated in the Puget Sound database.
In the following sections, results are summarized for comparisons of
chemical concentrations to AET. The geographic distribution of predicted
adverse effects is presented, followed by a comparison of predicted effects with
available biological data. The most extensive biological data sets (outside Puget
Sound) were collected in NOAA and SCCWRP studies conducted in California.
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DISTRIBUTION OF PREDICTED EFFECTS
The broadest perspective of the national data set was achieved by grouping
results on a regional scale (Figure 3). From this perspective, the highest level
of chemical contamination and predicted biological effects was encountered in
the Northeast Region. At least one chemical exceeded at least one of four
kinds of AET (see Appendix Table A-l) at over 70 percent of the stations in
that area. Five or more chemicals exceeded their AET at over 33 percent of
the stations in the Northeast Region. Throughout the remainder of the U.S.,
five or more chemicals exceeded their AET only at stations in the Southwest
Region and, in that instance, only at 1 of the 32 stations sampled (3 percent).
Results of the regional analysis suggest that the lowest level of chemical
contamination and predicted biological effects was encountered in the Gulf
Region. Single chemicals exceeded their respective AET at less than 25 percent
of the stations in that area, and no more than four chemicals exceeded their
AET at any one station. The results for the Northwest/Alaska, Southwest, and
Southeast Regions were similar to one another and intermediate in magnitude to
the levels observed in the Northeast and Gulf Regions.
An evaluation of which kinds of AET (i.e., Microtox AET, benthic AET,
oyster larvae bioassay AET, or amphipod bioassay AET) were exceeded at each
station sampled during the NO A A Status and Trends program is presented in
Figure 4. The highest percentage of stations at which all four kinds of AET
were exceeded was in the Northeast Region (i.e., 63 percent). By contrast, the
corresponding percentages in the remaining regions ranged from 0 to 13
percent. Hence, the Northeast Region is distinguished as having the highest
percentage of stations at which at least one AET is exceeded (Figure 3), the
highest percentage of stations at which multiple chemicals exceed AET (Figure
3), and the highest percentage of stations at which all four AET are exceeded
(Figure 4).
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NORTHWEST REGION
INCLUDING ALASKA
NORTHEAST REGION
Pacific
UNITED STATES
Atlantic
SOUTHEAST REGION
SOUTHWEST REGION
Gulf of Mexico
GULF REGION
NUMBER OF CHEMICALS
EXCEEDING THEIR AET
PERCENT OF
TOTAL STATION
Figure 3. Summary of stations with predicted biological
effects by region

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NOAA Status and Trends stations
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BUOTT BAY
OCAACNCEMiNT BAY
NBCUALLY REACH
«©©

©0©
tflBCR
®0©	
0 100 200 300
0 100 200 300 400 500
©©©
CANADA
CCUJ^BAnVER
WASHINGTON
Pacific
COOS BAY
Ocean
©
OREGON
SAN PABLO BAY
©©
BOOECm bay
NEVADA
90UTHWTCN SHCW.
HUNTERS PONT
CALIFORNIA
©©
SWA MCNCA BAY
SEAL BEACH
mex^0
SAN OIEQO BAY
6AH BGOOHWBCR
CWtANDHAflBCR
«N PEDRO CANYCN
SEAL I
©»•
WNAPOW
©©© ©©©
Figure 4. (continued)
18

-------
AET exceedance was also more consistent among stations in each embay-
ment in the Northeast Region than in the remainder of the U.S. All four kinds
of AET were exceeded at all stations sampled in Salem Harbor, Boston Harbor,
West Long Island Sound, and Raritan Bay. At no other area in the remainder
of the U.S. were all four kinds of AET exceeded.
Based on the entire data set, the kind of AET exceeded most frequently
was the Microtox AET (84 cases). However, the benthic AET was exceeded
almost as often (77 cases). The amphipod and oyster AET were exceeded less
frequently (41 and 51 cases, respectively).
With respect to chemicals, 1-methylphenanthrene was the most frequently
exceeded AET (82 cases for all four AET). The exceedance rate for 1-methyl-
phenanthrene was similar (20 - 22 cases) for each individual AET. The high
exceedance rate for 1-methylphenanthrene reflects the relatively low AET for
this compound (310-370 ug/kg dry weight) when compared with non-alkylated
PAH (e.g., phenanthrene). Alkylated PAH such as 1-methylphenanthrene are
typically found in highest abundance relative to non-alkylated PAH in fuel oils.
Concentrations of mercury, PCBs, p,p'-DDD and p,p'-DDE also frequently
exceeded selected AET (>10 cases for all AET). In contrast to 1-methylphenan-
threne, these chemicals displayed distinct differences in the exceedances of
individual AET (Table 2). These differences suggest differential toxicity of the
chemicals for the four indicators. For example, PCBs exceeded the Microtox
AET at 29 stations, while the other PCB AET were exceeded at only one station
each. These results suggest a relatively high sensitivity of the Microtox
bioassay to PCBs (AET of 130 ug/kg dry weight). Alternatively, amphipods were
relatively insensitive to PCBs, with an AET of 2,500 ug/kg dry weight. Concen-
trations of most of the remaining chemicals either never exceeded AET or
exceeded AET at <5 stations.
Exceedances of AET by 1-methylphenanthrene concentrations in sediments
were confined to the Northeast region in embayments between Casco Bay and
lower Chesapeake Bay. Sediment concentrations of PCBs and mercury that
exceeded AET were much more widespread. PCBs exceeded the amphipod,
19

-------
TABLE 2. SUMMARY OF CHEMICALS THAT EXCEEDED THEIR AET
AT NOAA NATIONAL STATUS AND TRENDS STATIONS
Number of Stations Where AET Were Exceeded
Chemical*	Amphipod Oyster Microtox Benthic TOTAL
1 -Methylphenanthrene
22
20
20
20
82
Mercury
4
19
23
12
58
PCBs
1
1
29
1
32
p,p'-DDD
1
b
b
14
15
p,p'-DDE
4
b
b
9
13
Zinc
0
0
0
8
8
Silver
b
b
b
7
7
Anthracene
1
2
2
1
6
p,p'-DDT
3
1
0
0
4
2-Methylnaphthalene
1
1
1
1
4
Arsenic
1
1
1
1
4
Biphenyl
1
1
1
1
4
Naphthalene
1
1
1
1
4
Pyrene
0
2
2
b
4
Cadmium
1
0
1
1
3
Fluoranthene
0
1
2
0
3
Phenanthrene
Q
1
i
0
2
TOTAL
41
51
84
77

a The following chemicals did not exceed any kind of AET: acenaphthene,
fluorene, benzo(a)anthracene, chrysene, benzo(a)pyrene, dibenzo(a,h)anthracene,
hexachlorobenzene, copper, and lead.
b The indicated AET is not yet available for this chemical.
20

-------
oyster, and benthic AET only in Boston Harbor. However, the Microtox AET
for PCBs was exceeded in six northeast embayments, the St. Johns River
(Florida), San Diego Harbor and San Pedro Canyon (California), and the
Nisqually Reach in Puget Sound. Mercury displayed a similar pattern, with AET
exceedances in several northeast embayments, several areas in California, the
Nisqually Reach, and Lutak Bay in Alaska.
Because of the high frequency of AET exceedances by 1-methylphenan-
threne, changes were examined in the classification of stations resulting from
ignoring adverse effects predicted for this chemical. By ignoring these poten-
tial effects, five stations along the east coast were no longer predicted to have
adverse effects by any of the four kinds of AET. A reduction in predicted
effects would occur (i.e., fewer of the four kinds of AET would be exceeded by
any chemical) at 13 additional stations. All Salem Harbor, Boston Harbor, and
Raritan Bay stations were still predicted to be impacted by at least three of the
four kinds of AET. No changes in the classification of stations along the other
U.S. coasts resulted from ignoring predictions based on 1-methylphenanthrene.
The ratio of 1-methylphenanthrene concentrations to those of other hydro-
carbons (e.g., phenanthrene) is substantially higher in the Northeast Region
compared to data for all of the other regions of the country and may partly
explain why 1-methylphenanthrene concentrations exceeded AET so frequently in
that area.
The patterns of AET exceedance are examined in greater detail in Figure 5
for those areas in which one or more chemicals exceeded their AET at one or
more stations. The greatest number of chemicals exceeding a particular kind of
AET was found in Boston Harbor, where 20 chemicals exceeded their benthic
AET. Large numbers of chemicals (i.e., >10) also exceeded their AET in Salem
Harbor and Raritan Bay.
The maximum factor by which an AET was exceeded was found in Boston
Harbor (PCBs exceeded their Microtox AET by a factor of approximately 400).
Chemicals also exceeded their AET by a large factor (i.e., >10) in Casco Bay,
Salem Harbor, West Long Island Sound, and San Pedro Canyon.
21

-------
hEPRMACK RVER
HAFBCR
¦P--P-P--P
MAINE
0 M 8
VT
B06TCN H AffiOfl	A O M
*
NEW YORK I MASS
CONN
9LeZAPC6 WY
NAf+VCMSEU BAY
W LONG GLAw SOUND
PENNSYLVANIA XN J
iAAA
W. VA.
Atlantic
Ocean
VIRGINIA
RVTTAN BAY
NORTH CAROLINA
CBAWVC BAY
A 0 M
SOUTH
CAROLINA
LCV^R OtSAPEAHE BAY
20
GEORGIA
FLORIDA
«	ST. JOWSRNER
20
0 , ,	^
A O M B
LEGEND
NUM3ER0F
OEMCALS
ABOVE AET
10
¦10
MKXMJM FACTOR
ABOVE AET OF
ANY CUBICAL
100 200 300
, ML£S
| WLCMETERS
0 100 200 300 400 500
A O M 8
A.AMWCO
O-OYSTER
M.MCFIOTOK
B-B0/TWOS
Figure 5. Summary of the number of AET exceeded and the
maximum factor of exceedance
22

