TP203 (POL-1117-202886) Non-target invertebrate ecological risk assessment for field corn expressing Cry34Ab1 and Cry35Ab1 insecticidal proteins.
Start time: 8:00 AM
Poletika, N¹, Storer, N¹, ¹ Dow AgroSciences LLC, Indianapolis, IN, USA
An ecological risk assessment was conducted to characterize the risk of adverse impacts of Cry34Ab1 and Cry35Ab1 insecticidal proteins expressed in Event DAS-59122-7 on non-target invertebrates found in or near corn agro-ecosystems. The ecological entities of value in this assessment were beneficial insects (predators and parasitoids), pollinators, detritivores, and incidentals, including endangered and threatened beetles. Characteristics of these entities requiring protection were population persistence of non-endangered and non-threatened species and individuals in local populations of endangered and threatened beetle species. No impacts were identified from comparison of toxicity test results to high-end exposure estimates. Initial field monitoring confirmed this conclusion. Endangered/threatened beetle species are not exposed to Cry34/35Ab1 proteins. Available data suggest Event DAS-59122-7 can be used to control western corn rootworm in field corn with minimal concerns for the safety of non-target organisms.

TP204 (RAM-1117-236446) Application of the Sequential Assessment of Lines of Evidence (SALE) Modified Weight of Evidence Approach to an Aquatic Ecological Risk Assessment.
Start time: 8:00 AM
Swanson, S¹, Ramesh, G¹, Duncan, W², ¹ Golder Associates Ltd., Calgary, Alberta, Canada² Teck Cominco Ltd., Trail, British Columbia, Canada
The Sequential Analysis of Lines of Evidence (SALE) approach is presented in a companion poster by Hull and Swanson. An example of the SALE approach to weight of evidence is presented herein for the benthic community of a large river. The first step in the SALE approach was to compare chemical (in this case metal) concentrations in sediment to regulatory criteria. This was done for upstream and downstream sites, and was used to rule out risks for chemicals of potential concern with concentrations less than criteria (step one of the SALE process). The second step was the scoring of laboratory and field lines of evidence relative to causal criteria. The lines of evidence included four toxicity tests (10-day survival and growth of Chironomus tentans, and 20-day survival and growth of Chironomus tentans, benthic community analyses (mean total abundance, total richness, percent dominance of most abundant taxa and combined abundance of sensitive organisms), and an evaluation of habitat quality. The laboratory toxicity tests showed a strong causal relationship and the changes in the benthic community showed a moderate causal relationship to metals in sediment. Indirect effects on habitat quality showed a weak-to-moderate causal relationship to metals in sediment. The third step was the evaluation and documentation of the magnitude of the observed response in each line of evidence (i.e., toxicity test, field community analysis, and habitat evaluation). The SALE weight of evidence summary integrated the information on the magnitude of response with the causal analysis for each site along the river. This summary showed that there are a few depositional areas which should be evaluated for potential risk management. However, risk management clearly is not warranted at several other areas, due to weak responses or weak causal relationships to metals in sediment, or both. The SALE analysis helps to ensure that the proposed risk management is appropriate to the measured or predicted ecological risks.

TP205 (STE-1117-843347) Draft environmental screening assessment of tetrabromobisphenol A (TBBPA) and two derivatives in Canada.
Start time: 8:00 AM
Pasternak, J¹, Suffredine, L¹, Stevenson, R¹, Taylor, K², ¹ Environment Canada, Pacific and Yukon Region, Vancouver, British Columbia, Canada² Environment Canada, Environmental Protection Service, Gatineau, Quebec, Canada
The Canadian Environmental Protection Act, 1999 requires that substances on the Canadian Domestic Substances List (DSL) which meet categorization criteria set out in the Act and Regulations undergo screening assessment in order to determine, in an expeditious manner, whether they present or may present a risk to the environment or to human health in Canada. The brominated flame retardant tetrabromobisphenol A (TBBPA) and two derivative compounds, ethoxylated TBBPA and TBBPA allyl ether, were identified for screening assessment based on chemical attributes which suggest they may be environmentally persistent and inherently toxic to non-human organisms. These substances are flame-retardants added to epoxy and polycarbonate resins used in the manufacture of products such as electronic circuit boards, communications equipment, and appliances. Release of these substances to the environment may occur during polymer processing operations, product service life and at disposal. TBBPA has been detected in all environmental media and in some biota. Uptake and accumulation have been demonstrated in some aquatic species although metabolism and excretion may limit bioaccumulation. Lowest aquatic toxicity values include a 96-h LOEC (shell development) of 0.018 mg/L in Crassostrea virginia, and a 72-h EC₅₀ (cell growth) range of 0.09-0.89 mg/L for Skeletonema costatum. TBBPA has also been shown to inhibit growth in some plants and reproduction in Eisenia fetida. Sublethal exposures in mammals have been associated with reduced hormone function and altered brain morphometry; in vitro studies suggest that TBBPA may be immunosuppressive. Fugacity modelling results suggest that TBBPA distributes predominantly into organic fractions of sediments and soils and as a result, the assessment will focus on organisms in these compartments. Although standard testing indicates low biodegradability, anaerobic conditions may allow transformation of TBBPA to bisphenol A, a potentially persistent and endocrine disrupting substance. The screening assessment of TBBPA and the two derivatives is underway.