-------
GEORGIA
NEW MEXICO
Atlantic
Ocean
TEXAS
FLORIDA
y\N
MEXICO\
Gull of
Mexico
MSSS9PR R DH.TA
LEGEND
M*XMUM FACTOR
ABOVE AETCF
ANYCHEMCAL
100
200
300
Figure 5. (continued)
23

-------
LEGEND
rmcj B*Y
NUM3ER0F
CHEMCALS
ABOVE AET
M
MAXWUM FACTOR
AONEAETCF
ANYCHEMCAL
ALASKA
A.AWHPCO
0«0Y5TER
M-McnoroK
B.ranHoe
«?
NECUALLY REACH
nirrn bay
CGMJvK&JENT BAY
CANADA
WASHINGTON
Pacific
Ocean
SAN PABLO BAY
OREGON
QAWJW5 KAflBOR
CALIFORNIA
SEAJ. BEACH
SW DIEQO HARBCR
0 jn^Le^JZ^LsP
A 0 M B
SAN PEDRO CAtfllCN
4487	7778
0 100 200 300
MLES
WLQfcCTERS
0 100 200 300 400 500
Figure 5. (continued)
24

-------
The maximum AET exceedance for any chemical within a major chemical
group is presented in Figure 6 and Table 3 for each kind of AET. AET were
exceeded by metals over the widest area of the U.S. By contrast, AET exceed-
ance by a chemical within the LP AH group (frequently 1-methylphenanthrene)
was generally confined to the Northeast and Southeast Regions. Chemicals
within the HPAH group exceeded their AET only in Salem Harbor.
Overall AET exceedance was greatest in the Northeast Region, where AET
were exceeded in four of the five chemical groups in four areas (i.e., Boston
Harbor, Salem Harbor, West Long Island Sound, and Raritan Bay). In other
regions of the U.S., AET were not exceeded in more than three of the five
chemical groups in any area.
Although many chemicals were found to be below their AET (Table 3),
potential future problems area (or recently recovering areas) may be identified
by establishing a "safety factor" for screening stations. For example, a factor
of 0.5 times the AET could be used to identify stations approaching (or recently
declining from) the AET. Using such a factor, concentrations of chemicals were
near the AET in 22 study areas (Table 3). In five of those areas (i.e., Bodega
Bay, Columbia River, Dana Point, Hunters Point, and Mobile Bay) there were no
AET exceeded by any chemical.
COMPARISON OF PREDICTED EFFECTS AND OBSERVED EFFECTS
The AET predictions in the previous sections are based on comparisons of
chemical data for NOAA stations and AET values developed from chemical-
biological data in Puget Sound. In the following sections, predictions using AET
are compared with actual biological effects measured by NOAA and in other
programs. Measurements of the identical biological effect used to generate the
various AET were available in some, but not all, studies. For example, in the
NOAA Status and Trends Program, fish pathology data are used as measures of
biological effects; no data were available for sediment bioassays or benthic
infauna. Benthic infauna data were available in the SCCWRP and San Francisco
Bay studies. Bioassay data (amphipod mortality) were available only in the
NOAA San Francisco Bay study. The purpose of these comparisons was to
25

-------
CASCO BAY
MERRIMACK RIVER
LH HH Me Pe PCB
LH HH Me Pe PCB
SALEM
HARBOR
MAINE
LH HH Me
BOSTON
HARBOR
NEW YORK I MASS
CONN
LH HH Me
BUZZARDS BAY
NARRAGANSETT BAY
LH HH Me Pe PCB
LH HH Me Pe PCB
LEGEND
100 200 300
, MLES
| MLOfwCTHRS
0 100 200 300 400 500
MAXMUM FACTOR
ABOVE ACT Of
CHEMICALS wrmw
CHEMICAL GROUPS
A ¦ AMPWPOO ^
B ¦ BENTHOS O
U.MCR3TOX |
o.orsTEfl 1
UULPAH
W.h#>AH
M*a METALS
P# - PESTICIDES
PCB • PCB I
Figure 6. Summary of AET exceedance by chemical group
26

-------
MASS
NEW YORK
W. LONG ISLAND
SOUND
CONN.
PENNSYLVANIA
RARITAN BAY
MO
HH Me
PCB
W. VA.
VIRGINIA
HH
Me
PCB
NORTH CAROLINA
DELAWARE BAY
SOUTH
CAROLINA
LOWER CHESAPEAKE BAY
GEORGIA
HH Me
PCB
HH
Me
PCB
FLORIDA
ST. JOHNS RIVER
HH
Me
PCB
LEGEND
A ¦ AMPHtPOO
B.BEN TWOS
0.OYSTER
MAX MUM FACTOR
AOOVE AET OF
CHEMCALS WITHIN
100
300
200
Pa . PESTICIDES
100 200 300 400 500
Figure 6. (continued)
27

-------
GEORGIA
NEW MEXICO
ALABAMA
Atlantic
Ocean
MISSISSIPPI
LOUISIANA
FLORIDA
y^MExicoX
Gulf of
Mexico
v
MISSISSIPPI R
DELTA
LH HH Me Pb PCB
LEGEND
A.AMPWPOO
8-BENTHOS
M-MCFOTOX
0-OYSTER
UAXMJM FACTOR
ABOVE AETOF
CHEMICALS WITHIN
CHEMICAL GROUPS
LH-LPAH
HH ¦ HP AH
\M . METALS
P« - PESTICIDES
PCB ¦ PCfft
100 200 300
0 100 200 300 400 500
Figure 6
(continued)
28

-------
ELLIOTT BAY
CANADA
COMMENCEMENT BAY
WASHINGTON
PCB
HH Me
OREGON
NISQUALLY REACH
HH Me
PCB
SAN PABLO BAY
HH
Me
PCB
NEVA OA
OAKLAND HARBOR
PCB
HH Me
CALIFORNIA
SEAL BEACH
PCB
HH
Me
SAN PEDRO
CANYON
HH
PCB
Me

SAN DIEGO HARBOR
Me
PCB
HH
LEGEND
PCB
LH
Me
HH
BENTHOS
O. OYSTER
MAX MUM FACTOR
ABOVE AET OF
100
200
300
CHEMICAL GROUPS
Figure 6. (continued)
29

-------
ALASKA
NAHKU BAY
LUTAK INLET
LEGEND
MLES
KILOMETERS
MAXMJM fACTOfl
ABOVE A£TOf
CHEWCALS WITH IN
CHEM1CM.GA0UPS
A ¦ AMPMtPOO	V
B.BENTHOS	£
U.MCflOTOX |
O-OYSTEfl	H
LH ¦ LP AH
HH . HP AH
U*. metals
Pt. PESTICIOES
PC8 ¦ PCffi
Figure 6. (continued)
30

-------
TABLE 3. MAXIMUM FACTOR AT WHICH DIFFERENT AET WERE EXCEEDED"
BY A CHEMICAL IN EACH MAJOR CHEMICAL GROUP
Area
Type of
AETb
LPAH
HPAH
Metals
Pesticides
PCB
Appalachicola Bay
A
0.05
0.01
0.27
0.53*


B
0.04
0.02
0.42
0.02
0.01

M
0.04
0.03
0.24

0.11

0
0.04
0.03
0.17
--
0.01
Barataria Bay
A
—
	
0.10
_ _
_ _

B
—
0.01
0.32

	

M
--
0.01
0.19
--
--

0
--
0.01
0.13
--
--
Bodega Bay
A
0.02
—
0.21
_ _
_ _

B
0.02
—
0.34
--
0.01

M
0.02
—
0.51*
--
0.05

0
0.02
—
0.35
--
0.01
Boston Harbor
A
28.54
0.53*
2.66
5.46
20.22

B
28.54
0.79*
4.41
117.43
45.95

M
28.54
2.94
3.32
--
388.84

0
28.54
2.00
2.31
--
45.95
Buzzards Bay
A
6.76
0.11
0.19
1.52
0.25

B
5.66
0.07
0.44
1.83
0.56*

M
5.66
0.26
0.51*
--
4.77

0
5.66
0.21
0.36
--
0.56*
Casco Bay
A
10.58
0.20
0.13
_ _
0.04

B
8.87
0.13
0.30
--
0.09

M
8.87
0.46
0.34

0.73*

0
8.87
0.37
0.24
--
0.09
Charleston Harbor
A
0.06
0.05
0.16
0.04
0.01

B
0.05
0.03
0.29
0.06
0.01

M
0.05
0.15
0.16
--
0.10

0
0.05
0.08
0.11
--
0.01
Charlotte Harbor
A
	
0.01
0.02
_ _
..