TP207 (MCC-1117-832496) Genotoxicity Studies on mosquitofish, redear sunfish, and cricket frogs within a weight-of-evidence risk assessment.
Start time: 8:00 AM
Gillespie, A¹, McCarthy, C², Sciera, K³, Donnelly, K ¹, Matson, C¹, McDonald, T⁴, Sullivan, R³, Faught, B², ¹ Texas A&M University, College Station, TX, USA² CH2M HILL, Houston, TX, USA³ U.S.E.P.A, Dallas, TX, USA⁴ TDI Brooks International, College Station, TX, USA
Genotoxicity studies conducted on three species were used in a weight-of-evidence to assess ecological risk at the Hart Creosote Company Superfund Site in Jasper, Texas. Mosquitofish (Gambusia affinis) and cricket frogs (Acris crepitans) were collected in a small intermittent stream adjacent to the site. Juvenile redear sunfish (Lepomis microlophus) were collected from an on-site pond. Mosquitofish, cricket frogs, and redear sunfish were also collected from reference stations. Flow cytometric analyses were performed on all samples using 25 L of Gambusia and Lepomis blood/citrate buffer solution and dissected portions of Acris livers. Nuclear DNA content was analyzed on a Coulter Epics Elite flow cytometer (Beckman Coulter, Fullerton, CA, USA) by quantification using nuclear fluorescence. Half-peak coefficients of variation (HPCV) were calculated as an estimate of intra-individual genome size variability, a biomarker of chromosomal damage. Non-parametric ANOVA and Bonferroni corrected post hoc comparisons were used to evaluate the differences between receptors collected at the Hart site and reference sites. Whole-body chemical analysis of PAHs was performed on pooled tissue samples grouped according to HPCVs recorded in flow cytometry analyses. Co-located surface water and sediment samples were also analyzed for PAHs. Media chemistry results were compared to literature-based screening values. A weight-of-evidence assessment was completed for the amphibian and fish communities that included analyses of media chemistry, tissue residue, and genotoxicity as lines of evidence. There was a significant difference in HPCVs for Gambusia (p = 0.004) and Acris (p = 0.05) between the reference and Hart sites. Surface water screening values for fish and amphibians exceeded screening values for PAHs, as did measured tissue concentrations. All lines of evidence indicate that PAHs at the Site are genotoxic to both fish and amphibians. These results are similar to results determined for the benthic community in the same waterbodies based upon a weight-of-evidence approach that included media chemistry analyses, ex-situ toxicity tests of Hyalella azteca, species surveys, and analysis of crayfish tissue relative to literature screening values.

TP208 (JOH-1117-835163) Are South Chattanoogan residents and wildlife at risk to locally occurring contaminants: 1. Exposure Assessment.
Start time: 8:00 AM
Hussar, E.¹, Morris, C.¹, Campbell, M.², Lin, Z-Q^{1, 3}, Richards, S.², Johnson, K.^{1, 4}, ¹ Environmental Sciences Program, Southern Illinois University Edwardsville, Edwardsville, IL, USA² Department of Biological and Environmental Sciences, University of Tennessee at Chattanooga, Chattanooga, TN, USA³ Department of Biological Sciences, Southern Illinois University Edwardsville, Edwardsville, IL, USA⁴ Department of Chemistry, Southern Illinois University Edwardsville, Edwardsville, IL, USA
South Chattanooga, TN has been home to foundries, coke furnaces, chemical, wood preserving, tanning and textile plants for over 100 years. As a result of the dumping of wastes into the creek, subsequent flooding, run-off and atmospheric deposition the sediment and adjacent soil of Chattanooga Creek is contaminated with polycyclic aromatic hydrocarbons. Currently, 42 hazardous waste sites are located in South Chattanooga, 13 of these sites are listed as state or federal Superfund sites. Mixed among these sites are three large public housing complexes, schools, and single-family residences. Many of these public areas that surround the Chattanooga Creek are suspected of having multiple pollutants due to clandestine dumping and transfer via flooding. This concerns South Chattanoogans and ATSDR. To address these concerns, we focused on Arsenic and 16 PAH priority pollutants in residential and public areas of South Chattanooga, as well as the Chattanooga Creek floodplain. The overall goals of this exposure assessment are to measure the potential for exposure to PAHs from soils. The initial exposure estimate is incorporated into a probabilistic risk assessment for humans residing in South Chattanooga. Sixty samples were collected from 20 sampling sites (n=3 from each site) throughout Chattanooga neighborhoods, as well as along the banks of Chattanooga Creek. Arsenic was found in 100% of the samples and ranged from 19.7 mg/kg to 124 mg/kg. Benzo(a)pyrene was detected in 98.2% of the samples. B(a)P, benzo(a)anthracene, chrysene, and indeno(1,2,3-c,d)pyrene are all probable human carcinogens and were found ranging in concentration from not detectable to 21.9 ppm, not detectable to 13.2 ppm, 0.028- to 12.3 ppm, and 0.028- to 28.4 ppm, respectively. Total PAHs ranged from 0.35 ppm to 163 ppm. Preliminary indications are that there are areas that may pose risk to humans and wildlife as addressed in part two of the study.