B
—
—
0.03
--


M
—
0.02
0.07
--


0
--
0.01
0.05
--
--
Columbia River
A
0.02
	
0.16
_ —
0.01

B
0.01
--
0.45

0.01

M
0.02
0.01
0.75*
--
0.12

0
0.02
0.01
0.52*
--
0.01
31

-------
TABLE 3. (Continued)
Area
Type of
AET
LPAH
HPAH
Metals
Pesticides
PCB
Commencement Bay
A
0.20
0.02
0.27
0.13
0.02

B
0.17
0.02
1.45
—
0.04

M
0.17
0.10
0.14
--
0.38

0
0.17
0.06
0.14
—
0.04
Coos Bay
A
0.05
0.11
0.12
0.03
0.01

B
0.06
0.07
0.25
0.06
0.02

M
0.13
0.21
0.40

0.17

0
0.13
0.16
0.28
--
0.02
Corpus Christi Bay
A
—
	
0.13
	
_ _

B
—
—
0.45
--
	

M
—
—
0.20
—
__

0
—
--
0.14
--
—
Dana Point
A
	
	
0.18
0.04
..

B
0.01
--
0.42
0.07
0.01

M
0.01
—
0.90*
—
0.08

0
0.01
--
0.63*
—
0.01
Delaware Bay
A
1.72
0.01
0.15
0.09
_ _

B
1.44
0.01
0.33
0.19
	

M
1.44
0.02
0.24
—
0.04

0
1.44
0.02
0.17
—
—
E. Long Island Sound
A
0.02
0.01
0.10
	
0.01

B
0.02
—
0.25
	
0.02

M
0.02
0.02
0.20
	
0.19

0
0.02
0.02
0.14
—
0.02
Elliott Bay
A
0.23
0.25
0.28
0.15
0.18

B
0.22
0.15
0.67*
0.11
0.41

M
0.47
0.62'
0.27
—
3.49

0
0.47
0.37
0.27
—
0.41
Galveston Bay
A
—
0.01
0.08
	
_ _

B
--
--
0.23
	
--

M
--
0.02
0.11
	
	

0
—
0.01
0.08
—

Hunters Point
A
0.14
0.20
0.29
0.26
0.02

B
0.13
0.12
0.62*
0.06
0.04

M
0.28
0.39
0.37
—
0.38

0
0.28
0.31
0.26
—
0.04
Lower Chesapeake Bay
A
2.63
	
0.13
0.12
0.04

B
2.21
0.02
0.33
0.60*
0.09

M
2.21
0.02
0.29
—
0.74*

0
2.21
0.02
0.20
—
0.09
32

-------
TABLE 3. (Continued)
Area
Type of
AET
LPAH
HPAH
Metals
Pesticides
PCB
Lower Laguna Madre
A
	
	
0.14
_ _
_ _

B
—
—
0.22
--
--

M
--
—
0.10
--


0
--
--
0.07
--
--
Lutak Inlet
A
—
	
0.22
_ _
0.01

B
--
—
0.74*
--
0.01

M
—
—
1.38
--
0.12

0
--
--
0.96*
--
0.01
MACH
A
	
	
0.09
_ _
_ _

B
—
—
0.21
--


M
—
—
0.03
--
--

0
—
—
0.03
--
—
Merrimack River
A
5.16
0.23
0.07
_ «,
0.03

B
4.32
0.15
0.14
--
0.07

M
4.32
0.53*
0.15
	
0.63*

0
4.32
0.43
0.10
—
0.07
Mississippi River Delta
A
0.04
0.03
0.15
0.18
0.03

B
0.04
0.02
0.41
3.81
0.06

M
0.04
0.09
0.19
--
0.52*

0
0.04
0.05
0.13
--
0.06
Mobile Bay
A
0.02
0.01
0.24
0:11
_ _

B
0.02

0.66*
0.19
--

M
0.02
0.02
0.32
--
	

0
0.02
0.01
0.22
—
—
Nahku Bay
A
	
0.01
0.24
	
0.01

B
—
0.01
1.20
—
0.01

M
—
0.05
0.99*
—
0.10

0
—
0.03
0.69*
--
0.01
Narragansett Bay
A
3.41
0.12
0.29
0.22
0.11

B
2.86
0.07
0.75*
0.78*
0.25

M
2.86
0.25
1.46
—
2.09

0
2.86
0.19
1.02
—
0.25
Nisqually Reach
A
—
	
0.45
	
	

B
—
--
1.07
	
0.01

M
—
—
2.30
--
0.06

O
--
--
1.60
—
0.01
Oakland Harbor
A
0.04
0.10
0.57*
0.07
0.03

B
0.05
0.07
1.36
0.22
0.06

M
0.12
0.21
2.93
—
0.54*

0
0.12
0.15
2.03
--
0.06
33

-------
TABLE 3. (Continued)
Area
Type of
AET
LPAH
HPAH
Metals
Pesticides
PCB
Pamlico Sound
A
__ _
0.05
0.16
0.09
__

B
--
0.02
0.49
0.15


M
--
0.08
0.08



0
	
0.03
0.08
--
--
Raritan Bay
A
6.55
0.22
1.53
0.73*
0.19

B
5.49
0.09
3.65
9.47
0.44

M
5.49
0.45
7.83

3.72

0
5.49
0.33
5.44
--
0.44
Round Island
A
	
0.01
0.14
0.01
_ _

B
—
0.01
0.46
0.01
--

M
--
0.03
0.22
--


0
—
0.01
0.15
--

Salem Harbor
A
15.99
0.48
1.41
0.62*
0.32

B
13.40
0.70*
1.80
11.92
0.73*

M
13.40
1.28
3.59
--
6.19

0
13.40
1.01
2.49
--
0.73*
San Antonio Bay
A
0.06
	
0.06
	
_ _

B
0.05
--
0.20



M
0.05
—
0.04
--
--

0
0.06
—
0.03
--
--
Sapelo Sound
A
—
—
0.13
	
	

B
--
--
0.19
--
--

M
—
0.01
0.11
—
--

0
—
—
0.07
--
--
San Diego Bay
A
—
—
0.17
	


B
—
—
0.29
—
0.01

M
—
—
0.17
--
0.08

0
--
--
0.12
--
0.01
San Diego Harbor
A
2.21
0.25
3.19
0.33
0.21

B
3.23
0.33
3.49
0.56*
0.48

M
4.38
0.52*
1.76
--
4.02

O
4.38
0.38
1.41
--
0.48
Seal Beach
A
0.02
0.02
0.41
2.67
0.03

B
0.02
0.01
0.99*
4.44
0.06

M
0.03
0.06
2.12
--
0.49

0
0.03
0.03
1.47
--
0.06
Santa Monica Bay
A
0.01
	
0.15
0.27
0.01

B
0.01
0.01
0.25
0.44
0.02

M
0.03
0.02
0.07

0.14

0
0.03
0.02
0.05

0.02
34

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TABLE 3. (Continued)

Area
Type of
AET
LPAH
HP AH
Metals
Pesticides
PCB
San Pablo Bay
A
	
0.01
1.03
0.02
_ _

B
--
0.01
2.47
0.03
0.01

M
0.01
0.02
5.29

0.08

0
0.01
0.02
3.68
--
0.01
San Pedro Canyon
A
0.02
0.03
0.27
46.67
0.09

B
0.02
0.02
0.64*
77.78
0.19

M
0.03
0.05
1.37

1.64

0
0.03
0.04
0.95*
--
0.19
Southampton Shoal
A
0.11
0.10
0.17
	
0.01

B
0.19
0.11
0.33

0.02

M
0.41
0.36
0.06
--
0.15

0
0.41
0.25
0.06
--
0.02
St. Johns River
A
0.31
0.13
0.15
0.10
0.09

B
0.31
0.11
. 0.49
1.84
0.21

M
0.33
0.41
0.28
--
1.79

0
0.33
0.28
0.19
—
0.21
Tampa Bay
A
—
	
0.03
	
	

B
—
	
0.04
--
--

M
—
0.01
0.1
—
	

0
—
0.01
0.07
--
--
W. Long Island Sound
A
10.88
0.33
0.29
0.08
0.09

B
9.11
0.25
0.98*
1.13
0.22

M
9.11
0.71*
1.27
—
1.82

0
9.11
0.56*
0.88*
—
0.22
a Factors <1 but >0.5 are identified by an asterisk.
b A = Amphipod mortality bioassay
O = Oyster larvae abnormality bioassay
M = Microtox bioassay
B = Benthic effects (in situ)
c No data were reported
35

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the degree of correspondence between predicted and observed biological effects,
even when the kinds of effects differed.
NQAA Status and Trends Data Set
Results of the fish pathology comparisons are presented in detail in Tables
B1-B7 (Appendix B). Overall, significant elevations (P<0.05) in the prevalences
of liver lesions were found in 9 areas, whereas significantly elevated (P<0.05)
prevalences of kidney lesions were found in 23 areas.
A summary of the fish pathology results in relation to AET exceedance is
presented in Table 4. At the 19 study areas where an AET was exceeded at
one or more stations (Table 4), elevated prevalences of liver lesions were found
at 5 stations (26 percent) and elevated prevalences of kidney lesions were found
at 11 stations (58 percent).
Where an AET was not exceeded at any station, elevated prevalences of
liver lesions were found at 3 of the 19 areas (16 percent) sampled during the
NOAA Status and Trends survey. Elevated prevalences of kidney lesions were
found at 8 of those 19 areas (42 percent). Conversely, elevated prevalences of
liver lesions were not found at 14 areas where one or more AET were exceeded.
Elevated prevalences of kidney lesions were not found at 8 areas where one or
more AET were exceeded.
These data indicate that the exceedance of bioassay or benthic infauna
AET at individual stations is not well correlated with the prevalence of liver or
kidney lesions in the various study areas. However, elevated prevalences of
kidney lesions were found at 100 percent (10 of 10) of the embayments at
which AET were exceeded at multiple stations within individual embayments.
These latter results suggest a good correspondence between kidney lesions and
widespread contaminant effects in sediments. From this perspective, the
exceedance of AET over a wide area in an embayment may be an efficient
predictor of kidney lesions in fish. Additional data are required to determine
whether kidney lesions are a more sensitive indicator of contamination (and
therefore also occur in areas where AET are only sometimes exceeded), whether
36