TP209 (RAL-1117-837433) Probabilistic Risk Assessment of Soybean Rust Fungicides for Indiana.
Start time: 8:00 AM
Ralston-Hooper, K¹, Ochoa-Acuna, H^{2, 3}, Engel, B⁴, Hahn, L⁵, Shaner, G⁶, Lim, K⁴, Zhai, T⁴, ¹ Department of Forestry and Natural Resources, Purdue University² Department of Veterinary Pathobiology, Purdue University³ Department of Civil Engineering, Purdue University⁴ Department of Agricultural and Biological Engineering, Purdue University⁵ Office of the Indiana State Chemist⁶ Department of Botany and Plant Pathology, Purdue University
The recent introduction of Soybean Rust Phakopsora pachyrhizi into the U.S. has prompted the EPA to issue emergency exemptions for several unregistered fungicides. We determined the relative risks of water quality degradation from using these fungicides in the state of Indiana. The approach consisted of modeling the surface water concentration of 14 active ingredients resulting from their per-label use on agricultural land throughout the state. Fungicide losses at the edge of fields from the bottom of the root zone were estimated using the National Agricultural Pesticide Risk Analysis (NAPRA) tool developed by the Natural Resources Conservation Service, USDA. This tool provides soil-type and climate based probabilities of off-site pesticide loadings. Central- and upper-bound estimates were calculated for a simulation period of 40 y. The temporal and spatial extent of these concentrations were then used to calculate risks to aquatic biota and risks of exceeding both chronic and acute surface water concentrations calculated based on protection of human health. The results indicate that, for some fungicides, concentrations in some areas can be significant. In addition, the mode of action of some of these compounds (triazoles), as well as empirical data suggest that synergistic interactions with organophosphorous insecticides are possible. Based on these results, we propose that monitoring studies should be conducted to inform the development of best management practices.

TP210 (KAM-1117-841405) An alternative population level endpoint for use in ecological risk assessment.
Start time: 8:00 AM
Kaminski, L¹, Landis, W¹, ¹ Institute of Environmental Toxicology, Western Washington University, Bellingham, WA, USA
The goal of ecotoxicology is to understand the effects of anthropogenic stressors on the structure and function of an ecosystem. The focus of toxicological studies has historically been organismal, so much of the available data is based upon individual level endpoints. Environmental managers regulate based upon effects at higher levels of biological organization, which requires extrapolation from individuals to communities. The population is an intermediate level where individual effects can be used to predict population fate, which in turn can be used to model community level effects. The instantaneous rate of increase of an age structured population () has been proposed as a population level indicator, but there are several problems with it. First, is the theoretical rate of increase, and is only valid if the population has a stable age structure. Changes in age structure are likely when toxicants have age specific effects. Secondly, the use of to project into the future requires the assumption that the stable age structure will persist. And third, small changes in are almost impossible to detect in the field, and yet can have a large impact over a large projection interval. As an example, we studied a declining population of Pacific herring (Clupea harengus pallasi) to demonstrate that the instantaneous rate of increase was not constant for a population with an unstable age structure. We propose a population level metric for use in ecological risk assessment that incorporates the contribution of individuals to population persistence.

TP211 (BOO-1117-829805) Tools for Streamlining Ecological Risk Assessments at RCRA Corrective Action Facilities.
Start time: 8:00 AM
Booth, P¹, Gard, N¹, Bodishbaugh, D¹, ¹ Exponent, Bellevue, Washington, USA
The U.S. Environmental Protection Agency's (EPA) guidance for ecological risk assessment (ERA) consists of an 8-step process for evaluating chemical risks. This guidance was initially developed for application at Superfund sites. There are several important differences between Superfund sites where there is no longer any industrial activity and active industrial facilities that are under RCRA corrective action. Many of these differences result in inefficiencies when the 8-step process is strictly applied to a RCRA corrective action site. General Motors has been working collaboratively with EPA Region 5 to develop a set of tools that can be applied to ERAs being performed at GM's facilities that are undergoing RCRA corrective action to enhance the efficiency of the ERA process. GM has numerous sites subject to RCRA corrective action including assembly plants, parts plants, plating operations, and foundries. GM facilities range from those that are in urban areas, with all of the property utilized in some capacity (e.g., parking lots, buildings, process areas) to sites with large undeveloped areas associated with smaller active, industrial areas. Most facilities have storm water retention ponds and/or surface impoundments. Thus, many areas that may support habitat for ecological receptors are reserved for future industrial or commercial development or are components of the active industrial operations. The risk assessment tools are designed to streamline the ERA process by early identification and elimination of areas of the facility (a habitat screening) and application of a consistent set of screening values, list of receptors, assessment and measurement endpoints, and toxicity reference values (TRVs). These tools and the underlying technical approach are intended to form an ERA framework for each site, with modification as appropriate, to help in the efficient completion of ERAs.

TP212 (ERI-1117-829901) Exemestane (Aromasin) Environmental Fate and Ecotoxicity Overview.
Start time: 8:00 AM
Ericson, J¹, Huggett, D¹, Constantine, L¹, ¹ Pfizer Inc, Pfizer Global R&D, Chemical R &D, Environmental Sciences, Groton, CT, USA
Environmental fate, physical-chemical and ecotoxicology studies were conducted in support of an environmental risk assessment for the new chemical entity exemestane, a selective aromatase inhibitor used for the treatment of advanced breast cancer in postmenopausal women. A full summary of the environmental fate and effects data associated with exemestane will be presented. Exemestane is extensively metabolized with less than 1% excreted into wastewater treatment plants as unchanged drug. Subsequent wastewater treatment of these residues shows considerable biotransformation (k 1.8 hr-1) and mineralization (k 0.7 hr-1) during a typical hydraulic residence time and further biotransformation and loss once in the aquatic environment (k 0.06 hr-1). Such depletion indicates that exemestane will not persist once in the environment. Minimal sludge sorption (sludge Koc 2285) and soil sorption (Koc 1594-6533) indicate that these residues will mainly reside in the aquatic environment, but will not bioconcentrate (log P 2.5). Acute and/or chronic ecotoxicology studies with wastewater treatment organisms (EC50 > 1000 mg/L) and various environmental species (NOEC 48 hr. daphnia, 96 hr. rainbow trout, 72 hr green algae and 7-day ceriodaphnia 4.1, 1.9, 2.3 and 1.2 mg a.i./L, respectively) indicate aquatic effects are unlikely at relevant environmental levels.

TP213 (STA-1117-830883) Derivation of a Refined Predicted No-Effect Concentration for Bisphenol A: Application of Statistical Approaches versus Using Arbitrary Assessment Factors.
Start time: 8:00 AM
Staples, C¹, Henry, K², Woodburn, K², ¹ Assessment Technologies, Inc., Spotsylvania, Virginia, USA² The Dow Chemical Company, Midland, Michigan, USA
Environmental risk assessment is typically conducted by comparing concentrations of a substance to which one or more populations of organisms within a community or ecosystem are exposed with a concentration deemed unlikely to pose adverse effects to the organisms. This latter concentration is referred to here as a Predicted No-Effect Concentration (PNEC). PNEC values are most commonly derived by dividing the lowest no observed effect concentration (NOEC) from a set of toxicity studies by an assessment factor (e.g., 10 to 1000). Selection of the assessment factor is based on the quantity of available data. Fewer data warrant larger assessment factors and vice versa. This approach may be appropriate for substances with few toxicity data, but can be overly conservative for substances that have a large number of long-term studies. For well-studied substances, calculation of a PNEC may instead use statistical approaches that are designed to protect ecosystems and make use of the full distribution of NOEC values instead of a single value. Bisphenol A has an extensive set of aquatic toxicity studies covering numerous taxa including algae, Hydra, rotifers, mollusks, crustaceans (both benthic and pelagic), insects, annelids, fish and amphibians. Several recently completed tests are presented here. The full toxicity data set was used to calculate PNEC values using four methods: 1) the USEPA water quality criteria procedure, 2) the Hazard Concentration (HC5) approach, 3) development of a Species-Sensitivity Distribution, and, 4) using traditional assessment factors. The effect of additional data on these PNECs was assessed with sensitivity analyses to examine the impact of new information. The implication of these results will be discussed in light of current regulatory programs affecting Bisphenol A.