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TABLE 4. SUMMARY OF FISH PATHOLOGY AT LOCATIONS
WHERE ONE OR MORE CHEMICALS EXCEEDED AN AET


Significant

No. Stations
Lesion

with an AET
Prevalence
Areaa
Exceeded
Liverb Kidney0
Casco Bay
1

Merrimack River
1

Salem Harbor
3
X
Boston Harbor
3
X X
Buzzards Bay
5
X
Narragansett Bay
3
X
W. Long Island Sound
2
X
Lower Chesapeake Bay
1

St. Johns River
2
X
Mississippi River Delta
2
X X
Nahku Bay
1
X
Lutak Inlet
1

Elliott Bay
3
X X
Commencement Bay
1
X X
Nisqually Reach
1

San Pablo Bay
1

Oakland Harbor
1

San Pedro Canyon
3
X
Seal Beach
2
X
a Although Raritan Bay, Delaware Bay, and San Diego Harbor each
had one or more stations at which an AET was exceeded, fish
pathology determinations were not made for those areas.
b 3 of 19 areas (16 percent) without an AET exceeded had signifi-
cantly elevated prevalences of liver lesions.
c 8 of 19 areas (42 percent) without an AET exceeded had signifi-
cantly elevated prevalences of kidney lesions.
37

-------
factors unrelated to sediment contamination influence the development of kidney
lesions in less contaminated areas, or whether chemicals not measured in the
Status and Trends Program could potentially account for the complete distribu-
tion of lesions.
Comparisons of spore densities of Clostridium perfrinaens with patterns of
AET exceedance are presented in Table 5. In general, spore densities increased
as an increasing number of chemicals exceeded their AET at each station. An
analysis of variance (ANOVA) conducted on the log-transformed densities
showed significant (P<0.05)among the five groups of values. A posteriori
comparisons showed that the groups with 0 and >5 chemicals exceeding their
AET were significantly different (P<0.05) from each other and from the other
three groups. The groups with 1, 2, and 3-4 chemicals exceeding their AET
were not significantly different (P>0.05) from each other.
These patterns indicate that changes in the densities of £4 perfrineens
were strongly associated with low, moderate, and high levels of biological
effects as predicted by the number of chemicals exceeding their AET. The
results do not necessarily imply that the contaminants exceeding AET are
sewage-derived because there was a poor correlation between the densities of
perfrineens spores and concentrations of these chemicals at individual stations.
However, the results suggest that biological effects predicted from the NOAA
Status and Trends chemical data are most often associated with contamination
from densely populated urban areas (which also discharge large amounts of
sewage).
Southern California Data Set
One or more chemicals exceeded their AET at 13 of the 71 stations (18
percent) sampled by Word and Mearns (1979) along the coast of southern
California (Table 6). All of these stations were located in the immediate
vicinity of municipal sewage outfalls in Santa Monica Bay (Stations 23-26), off
Palos Verdes (Stations 30-36), in San Pedro Bay (Station 45), and off Pt. Loma
(Station 69).
38

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TABLE 5. SPORE DENSITIES OF CLOSTRIDIUM PERFRINGENS
IN RELATION TO AET EXCEEDANCE
Number of Chemicals
Exceeding AET
Number of
Stations
Spore Density of Clostridium
perfrineens (number/g dry wt)
Mean Confidence Limits (95%)
0
61
445
176 - 714
1
32
1,535
572 - 2,498
2
7
1,514
649 - 2,379
3-4
7
3,779
977 - 6,581
>5
11
46,259
21,895 -70,623
39

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TABLE 6. SUMMARY OF CHEMICAL CONTAMINATION
AND BIOLOGICAL EFFECTS IN SOUTHERN CALIFORNIA"
Biological Effects
Chemical	Type	Reduced
Exceeding	of AET	Infaunal Echinoderm
Stationb	AET	Exceededc Index <69d Abundancee
23
Silver
PCBs
B
M
X
X
24
Silver
PCBs
B
M
X
X
25
Silver
B
X
X
26
PCBs
M
X
X
30
PCBs
M
X
X
31
Silver
Cadmium
Zinc
PCBs
B
A,0,M,B
B
0,M,B
X
X
32
Cadmium
Copper
Zinc
PCBs
A,0,M,B
B
B
a,o,m,b
X
X
33
Silver
Cadmium
Copper
Zinc
PCBs
B
A,0,M,B
0,M,B
A,B
A,0,M,B
X
X
34
Silver
Cadmium
Copper
Lead
Zinc
PCBs
B
A,0,M,B
0,M,B
M,B
a,o,m,b
A,0,M,B
X
X
35
Silver
Cadmium
Zinc
PCBs
B
A,0,M,B
B
0,M,B
X
X
40

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TABLE 6. (Continued)
Stationb
Chemical
Exceeding
AET
Type
of AET
Exceeded®
Biological Effects
Reduced
Infaunal Echinoderm
Index <69d Abundance®
36
PCBs
M

X
45
PCBs
M
X
X
69
PCBs
M


a Data are based on Word and Mearns (1979).
b No chemical exceeded an AET at the 58 stations not listed (i.e., of the 71
sampled).
c A = Amphipod mortality
O = Oyster larvae abnormality
M= Microtox
B = Benthic effects.
d 12 of the 58 stations (21 percent) not listed had Infaunal Index values <69.
e 8 of the 58 stations (14 percent) not listed had reduced echinoderm
abundances.
41

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Analyses of Infaunal Indices and echinoderm abundances indicate three
general areas of biological effects: Santa Monica Bay (Stations 23-29), Palos
Verdes Shelf (Stations 30-35), and San Pedro Bay (Stations 41-48). Biological
effects were found at all but 1 (Station 69) of the 13 sites at which an AET
was exceeded. The Infaunal Index was reduced below a value of 69 at 11 of
the 13 sites (84 percent), whereas the abundance of echinoderms was reduced
below 9 individuals/m2 at 12 of the 13 sites (92 percent). All of the stations
at which two or more kinds of AET were exceeded for one or more chemicals
displayed biological effects as evidenced by both low Infaunal Indices and low
echinoderm abundances. Moreover, benthic effects were always observed at
stations where the benthic AET was exceeded for one or more chemicals.
Station 69 was the only site in the southern California data set that exceeded
an AET but did not display biological effects according to the two benthic
indicators. It should be noted that the only AET exceeded at Station 69 was
the Microtox value for PCBs. As was previously described, the Microtox
bioassay appears to be much more sensitive to PCBs than the other biological
indicators.
Biological effects were found at 13 of the 58 stations (22 percent) at
which no AET was exceeded. The Infaunal Index was reduced at 12 of these
stations (21 percent) and echinoderm abundance was reduced at 8 stations (14
percent). These results would be expected because of the relatively few
chemicals measured in the southern California data set. For example, two of
the sites with low Infaunal Indices were identified by Word and Mearns (1979)
as being contaminated by petroleum from natural seeps. These sites could not
be identified by AET exceedance because the investigators did not measure
hydrocarbon concentrations in the sediments. Most of the remaining sites with
biological effects, but without exceedance of AET, were located in San Pedro
Bay in the vicinity of the Orange County Sanitation District sewage outfall.
The sediments of this area are much less contaminated by PCBs and DDT (the
only two organic chemicals measured) than sediments in Santa Monica Bay and
the Palos Verdes Shelf. Therefore, it is reasonable to assume that benthic
effects were caused by other factors such as organic enrichment or unmeasured
organic chemicals.
42

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San Francisco Bay Data Set
One or more chemicals exceeded their AET at two of the nine stations (22
percent; Table 7) sampled by Chapman et al. (1986, 1987) in San Francisco Bay.
Both of these stations (IS02, IS05) are located in Islais Waterway. Biological
effects were found at both of these stations. Significant amphipod mortality
(P<0.05) was found only at Station IS02. Significant mussel larvae abnormality
(P<0.05) and substantial benthic effects were found at both stations.
Biological effects were found at three of the seven stations at which no
chemical exceeded its AET. All three biological indicators showed impacts at
Station IS09, whereas only the mussel larvae abnormality test showed an impact
at Stations OA05 and OA09.
43

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TABLE 7. SUMMARY OF CHEMICAL CONTAMINATION
AND BIOLOGICAL EFFECTS IN SAN FRANCISCO BAY*

Station
Chemical
Exceeding
AET
Type
of AET
Exceededb
Amphipod
Mortality
Mussel
Larvae
Abnormality
Benthic
Effects
SP02 None
SP05 None
SP09 None
OA02 None
OA05 None	-- X
OA09 None	-- X
IS02 Mercury	MX	XX
Silver	B
Zinc	B
HPAH	M
Anthracene A,0,M,B
Chrysene	M
Dibenzo(a,h)-
anthracene	0,M
Fluoranthene	O.M
Pyrene	M
PCBs	M
IS05 Mercury	0,M,B X	X
Silver	M
Anthracene	A,0,M
Chrysene	M
Dibenzo(a,h)-
anthracene	A,0,M
Fluoranthene	0,M
Pyrene	M
PCBs	M
IS09 None	-- X	X	X
a Data are based on Chapman et al. (1986, 1987).
b A = Amphipod mortality
O = Oyster larvae abnormality
M= Microtox
B = Benthic effects.
44

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EVALUATION OF POLICY IMPLICATIONS
The integration of sediment criteria into environmental decision-making
processes requires consideration of a wide range of policy issues. These issues
derive from the differing emphases of regulatory programs as well as technical
considerations. An overview of regulatory applications of sediment criteria has
recently been released by the EPA Office of Water Regulations and Standards
(Battelle 1987). Examples excerpted from this report of the major legislative
authority for and potential application of sediment criteria are provided in
Tables 8 and 9 for perspective.
The purpose of the evaluation presented in this section is to examine the
implications of applying effects-based criteria as a tool for assessing coastal
sediment contamination. In addition, the implications of applying effects-based
criteria developed empirically for one region to coastal sediments in other
regions of the U.S. are addressed. This evaluation focuses on the following
topics:
~	Use of effects-based criteria as a tool in managing coastal
regions where both nonpoint and point sources may have
contributed to toxic buildup in sediments
~	Application of effects-based criteria at potential marine
Superfund sites
~	Apparent usefulness of effects-based criteria in addressing
remedial action policy issues related to "how clean is
clean."
Many of the issues addressed in this section are also being considered by
regional EPA offices, other federal, state, and local agencies, and private
interest groups. Discussion of critical issues in a work group setting or the
45

-------
TABLE 8. EXAMPLES OF MAJOR ENVIRONMENTAL LEGISLATION
RELEVANT TO SEDIMENT CRITERIA POLICY ISSUES (Source: Battelle 1987)
Law
Purpose
Clean Water Act of 1977
Section 115
Section 301
301(b)
301(h)
Section 402
Section 404
Clean Water Act of 1987
Section 104
Section 118
Section 304(a)
Establishes authority to restore and maintain the
chemical, physical, and biological integrity of the
Nation's waters.
Provides authority to identify the location of in-
place pollutants with emphasis on toxic pol-
lutants in harbors and navigable waterways.
Establishes effluent limitations.
Provides for effluent limitations for priority
pollutants from point sources, other than publicly
owned treatment works.
Modifies discharge permits for discharge from
publicly owned treatment works.
Authorizes the National Pollution Discharge
Elimination System (NPDES) for regulating the
discharge of pollutants from point sources.
Establishes permits for discharge of dredged or
fill material into navigable waters of the U.S.
Establishes authority to protect the chemical,
physical, and biological integrity of the Nation's
waters.
Establishes national programs for the prevention,
reduction, and elimination of pollution through
research, experiments, and demonstrations.
Requires annual reports on the status of pol-
lutants in sediments of the Great Lakes, and
removal of sediments with toxic pollutants.
Authorizes development and publication of criteria
reflecting the scientific knowledge on the
environmental effects of pollutants.
46

-------
TABLE 8. (Continued)
Marine Protection,
Research, and Sanctuaries
Act of 1972
Section 102
Section 103
Provides authority to regulate the transportation
for dumping and the dumping of material into
ocean waters.
Authorizes dumping permits for sewage sludge
and industrial wastes.
Authorizes permits for transportation of dredged
material for the purpose of dumping into ocean
waters.
Resource Conservation and
Recovery Act of 1976
Section 301
Toxic Substances and
Control Act
Section 4(a)
Section 4(e)
Authorizes efforts to promote the protection of
health and environment and to conserve valuable
material and energy resources by regulating the
treatment, storage, and transportation of
hazardous wastes that have adverse effects on
health and the environment.
Establishes criteria for identification and listing
of hazardous waste.
Authorizes regulation of chemical substances and
mixtures that present an unreasonable risk of
injury to health and the environment.
Authorizes development of testing methods
including toxicity testing.
Authorizes development of priority list
promulgation of procedures under Section 4(a).
for
Federal Insecticide,
Fungicide, and Rodenticide
Act
National Ocean Program
Act
Gives authority to protect health and environ-
ment against unreasonable adverse effects from
application of insecticides, fungicides, and rodent-
icide.
Confers authority to coordinate pollution programs
among the federal agencies involved in marine
research, monitoring, and regulations.
47

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TABLE 9. EXAMPLES OF POTENTIAL APPLICATIONS OF SEDIMENT CRITERIA IN IMPLEMENTING KEY ENVIRONMENTAL LEGISLATION (Source: Battelle 1987)


Clean-Up
Clean-Up



Durpsite Discharge
Permit Dunpsite Discharge Clean Area Area
Goal
Site
EIS

Designation Siting
Decisions Monitoring Monitoring Identification Selection
Setting
Restoration
Preparation
Clean Water Act (1977)





Section 104


X
X

Section 301
X
X XXX



Section 303, 304
X
XX X
X


Section 311

X X



Section 402

X X



Section 404
X
X X


X
1987 Clean Water Act Amenctnents




Section 118

X
X
X

Section 404

X



Section 405

XXX



Section 509
X
X X



Ocean Dunping Act





Section 102
X
X


X
Section 103

X



Resource Conservation and Recovery Act (RCRA)




Section 301

X



Section 1006
X
X


X
Section 1008
X

X


Section 3004


X


Section 3004G

X



Section 3005

X



Section 3019
X
X XX
X

X
Section 7003

X X



Section 9003

X X


X
Superfund Amencknent and Reauthorization ACT (SARA)
and Comprehensive Environmental Response and Liability Act (CERCLA)



Section 102/103
X
X X



Section 105

X X

X
X
Section 106

X X

X

Section 107

X X



Section 121
X

X
X
X
Section 205
X





-------
circulation of position papers may be effective in promoting an exchange of
viewpoints between these groups.
MANAGEMENT OF COASTAL SEDIMENTS
The NOAA Status and Trends program is designed to monitor temporal
changes at sediment stations that are generally removed from the direct
influence of point discharges. Because of their location, combined effects of
nonpoint sources and "far field" effects of multiple point sources of contamina-
tion can be assessed at these NOAA stations. In contrast, many stations
sampled in the SCCWRP program reflect direct contributions from sewage
outfalls in southern California. The potential for comparing the prediction of
biological effects at both kinds of stations was an advantage of the analyses
conducted for this report.
Four potential outcomes were possible from the prediction of biological
effects using Puget Sound AET:
1.	Adverse effects predicted at virtually all stations along the U.S.
coasts
2.	Adverse effects predicted at some sites, but in a random pattern
3.	Adverse effects predicted at some sites and in a trend corresponding
to an independent assessment of potential biological effects
4.	No adverse effects predicted.
Biological results reported in the NOAA and SCCWRP studies suggest that a
range of adverse effects might be expected at the monitoring stations used for
predicting biological effects. Hence, Outcomes 1 and 4 would indicate that the
AET approach is either too sensitive, too insensitive, or inappropriate for broad
application outside of Puget Sound. Outcome 2 might also indicate that the
approach was inappropriately applied, or at least that site-specific effects
criteria were required to interpret the results. Outcome 3 is closest to the
49

-------
results reported for this study, and suggests that effects-based criteria have
good potential for identifying problem sediments in coastal regions of the
United States and for distinguishing contaminated and uncontaminated regions.
Overall, the AET approach was useful in distinguishing NOAA Status and
Trends stations and areas by degree of predicted biological effects. The
relatively contaminated embayments of the Northeast Region were identified as
the most impacted areas in the U.S. By contrast, most embayments in the Gulf
Region were not predicted to exhibit biological effects. Predicted biological
effects in the Northwest/Alaska, Southwest, and Southeast Regions were
intermediate in magnitude between the effects predicted for the Northeast and
Gulf Regions. Thus, the AET approach was sufficiently sensitive to discriminate
among areas subjected to different degrees of chemical contamination.
Because the NOAA program was designed to monitor changes in sediment
chemistry at stations that are removed from the direct influences of point
discharges, the resolution obtained in this study suggests that an effects-based
approach can be used at areas removed from heavily contaminated areas (e.g.,
marine Superfund sites) to rank potential problem areas. The composition of
chemical contamination frequently varies among stations within regions and
among regions. Without consideration of potential biological effects, it is
difficult to determine, for example, whether an area contaminated with 1,000
ug/kg of PCBs should be ranked higher than another area contaminated with
1,000 ug/kg of mercury. The application of an effects-based approach to
sediment criteria provides a more uniform basis with which these areas can be
compared (the PCB contaminated areas would be predicted to be a problem
according to 1 of 4 AET indicators; the mercury contaminated area would be
predicted to be a problem according to 3 of 4 AET indicators and would be
ranked higher).
Comparison of the Status and Trends fish pathology results with the results
of the AET analysis showed that when the AET approach predicted widespread
biological effects (i.e., at multiple stations in an individual embayment),
significantly elevated prevalences of kidney lesions were found in 100 percent
of the cases. Therefore, in areas of widespread contamination, AET may be
50