TP214 (JOH-1117-834567) Are South Chattanoogan residents and wildlife at risk to locally occurring contaminants: 2. Hazard Assessment.
Start time: 8:00 AM
Morris, C.¹, Hussar, E.¹, Campbell, M.², Lin, Z-Q^{1, 3}, Richards, S.², Johnson, K.^{1, 4}, ¹ Environmental Sciences Program, Southern Illinois University Edwardsville, Edwardsville, IL, USA² Department of Biological and Environmental Sciences, University of Tennessee at Chattanooga, Chattanooga, TN, USA³ Department of Biological Sciences, Southern Illinois University Edwardsville, Edwardsville, IL, USA⁴ Department of Chemistry, Southern Illinois University Edwardsville, Edwardsville, IL, USA
Due to the number of contaminated sites in the world, we are in need of methods to appropriately quantify risk in order to prioritize sites and focus remediation resources on those sites most affected. Ecological receptors are frequently more sensitive to contaminants than humans, particularly higher tropic level terrestrial or avian species, though the risk to these receptors is difficult to quantify without a reasonable degree of uncertainty. In the present study, an exposure assessment was performed on contaminants including polycyclic aromatic hydrocarbons (PAHs) and heavy metals present at 20 sites in residential and public areas of South Chattanooga, as well as the Chattanooga Creek floodplain. Contaminant data for soils was modeled to calculate estimated daily doses (EDDs) for three ecological receptors (deer mouse, short-tailed shrew and red-tailed hawk). Reference Toxicity Values (RTVs) for metals and PAHs were applied to these three receptors to perform a quantitative risk characterization. Hazard quotients (HQs) were calculated for all species using conservative RTVs. The risk assessment results enabled screening of the 20 sites for which soils data were initially collected, enabling focus of further investigative work to be narrowed to the most affected areas. At a selection of the sites within South Chattanooga, PAHs and arsenic were found to pose a potentially adverse level of risk (HQ>1) to terrestrial ecological receptors. For example the deer mouse had HQs up to 5.38 for indeno(1,2,3-cd)pyrene and 3.24 for arsenic at sites in South Chattanooga. Four sites (20 percent) were found to pose risk for one or more PAHs (HQ>1) during an initial screening, whereas seventeen sites (85 percent) were found to pose a risk for arsenic (HQ>1) when modeled for the deer mouse receptor.

TP215 (VAN-1117-791996) Derivation of ecologically relevant threshold concentrations for nickel in surface waters: an European perpective.
Start time: 8:00 AM
Van Sprang, P¹, Deleebeeck, N², De Schamphelaere, K², Heijerick, D¹, Janssen, C², ¹ European Center for Risk Assessment (EURAS), Gent, Belgium² Laboratory of Environmental Toxicology, University of Ghent, Gent, Belgium
In the framework of a mandatory Risk Assessment initiative, nickel specific information on environmental toxicity and on environmental exposure/fate for key environmental compartments (water, sediment, soil) was compiled in order to assess the potential impact of nickel to the environment. Since existing concepts and methodologies as laid down in the Technical Guidance Document have been mainly developed for organic compounds and are as such less suitable to assess the true potential impact of metals on the ecological quality of ecosystems, an innovative approach have been developed to derive ecologically relevant environmental effects threshold concentrations (PNEC) for nickel to the surface waters in different European countries. The proposed methodology encompasses the development of an extensive quality screened database containing chronic toxicity data for different freshwater taxonomic groups and takes the effect of metal speciation/competition on nickel toxicity fully into account by the use of newly developed chronic Biotic Ligand Models (BLM) for 3 different trophic levels (algae, invertebrates and fish). As such the freshwater nickel effects database can be easily normalised towards the geochemical conditions prevailing in the EU surface water under scrutiny. The statistical best fitting approaches that were used for the derivation of the freshwater PNECs from the species sensitivity distributions will be further discussed. Finally, the conservatism and remaining uncertainty considered for the final PNEC setting derivation will be highlighted and a way forward in order to reduce the uncertainties associated with metal risk assessments in general will be proposed.

TP216 (FRE-1117-822012) Site-specific dietary exposure assessment of several passerine bird species to PCDDs and PCDFs.
Start time: 8:00 AM
Fredricks, T¹, Zwiernik, M¹, Coefield, S¹, Seston, R¹, Moore, J¹, Tazlaar, D¹, White, T¹, Kay, D², Giesy, J^{1, 2}, ¹ Michigan State University, East Lansing, MI, USA² Entrix, East Lansing, MI, USA
Dietary exposures of passerine birds nesting in the Tittabawassee and Chippewa River floodplains near Midland, Michigan, were examined due to the presence of polychlorinated dibenzo–p–dioxins (PCDDs) and dibenzofurans (PCDFs) in both the terrestrial and aquatic food webs. Chemical production and manufacturing in Midland from 1897 to current is a possible source of the PCDD/PCDF compounds currently occurring downstream of Midland. Mean soil and sediment PCDD/PCDF concentrations were 10– to 20–fold greater downstream (target locations) of Midland compared to upstream (reference locations). Based on life history, site presence and availability of on and off site historical data, tree swallow, eastern bluebird, and house wren were chosen as passerine receptor species of interest. Dietary exposures were estimated from site-specific concentrations of representative food web samples of species available in the floodplain, combined with both a literature–based and site–specific dietary assessment for each receptor. Bolus samples collected from nestlings and adults were used to estimate site–specific dietary composition for each receptor species over the course of the breeding season. Seventeen 2,3,7,8 (PCDD/PCDF) congeners were measured and converted to 2,3,7,8–tetrachlorodibenzo–p–dioxin equivalents (TEQs) using avian WHO TEF values. Soil and sediment avian TEQs ranged from 3.95–24.8 (n=10) and 0.519–5.5 (n=10) ng/kg wet weight (ww), upstream of Midland while downstream TEQs ranged from 425–14700 (n=11) and 35.5–6060 (n=28) ng/kg ww, respectively. Aquatic (benthic and aquatic emergent) and terrestrial insect avian TEQs ranged from 0.296–32.3 (n=29) and 3.09–1570 (n=34) ng/kg ww upstream of Midland while downstream TEQs ranged from 0.42–4.15 (n=10) and 5.26–1900 (n=18) ng/kg ww, respectively. Estimated dietary exposure and average potential daily doses will be calculated and compared to literature values for receptor species. Since no species-specific dose response data exist for the majority of the PCDF congeners present, the estimation of risk from dietary sources is dependent on the selection of literature based effects thresholds.