-------
efficient predictors of kidney lesions. Far less correspondence was seen at
embayments in which AET were exceeded at none or only one of the stations.
Prevalences of liver lesions were elevated much less frequently than prevalences
of kidney lesions and showed no close relation with results of the AET analysis.
Given the fact that elevated prevalences of liver lesions were found in only one
of the highly contaminated embayments of the Northeast Region, it appears that
these abnormalities were not as sensitive to chemical contamination as were
kidney lesions.
Evaluations of the additional data sets from southern California and San
Francisco Bay generally supported the conclusions reached from the analysis of
the Status and Trends data set. That is, the AET approach was useful in
discriminating among stations subjected to different degrees of chemical con-
tamination along a pollution gradient. Using chemical data from the southern
California study, the approach identified impacted stations around sewage
outfalls that were similarly defined as impacted by an independent assessment of
benthic communities developed by Word and Mearns (1979). Evaluations of the
biological effects measured in both the southern California and San Francisco
studies showed that adverse effects almost always were found at the stations
where they were predicted to occur by the AET analysis.
A range of biological effects were predicted using the 1984 NOAA Status and
Trends chemical data. Hence, temporal changes in chemical concentrations at
these stations can be used to evaluate the extent of improvements in areas
predicted to be impacted or the potential increase in adverse effects in areas
exhibiting increasing sediment contamination. In addition, selective biological
monitoring could focus on those stations where changing sediment concentra-
tions are approaching AET values. Such monitoring would serve to verify
predictions and, over time, would potentially provide direct biological measure-
ments of the transition between normal and adverse conditions.
51

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IDENTIFICATION AND MONITORING OF POTENTIAL MARINE
SUPERFUND SITES
The empirical chemical-biological relationships incorporated in effects-based
criteria can provide a useful means for defining and monitoring the resolution
of problems at Superfund sites. Key questions to consider at potential Super-
fund sites include the following:
1.	Is the area contaminated?
2.	Does the contamination result in adverse biological effects?
3.	Is there a potential threat to public health?
4.	Can the contaminant sources be identified?
5.	Would remedial action reduce the environmental hazard?
Effects-based sediment criteria can be used as one of several tools to
address Questions 1, 2, 3, and 5. Prior to a remedial investigation at a
potential site, existing chemical data could also be assessed using such criteria
as part of a hazard ranking system. Although hazard ranking under current
Superfund programs focuses on human health considerations, consideration of
effects-based sediment criteria would add an environmental aspect to the
assessment at marine sites.
For problem identification, sensitive detection of contaminant-related
problems is typically required to enable a prioritization of sites for potential
remedial action. The AET approach used in this report was originally developed
and tested for this purpose at the Commencement Bay Nearshore/Tideflats
Superfund site in Puget Sound (Barrick et al. 1985). In addition, modified AET
developed using data from throughout Puget Sound have been applied by the
Puget Sound Dredged Disposal Analysis study as trigger levels for screening
decisions on the need for further chemical or biological testing and evaluation
52

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of dredged sediments proposed for marine disposal. The results of the analyses
conducted in the present report suggest that the AET approach has wider
applicability for problem identification at marine sites that could be considered
for listing on the National Priorities List. Confirmation of its applicability by
selective field testing is recommended.
From a policy perspective, the use of effects-based criteria beyond initial
problem definition hinges on legal defensibility (i.e., can the prediction of
effects be adequately supported to implement corrective action) and the cleanup
goal (discussed in the following section). In assessing the feasibility of
remedial action, modification of sediment criteria to incorporate a "safety
factor" or "multiplier" to either lower or raise the original criteria values may
be required. "Safety factors" can be used to ensure that contaminant-related
problems have been corrected, and to incorporate estimates of technical
uncertainties. "Multipliers" can be used to help prioritize remedial action by
identifying the worst problems (i.e., areas greatly exceeding sediment criteria)
to be corrected when resources are limited. Such modifications will typically
reflect site-specific needs or information. However, the procedure for assessing
information and selecting appropriate modifications would likely be consistent
among sites as a matter of policy. Other policy issues that frequently arise at
potential marine Superfund sites (and would benefit from use of effects-based
criteria) but that may require coordination with other regulatory programs
include:
o Identification of "acceptable sediments" for transfer among sites
(e.g., dredging and disposal programs evaluated under the Ocean
Dumping Act or Section 404 of the Clean Water Act)
~	Evaluation of the need for modified restrictions on discharges
regulated under Section 402 of the Clean Water Act [National
Pollution Discharge Elimination System (NPDES) program]
~	Identification of action guidelines for chemicals registered under the
Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) or Toxic
Substances Control Act (TSCA).
53

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REMEDIAL CLEANUP ISSUES
The identification of appropriate cleanup levels at remedial action sites
regulated under Superfund or Resource Conservation and Recovery Act (RCRA)
programs is a potential use of effects-based sediment criteria. Cleanup at a
remedial action site is controversial because few objective criteria exist for
quantitatively assessing more than the economic feasibility of cleanup actions.
A commonly expressed concern is that cleanup criteria based solely on biological
effects would likely be economically or technically infeasible. To address these
concerns, the following policy questions must be addressed:
~	What degree of environmental protection is desired or	required?
Should the degree of environmental protection vary among different
regions of the country or among sites that are used for	different
purposes?
~	What should determine an appropriate cleanup criterion?	Should
economic and technical feasibility be incorporated into the selection
of such a criterion? If so, what procedures should apply	to ensure
consistency among sites?
The goal of sediment remedial action is to alleviate contamination in problem
areas and thereby to eliminate associated adverse biological and human health
effects. Target cleanup goals should be those sediment contaminant concen-
trations that are not predicted to result in adverse biological effects. The
feasibility of such goals must be considered in the overall technical and
economic analysis of remedial action. Nevertheless, target cleanup goals should
be established based on an objective technical basis such as provided by
effects-based criteria. Local or regional conditions will often influence specific
cleanup decisions but a consistent process for making these recommendations is
desirable. In the event that target cleanup goals for certain chemicals are
found to be infeasible, then less stringent alternative criteria may be considered
and their implications noted.
54

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For example, the lowest AET for a range of biological indicators is a
potential tool for establishing cleanup goals. Implementation of such goals
would predict that, at concentrations below the goal, no adverse effects would
be expected according to any of the four biological effects indicators used to
generate AET. Comparable goals are under consideration as target sediment
cleanup levels in the Commencement Bay Feasibility Study in Puget Sound (PTI,
in preparation). Two sets of alternative cleanup levels (higher than the target
level and predicted to be less protective) are also being evaluated.
The NOAA Status and Trends stations evaluated in this study are generally
removed from direct contaminant discharges typically found at Superfund and
RCRA sites. Cleanup goals based on AET could require remedial action sites to
fall within the range of conditions found at the NOAA monitoring stations.
Approximately 65 percent of the 126 NOAA stations meet the lowest AET
(Figures 3 and 4) generated from Puget Sound data. Cleanup to such levels may
be feasible for only a small portion of a remedial action site but may be
warranted because of sensitive ecological concerns. A less stringent goal of not
exceeding two or more AET for a range of biological indicators would be met
by 71 percent of the NOAA Status and Trends stations. A still less stringent
goal of not exceeding all four AET would be met by 80 percent of these
stations (93 percent, if 1-methyl phenanthrene data are ignored). In addition,
the number of chemicals and magnitude of concentrations exceeding cleanup
goals can be used to resolve concerns over spurious results for individual
chemicals driving remedial actions.
RECOMMENDATIONS FOR FIELD STUDIES
The results of this study indicate that effects-based criteria may be recom-
mended for determining the extent and relative priority of potential problem
areas to be managed nationwide. This preliminary study should be augmented
by additional investigations, such as field studies under consideration by the
EPA Criteria and Standard Division for verification of the theoretical equili-
brium partitioning approach. It is recommended that tests be designed and
conducted to expand on the assessment of the applicability of both theoretical
and effects-based criteria among different geographic regions. The results of
55

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these chemical and biological tests can be used to validate the applicability of
effects-based criteria in areas other than where they were developed, provide
site-specific data should the criteria not be easily transferred among regions,
and also provide field verification of the predictions of the theoretical
approaches. Such tests will likely require the design of sampling and chemical-
biological programs in selected regions of the U.S. Refinements of the Puget
Sound AET and specific applications in Puget Sound are being further inves-
tigated by EPA Region X (PTI, in preparation) and cooperating federal and
Washington state agencies.
The use of site-specific sediment criteria should be encouraged until
adequate verification of any national sediment criteria has been completed. Use
of regional criteria (e.g., criteria based on Puget Sound AET) should be
supported by chemical-biological effects data in other regions as a test of their
applicability. Furthermore, in designing environmental monitoring programs and
interpreting monitoring results using effects-based sediment criteria, the
following questions should be addressed:
¦	What "biological effect" is being monitored?
¦	What combination of biological effects is appropriate to address
environmental concerns?
¦	To what extent can a particular combination of biological effects
serve as a surrogate for other effects?
It is also recommended that a review procedure be implemented to ensure
appropriate updating of the database used to set effects-based sediment criteria.
One draft approach to this concern is under review by the Puget Sound Dredged
Disposal Analysis study and the Puget Sound Estuary Program.
56

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REFERENCES
Barrick, R.C., D.S. Becker, D.P. Weston, and T.C. Ginn. 1985. Commencement
Bay nearshore/tideflats remedial investigation. Final Report. Prepared by Tetra
Tech, Inc. for the Washington Department of Ecology and U.S. Environmental
Protection Agency. EPA-910/9-85-134b. 2 volumes + appendices. Tetra Tech,
Inc., Bellevue, WA.
Beller, H.R., R.C. Barrick, D.S. Becker. 1986. Development of sediment quality
values for Puget Sound. Final Report. Prepared by Tetra Tech, Inc. under
contract to Resource Planning Associates for the Puget Sound Dredged Disposal
Analysis and Puget Sound Estuary Program. Tetra Tech, Inc., Bellevue, WA
Battelle. 1987. Regulatory applications of sediment criteria. Final Report.
Prepared for U.S. Environmental Protection Agency, Criteria and Standards
Division, Washington DC. 25 pp. + appendix. Battelle Ocean Sciences, Duxbury,
MA.
Chapman, P.M., R.N. Dexter, and S.F. Cross. 1986. A field trial of the
sediment quality triad in San Francisco Bay. NOAA Tech. Memo. NOS OMA 25.
U.S. Department of Commerce, Washington DC, 127 pp. + appendices.
Chapman, P.M., R.N. Dexter, and E.R. Long. 1987. Synoptic measures of
sediment contamination, toxicity, and infaunal community composition (the
Sediment Quality Triad) in San Francisco Bay. Mar. Ecol. Prog. Ser. 37: 75-96.
National Oceanographic and Atmospheric Administration (NOAA) 1987. National
Status and Trends Program for marine environmental quality: Progress report
and preliminary assessment of findings of the benthic surveillance project-
1984. Office of Oceanography and Marine Assessment, NOAA, Rockville, MD.
81 pp.
Word, J.Q. and A.J. Mearns. 1979. 60-meter control survey off southern
California. Tech Memo. TM 229. Southern California Coastal Water Research
Project. El Segundo, CA 58 pp.
57

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DEVELOPMENT OF SEDIMENT QUALITY VALUES
In the Puget Sound area, a comprehensive database is available that
indicates that sediment chemistry can be used for more than just providing
general information on the sediment. When properly analyzed, these data can
be interpreted to reveal general conclusions about chemicals present in a
sediment (and their concentrations) and biological effects that are associated
with the same sediments.
The AET approach has been used as one approach to develop sediment
quality values based on empirical evidence of biological effects. The empirical
relationships used to establish AET do not prove a cause-effect relationship
between contaminants and effects. However, in validation tests using indepen-
dent data sets, the approach predicted the occurrence of biological effects with
a high degree of accuracy (>80 percent for most biological indicators). Of the
various theoretical and empirical approaches examined, the AET (normalized to
sediment dry weight) was found to be the most predictive of the sediment
concentrations at which biological effects would always be expected. The
efficiency of individual AET in predicting only stations that actually had
biological effects was comparable to the efficiency of other approaches (approx-
imately 33 percent).
Sources of data used to develop AET for Puget Sound are summarized in
Figure A-l. Included in the database are data for sediment samples collected at
the major urban areas in Puget Sound (e.g., embayments adjacent to Seattle,
Tacoma, and Everett), as well as nonurban areas (e.g., "reference areas")
removed from major direct sources of contaminant discharges.
The focus of the AET approach is to identify concentrations of contami-
nants that are associated exclusively with sediments having statistically signi-
ficant adverse biological effects (relative to reference sediments). The approach
can be used for any chemical and for any observable biological effects (e.g.,
bioassays, infaunal abundances at various taxonomic levels, bioaccumulation). By
using these different indicators, application of the resulting sediment quality
values enables a wide range of biological effects to be addressed in the
management of contaminated sediments.
A pictorial representation of the AET approach for two chemicals is
presented in Figures A-2 and A-3 for a subset of these data (for amphipod
bioassay results in Puget Sound). Two subpopulations of all sediments analyzed
for chemistry and biological effects are represented by bars in the figures, and
include:
d Sediments that did not exhibit significant amphipod toxicity
~ Sediments that exhibited statistically significant (P<0.05) toxicity
in bioassays.
The horizontal axis in each figure represents sedimentary concentrations of
contaminant of concern (i.e., lead or 4-methyl phenol) on a log scale. For the
A-2

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TABLE A-1. PUGET SOUND AET FOR SELECTED CHEMICALS (DRY WEIGHT)
(ug/kg dry weight for organics; mg/kg dry weight for metals)

Amphipod
Oyster
Benthic
Microtox
Chemical
AETb
AETC
AETd
AETe
Low molecular weight PAH
5500f,g,h
5200
6100h
5200
biphenyl
260
260
270
270
naphthalene
24008,h
2100
2100
2100
2- methylnaphthalene
670
670
670
670
acenaphthylene
560
>560
640h
>560
acenaphthene
9808,h
500
500
500
fluorene
18008,h
540
640h
540
phenanthrene
54008,h
1500
3200h
1500
anthracene
1900f,g,h
960
1300h
960
1 -methylphenanthrene
310
370
370
370
High molecular weight PAH
380008,h
17000
>51000h
12000
fluoranthene
98008,h
2500
6300h
1700
pyrene
ll,0008-h
3300
>7300h
2600
benz(a)anthracene
30008,h
1600
4500h
1300
chrysene
50008,h
2800
6700h
1400
benzofluoranthenes
3700
3600
8000h
3200
benzo(a)pyrene
2400
1600
6800h
1600
indeno(l,2,3-c,d)pyrene
880|;1|
690
>5200h
600
dibenzo(a,h)anthracene
510
230
1200h
230
benzo(g,h,i)perylene
8608,h
720
5400h
670
Chlorinated organic compounds




Total PCBs
2500h
1100
1100
130
hexachlorobenzene (HCB)
130
230
230
70
p,p'-DDE
15

9
	
p,p'-DDD
43

2

p,p'-DDT
3.9
>6
llh
--
Metals




antimony
5.3
26
3.2
26
arsenic
93
700
85
700
cadmium
6.7
9.6
5.8
9.6
copper
800h
390
310
390
lead
700h
660
300
530
mercury
2.1h
0.59
0.88
0.41
silver
>3.7h
>0.56
5.2
>0.56
zinc
870h
1600
260
1600
a ">" indicates that a definite AET could not be established because there were
no "effects" stations with chemical concentrations above the highest concen-
tration among "no effects" stations.
b Based on 160 stations.
A-3

-------
TABLE A-l. (Continued)
c Based on 56 stations (all from Commencement Bay Remedial Investigation).
d Based on 104 stations.
e Based on 50 stations (all from Commencement Bay Remedial Investigation).
f A higher AET (24,000 ug/kg for low molecular weight PAH and 13,000 ug/kg
for anthracene) could be established based on data from an Eagle Harbor sta-
tion. However, the low molecular weight PAH composition at this station is
considered atypical of Puget Sound sediments because of the unusually high
relative proportion of anthracene. Thus, the low molecular weight PAH and
anthracene AET shown are based on the next highest station in the data set.
® The value shown exceeds the Puget Sound AET established in Beller et al.
(1986) and results from the addition of Eagle Harbor Preliminary Investigation
data (an area of heavy creosote contamination in Puget Sound).
h The value shown exceeds AET established from Commencement Bay Remedial
Investigation data (Barrick et al. 1985) and results from the addition of Puget
Sound data presented in Beller et al. (1986).
A-4

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APPENDIX A
SUMMARY OF
APPARENT EFFECTS THRESHOLD APPROACH

-------
LEAD
	NO SEDIMENT TOXICITY 	
•	I	***	_
•	• !••• • •	• 	 • • 		_
		SEDIMENT TOXICITY OBSERVED	~
\',U//./l//J/M/,.^			 H——
i	t	: i	i:
SP-15	SP-14	j RS-19	RS-18J
I	I
I	I
700 ppm	6300 ppm
j	1	1	1	1—i i i i|	1	1	1—i—1 ]	«	'	«—<—'I'M
10	100	j 1000	I 10.000
APPARENT MAXIMUM -J
AMPHIPOD OBSERVED
TOXICITY	LEVEL AT A
THRESHOLD BIOLOGICAL
STATION
CONCENTRATION (mg/Kg DW)
Figure A-2. The AET approach applied to sediments tested for lead concentration
and amphipod mortality during bioassays.

-------
OH
4-METHYL PHENOL (o)
	NO SEDIMENT TOXICITY	
•	M • •	• «M »» ¦ •«••• ««> «	•
SEDIMENT TOXICITY OBSERVED
I t i I	I!
RS-19 RS-18 J SP-1S	SP-14]
I	I
I	I
1200 ppb	I
	1	1	1	1—1—n—1|	1	1	1—1—1 1 1 1 | ^	1	1	1—1—1—% 1 f |	/ >	^
U10 100 1000	10.000 96.000
¦	I
APPARENT	MAXIMUM -J
AMPHIPOD	OBSERVED
TOXICITY	LEVEL AT A
THRESHOLD	BIOLOGICAL
STATION
CONCENTRATION (ng/Kg DW)
U - undetected at detection limit shown
Figure A-3. The AET approach applied to sediments tested for 4-methyl phenol
concentration and amphipod mortality during bioassays.