TP217 (LIN-1117-823276) Development and Use of Biological Uptake Factors in Small Mammals at Longhorn Army Ammunition Plant.
Start time: 8:00 AM
Lindberg, Jonathan¹, Weisberg, Mark², ¹ The Shaw Group, Knoxville, TN, USA² The Shaw Group, Monroeville, PA, USA
A small mammal biological uptake study was conducted at Longhorn Army Ammunition Plant (LHAAP) to calculate site-specific bioaccumulation factors (BAF) for use in food chain models for an ecological risk assessment conducted at LHAAP. Uptake factors from abiotic media into organisms may be strongly affected by site-specific factors (e.g., chemical form of the element or compound, bioavailability, metabolism/excretion, and behavioral responses, such the ability of an organism to potentially sense and avoid contamination). Therefore, the use of in situ BAFs is extremely useful for developing realistic food chain models to calculate total daily doses. The Hispid Cotton Rat (Sigmodon hispidus) was selected as the target species for the following reasons: 1) it is commonly found at the Site; 2) the typical body weight of an individual provided a sufficient amount of tissue for the analysis of multiple suites of chemicals; 3) this species has a high contact rate with soil; and 4) it likely forms a prey base for higher trophic level organisms present in the area, such as the Red Fox and Red-Tailed Hawk. In addition to the Hispid Cotton Rats, a single shrew (Sorex spp.) was also collected and analyzed for body burden residues of metals. The shrew is an insectivore, and nearly its entire diet consists of earthworms. Therefore, it was included in the uptake factor analysis for informational purposes and to compare with concentrations detected in Hispid Cotton Rats. The site-specific BAFs showed that modeled small mammal tissue concentrations, based on BAF values from the literature, from soil and food-chain exposure overestimates body-burdens in mammals. Quantitative and qualitative comparisons of BAFs from on-site and reference areas, and between the Hispid Cotton Rats and the shrew, are also presented.

TP218 (DIC-1117-825942) Ecological Risk Assessment for Terrestrial and Aquatic Settings at the Jasper Creosote Facility.
Start time: 8:00 AM
dickman, d¹, mccarthy, c¹, sciera, k², faught, b¹, ¹ CH2M Hill, Houston, tx, usa² US Environmental Protection Agency, Dallas, TX, USA
A Baseline Ecological Risk Assessment (BERA) was conducted for the Jasper Creosoting Company Superfund Site (Site) in Jasper, Texas. Risks to ecological communities were characterized within three exposure areas including a forested wetland, an unnamed tributary, and Big Sandy Creek. A qualitative weight-of-evidence (WOE) was used to evaluate risk from PAHs and dioxins to identified plant, aquatic invertebrate, fish, and wildlife communities within the exposure areas. Data included benthic community structure (Shannon Diversity Index), fish community structure (index of biological integrity [IBI]), whole-body fish and crayfish tissue analyses, and bioassays of amphipods and wetland plants. These data were collected simultaneously with collocated media chemistry samples. Statistical analyses of bioassay results were compared against data for in-stream reference stations outside the influence of the Site and that are representative of conditions throughout the Big Sandy Creek watershed. Because benthic invertebrates are more sensitive than fish to PAHs and since the wetland and tributary are only seasonally inundated with water, fish were evaluated only in Big Sandy Creek where they live year round. IBI scoring and fish tissue residue analysis showed no risk to the fish community and that conditions were better than the upstream reference. For the benthic community, the amphipod bioassay results indicated toxicity only in the forested wetland. Historical macroinvertebrate community studies revealed similar results. The Shannon Diversity Index on macroinvertebrates for Big Sandy Creek showed better results downstream than at the reference. Crayfish tissue results showed no elevated concentrations of risk drivers from the Site. Plant bioassays showed no toxicity in any of the samples. Food–chain modeling revealed risks to wildlife in the wetland. The WOE suggests there are risks to wildlife and benthic invertebrates in the forested wetland, but not downstream in the tributary or Big Sandy Creek. The wetland is likely acting as a natural filter breaking down PAHs and organic by–products of the creosote plant that once operated upstream of the wetland before these constituents drain into Big Sandy Creek 800 feet downstream of the Site.