-------
The horizontal axis in each figure represents sedimentary concentrations of
contaminant of concern (i.e., lead or 4-methyl phenol) on a log scale. For the
specific biological indicator under consideration, the AET for lead is the highest
lead concentration corresponding to sediments that did not exhibit significant
adverse effects. The AET for 4-methyl phenol were determined analogously.
The Potential Effect Threshold (Figures A-2 and A-3) is the concentration
below which no statistically significant biological effects were observed in any
sample. Note that this threshold for 4-methyl phenol is equal to the detection
limit for the compound. The threshold is designated as "potential" because
toxicity was observed in some, but not all, of the samples from stations with
higher lead or 4-methyl phenol concentrations. The toxicity effects observed at
these stations could have resulted from other contaminants or physical
conditions (e.g., grain size). Because the potential effect threshold for a
chemical cannot be related in a meaningful way to the observed biological
effects, it is not used to set sediment quality values.
Apparent effects thresholds correspond to concentrations above which all
samples for a particular biological indicator were observed to have adverse
effects. Data are treated in this manner to reduce the weight given to samples
in which factors other than the contaminant examined (e.g., other contaminants,
environmental variables) may be responsible for the biological effect. For
example, sediment from Station SP-14 shown in Figure A-3 exhibited severe
toxicity, potentially related to a greatly elevated level of 4-methyl phenol (7,400
times reference levels). The same sediment from Station SP-14 contained a low
concentration of lead that was not critical in establishing the AET for lead
(Figure A-2). Despite the toxic effects displayed by the sample, sediments from
other stations with higher lead concentrations than Station SP-14 exhibited no
statistically significant biological effects. These results were interpreted to
suggest that the effects at Station SP-14 were more likely associated with 4-
methyl phenol (or a substance with a environmental distribution) than with lead.
A converse argument can be made for lead and 4-methyl phenol in sediments
from Station RS-18. Hence, the AET approach helps to identify different
contaminants that are most likely associated with observed effects at each
biologically impacted site. Based on the results for these two contaminants,
effects at 4 of the 28 impacted sites shown in the figures may be associated
with elevated concentrations of 4-methyl phenol, and effects at 7 other sites
may be associated with elevated lead concentrations.
If an unmeasured chemical (or group of chemicals) is not distributed in the
environment in the same way as a measured chemical (e.g., if a certain indus-
trial process releases an unusual mixture of contaminants), the effect should be
discerned if a sufficiently large data set is used to establish AET. Using lead
and the amphipod bioassay as examples, the amphipod bioassay AET for lead is
set by the highest lead concentration in samples that do n£l exhibit significant
mortality in the amphipod bioassay. Hence, the actual AET value will not be
influenced by the lead concentration in samples in which unmeasured chemicals
cause amphipod mortality. (Although the lead AET would not considered to be
established unless there is also at least one sample that does exhibit amphipod
mortality and has a higher lead concentration than the nonimpacted sample
setting the AET.)
A-8

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An unmeasured toxic chemical may occur in the environment with a
different spatial distribution than any of the measured chemicals. It is unlikely
that the AET approach could predict impacts at stations where such a chemical
is inducing toxic effects. However, the predictive success of AET can be tested
in a validation using an independent field data set. Such a test conducted
using Puget Sound data determined that AET identified from 82 to 94 percent of
the impacted stations, when the biological indicator was oyster larvae bioassays,
Microtox bioassays, or depressions in benthic infaunal abundances (Beller et al.
1986). Lower success was obtained with the amphipod bioassay (54 percent of
the impacted stations were identified), which may be related to an apparent
sensitivity of the amphipod bioassay to some fine-grained sediments even in the
absence of contamination (Beller et al. 1986).
The precision of the AET values was also estimated in the sediment quality
values work performed for the Puget Sound Dredged Disposal Analysis and Puget
Sound Estuary Program (Beller et al. 1986). Several potential error components
were considered, including the statistical error in incorrectly classifying one or
more nonimpacted stations that determined the AET. This classification error
was judged to provide a reasonable estimate of the 95 percent confidence
intervals for AET values.
A-9

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APPENDIX B
SUMMARY OF FISH
PATHOLOGY EVALUATIONS
B-l

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TABLE Bl. PREVALENCE OF HISTOPATHOLOGICAL CONDITIONS
IN WINTER FLOUNDER"
Location
Sample
Size
Kidney
MMC
Proliferation
Proliferative
Biliary
Hyperplasia
Hepatic
Neoplasia
Casco Bay
30
3
0
0
Merrimack River
30
3
0
3
Salem Harbor
30
40b
7
0
Boston Harbor
30
33b
10
13b
Buzzards Bay
30
17b
0
0
Narragansett Bay
30
13b
3
0
E. Long Island Sound
30
0
0
0
W. Long Island Sound
30
43b
0
0
a Each prevalence value was compared with 0 percent using the G-test.
b P<0.05.
B-2

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TABLE B2. PREVALENCES OF HISTOPATHOLOGICAL CONDITIONS IN SPOTa
Location
Sample
Size

Kidnev


Liver
Necrotizing
Granulomas
MMC
Proliferation
Hyalin
Lesions
Cholangio-
cellular
Necrosis
Hepato-
cellular
Necrosis
Upper Chesapeake Bay
30
0
0
13b
7
0
Lower Chesapeake Bay
19
0
0
11
5
11
Pamlico Sound
30
0
0
43b
0
10
Charleston Harbor
30
0
0
20b
7
20b
Sapelo Sound
30
0
0
73b
3
10
St. John River
17
12
35b
12
6
6
Charlotte Harbor
30
17b
17b
70b
0
17b
Apalachicola Bay
30
7
7
30b
0
53b
Round Island
30
0
3
17b
3
10
Mississippi River Delta
19
0
5
21b
5
16
Barataria Bay
29
0
0
7
0
0
Galveston Bay
17
0
0
0
0
35b
San Antonio Bay
30
0
7
7
0
0
Corpus Christi Bay
29
0
0
17b
0
0
a Each prevalence value was compared with 0 percent using the G-test.
b P<0.05.
B-3

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TABLE B3. PREVALENCES OF HISTOPATHOLOGICAL CONDITIONS
IN ATLANTIC CROAKER*
Location
Sample
Size

K.idnev


Liver
Necrotizing
Granulomas
MMC
Proliferation
Hyalin
Lesions
Cholangio-
cellular
Necrosis
Hepato-
cellular
Necrosis
Upper Chesapeake Bay
21
5
0
0
10
5
Lower Chesapeake Bay
30
3
3
7
10
0
Pamlico Sound
30
3
0
3
0
3
Charleston Harbor
36
0
3
3
33b
14b
Apalachicola Bay
30
0
0
7
0
10
Mobile Bay
21
0
5
24b
0
10
Mississippi River Delta
30
0
0
3
40b
13b
Barataria Bay
22
0
5
0
10
5
Galveston Bay
30
0
0
3
7
20b
Corpus Christi Bay
30
0
0
13b
0
0
Lower Laguna Madre
30
0
0
7
0
3
a Each prevalence value was compared with 0 percent using the G-test.
b P<0.05.
B-4

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TABLE B4. PREVALENCES OF HISTOPATHOLOGICAL CONDITIONS
IN ENGLISH SOLE AND FLATHEAD SOLE8
Location
Sample
Size
	Liver	
Foci of
Cellular Degeneration/
Alteration	Necrosis
Kidnev
Degeneration/
Necrosis
Proliferative
Disorders
Elliott Bay	60
Commencement Bay	30
Nisqually Reach	31
Elliott Bay	60
Commencement Bay	30
Lutak Inlet	30
Nahku Bay	30
English Sole
8b	38b
13b	10
3	0
Flathead Sole
0	3
0	38b
0	7
0	17b
12b
33b
0
13b
3
0
3
15b
13b
7
5
13b
0
0
a Each prevalence value was compared with 0 percent using the G-test.
b P<0.05.
B-5

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TABLE B5. PREVALENCES OF HISTOPATHOLOGICAL CONDITIONS
IN STARRY FLOUNDER*
	Liver			Kidney	
Foci of
Sample Cellular	Degeneration/	Degeneration/	Proliferative
Location Size Alteration	Necrosis	Necrosis	Disorders
Columbia River 31 0	6	10	6
Coos Bay 30 0	0	0	3
Bodega Bay 13 0	0	0	10
Southampton Shoal 16 6	0	38b	0
Hunters Point 28 0	0	14b	7
San Pablo Bay 30 3	0	10	0
a Each prevalence value was compared with 0 percent using the G-test.
b P<0.05.
B-6

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TABLE B6. PREVALENCES OF HISTOPATHOLOGICAL CONDITIONS
IN WHITE CROAKER®

Location
Sample
Size
Liver
Kidney
Degeneration/
Necrosis
Proliferative
Disorders
Degeneration/
Necrosis
Proliferative
Disorders
Bodega Bay
37
0
0
3
5
Southampton Shoal
30
0
0
7
3
Oakland Harbor
30
0
0
7
10
Hunters Point
12
0
0
0
0
San Pedro Canyon
29
3
0
3
14b
Seal Beach
30
0
3
7
30b
Dana Point
30
3
0
13b
3
a Each prevalence value was compared with 0 percent using the G-test.
b P<0.05.
B-7

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TABLE B7. PREVALENCES OF HISTOPATHOLOGICAL CONDITIONS
IN HORNYHEAD TURBOTa
	Liver			Kidnev	
Foci of
Sample Cellular	Degeneration/	Degeneration/	Proliferative
Location Size Alteration	Necrosis	Necrosis	Disorders
Santa Monica Bay 30 3	0	10	7
San Pedro Canyon 27 4	0	7	4
Dana Point 29 0	0	10	0
Seal Beach 210	0	0	5
San Diego Bay 18 0	0	6	0
a Each prevalence value was compared with 0 percent using the G-test.
b P<0.05.
B-8

-------