TP219 (KIM-1117-688234) Evaluation of ecological health in a stream impacted by acid mine drainage and its treatment using marine shell.
Start time: 8:00 AM
Kim, Kyoung-Woong¹, Kim, Ju-Yong¹, Shin, Kyung-Hee¹, Lee, Byoung-Tae¹, Lee, Kun-Young¹, An, Kwang-Guk², Kim, Jeong-Yeon³, Kwon, Young-Ho³, ¹ Dep. of Environmental & Engineering, GIST, Gwangju, South Korea² Dep. of Bioscience & Biotechnology, Chungnam National University, Daejeon, South Korea³ Research & Development Center, Halla Engineering & Construction Corp., Seoul, South Korea
Ecological health in a stream impacted by acid mine drainage (AMD) was evaluated using a multi-metric approach of the Index of Biological Integrity (IBI) based on natural fish assemblage. Recently, this approach has been widely applied to many developed countries as a tool for ecological risk assessments of water environments. We used 10 metric systems, instead of 12 metrics suggested by Barbour et al. (1999), for a development of the regional IBI model, and used trophic guilds, habitat guilds, and richness variables for the calculation of IBI values. In the model, four of eleven metrics were modified their attributes for the regional application. Values of IBI in the stream averaged 20.6 (n = 5), indicating a "poor condition" in the ecological health according to the modified criteria of US EPA (1993). Especially, Mean IBI values in the impacted sites of Site 2 and 3 were 13, and this health condition was recognized as "very poor condition". The IBI values in the impacted sites were significantly less than the value of the control. Also, we found that fishes in the site sites 2 and 3 were not present during the study and, morphological deformity of Rhynchocypris oxycephalus was found in the Site 4, influenced directly by the sites 2 and 3, indicating an chemical impact in the sites. From the results of experiments in which acid mine drainage was treated with marine shells at stagnant condition, pH increased up to 6.0 from 3.1, and Fe and Al were removed up to 99% within 6 hours. In the reactor experiment considering field application, pH of effluent maintained around 7.0. In addition, concentrations of Fe, Al and heavy metals decreased remarkably in the effluents, and bottom-opened screen between neutralizer basins showed high effectiveness in the treatment of acid mine drainage.

TP220 (KAY-1117-728406) PCDDs and PCDFs in Aquatic and Terrestrial Food Webs of the Tittabawassee River, Michigan.
Start time: 8:00 AM
Kay, D¹, Blankenship, A¹, Zwiernik, M², Jones, P², Newsted, J¹, Giesy, J², ¹ ENTRIX, Inc., East Lansing, MI, USA² Michigan State University, East Lansing, MI, USA
A preliminary sampling of aquatic and terrestrial food web items was conducted at two locations on the Tittabawassee River downstream of Midland (Imerman Park and Tittabawassee Township Park) and from one reference location located upstream at Sanford, Michigan. Concentrations of the seventeen 2,3,7,8 substituted PCDD/Fs congeners were used to calculate the TEQ concentrations in the soils, terrestrial plants, terrestrial invertebrates, earthworms, small mammals, sediments, aquatic plants, benthic invertebrates, crayfish, aquatic emergent insects, and fish at each of the sampling locations. TEQ values were based on mammalian World Health Organization toxicity equivalency factors. In most cases, the downstream locations had TEQ concentrations an order of magnitude greater than the upstream reference location. The two downstream locations exhibited similar congener profiles. Using Imerman Park as an example, six congeners accounted for more than 80% of the TEQ in both the aquatic and terrestrial food web items. The remaining congeners accounted for less than 5% of the TEQ when considered separately. In general, 2,3,4,7,8-PeCDF made the greatest contribution to the total TEQ concentrations across all matrices studied. At Sanford, the reference location, the same six congeners generally accounted for >70% of the TEQ with a more even distribution between 2,3,7,8-TCDD, 1,2,3,7,8-PeCDD, and 2,3,4,7,8-PeCDF. When the measured concentrations in biota were compared to biota concentrations previously predicted from sediment and soil concentrations, the model parameters resulted in an overestimate of the actual measured TEQ concentrations by more than 10-fold for invertebrates and 100-fold for small mammals. This comparison of predicted to measured values illustrates the importance of collecting site specific data to reduce uncertainty when considering food web exposures in environmental risk assessments.

TP221 (FIS-1117-738155) A Model of Food Avoidance Behavior and Risk of Acute Mortality for Birds and Mammals Exposed to Acutely Toxic Chemicals.
Start time: 8:00 AM
Fischer, D¹, Barfknecht, R², Grau, R², Hart, A³, Luttik, R⁴, ¹ Bayer CropScience, Stilwell, KS, United States² Bayer CropScience, Monheim, Germany³ Central Science Laboratory, DEFRA, York, United Kingdom⁴ RIVM, CSR, Utrecht, The Netherlands
In the laboratory, birds and mammals commonly reduce their feeding rate when exposed to food spiked with acutely toxic chemicals. This response may reduce the likelihood of lethal intoxication in the field, but is usually ignored in risk assessments due to uncertainty about whether avoidance will be occur under various feeding scenarios that may occur in the field. Here, we present a model for predicting when avoidance will occur and whether it will prevent lethal intoxication. Key factors that influence risk of intoxication are its feeding rate, the toxicant concentration it its food, the size of the difference between dose thresholds for avoidance and lethality, and the latency (time delay) between ingestion of a dose and subsequent avoidance. This model explains why lethal intoxication may result from some feeding scenarios and not others, and provides a means of extrapolating standardized laboratory tests results to a wide range of field exposure scenarios. Application of the model to a real-world pesticide use scenario is presented.

TP222 (BOV-1117-742674) Ecological Risk Assessment of the Former Nansemond Ordnance Depot, Suffolk, Virginia.
Start time: 8:00 AM
Bovitz, Paul¹, Brown, Ryan¹, Opdyke, Cliff², ¹ Weston Solutions, Inc, Edison, NJ, USA² US Army Corps of Engineers, Baltimore District, Baltimore, MD, USA
The Former Nansemond Ordnance Depot (FNOD) consists of 975 acres of land formerly used as an Army ammunition depot located in Suffolk, VA. During World Wars I and II. The ecological risk assessment of the FNOD site, completed as part of the remedial investigation (RI), focused on two potential source areas: the 32-acre Main Burning Ground/Steamout Pond Area and the 10-acre Horseshoe Pond Area. The objective was to conduct a detailed site-specific assessment of ecological risks focused on principal contaminants of concern at the site (polycyclic aromatic hydrocarbons, pesticides, and metals), sufficient to provide the basis for risk management decisions for these contaminants in soil and sediment within the two source areas. Field studies were undertaken in spring 2004. Small mammals and amphibians were collected for tissue analysis used for hazard quotient modeling to determine whether there were impacts to the food chain from site contamination. Histopathology analysis was undertaken to determine whether small mammals were impacted by contamination. Sediment bioassays were conducted to determine if pond sediments were toxic. Data were collected to determine if there were any contaminant impacts on the benthic macroinvertebrate community structure in Horseshoe Pond and Steamout Pond. Results of the investigation were used to demonstrate that sediments within both ponds were not toxic relative to an off-site reference location, and there were no major impacts to benthic macroinvertebrate community structure. No direct contaminant impacts to small mammals were noted by histopathology, and results from hazard quotient modeling indicated no significant ecological risks from contamination to higher receptors. Hazard modeling of soil to earthworms to American robins indicated there may be ecological risks related to polycyclic aromatic hydrocarbons, pesticides, and metals. However, follow-up studies indicated this is not likely a complete exposure pathway due to the paucity of soil invertebrates actually present in site soils.

TP223 (NAI-1117-777140) Modelling the population-level ecological risks of dioxinlike PCBs on fish-eating birds from Tokyo Bay and its vicinity.
Start time: 8:00 AM
NAITO, W¹, ¹ National Institute of Advanced Industrial Science and Technology, Research Center for Chemical Risk Management, Tsukuba, Ibaraki, Japan
Population-level ecological risk assessments of dioxinlike PCBs on fish-eating birds was performed to judge the need for risk management measures to protect aquatic wildlife from dioxinlike PCBs contamination in Japan. Egg mortality risk and the changes in population growth rate, , in relation to the contamination levels of dioxinlike PCBs in eggs of four different types of fish-eating birds were determined by integrating the results from both bioaccumulation and life-history models. Assuming dioxinlike PCBs contamination levels observed in the Tokyo Bay and its vicinity, egg mortality risks for grey heron, great cormorant, osprey and kingfisher populations were 5.8, 6.8, 12 and <1 %, respectively. The estimated for grey heron, great cormorant, osprey and kingfisher populations were all greater than one, in case of the current dioxinlike PCBs contamination levels observed in the Tokyo Bay and its vicinity. Judging from the results of the analyses, current contamination levels of dioxinlike PCBs observed in the Tokyo Bay and its vicinity pose little risk on the fish-eating bird populations, thus, along with a decreasing trend of dioxin and dioxinlike PCBs levels in the Tokyo Bay, there is at present no need for urgent risk reduction measures for protecting fish-eating bird populations for dioxinlike PCBs.

TP224 (RAI-1117-559257) Modeling stressor impacts on population growth rate and extinction risk.
Start time: 8:00 AM
Raimondo, S.¹, McKenney, C.¹, Barron, M.¹, ¹ U.S. EPA/Gulf Ecology Division, Gulf Breeze, FL, USA
Population structure and life history strategies are determinants of how populations respond to stressor-induced impairments in individual-level responses, but a consistent and holistic analysis has not been reported. Effects on population growth rate were modeled using five theoretical constructs that represented the life history strategies and elasticity patterns (proportional sensitivities) of a broad range of species. Simulations of low to high ranges of simultaneous reductions in survival and reproduction indicated that stressor impacts on population growth rate were dependent on population characteristics and the magnitude of the stressor. Perturbation simulations were performed to assess the extinction risk in two species with similar elasticity patterns but different life history strategies: mysid shrimp, Americamysis bahia, and the gypsy moth, Lymantria dispar, K- and r-strategists, respectively. Extinction risk was greater for the K-strategist which indicated that population level risks were dependent on life history strategies, and toxicity values (e.g., LC50s) should be interpreted relative to population characteristics. Toxicity test data of mysids exposed to 53 toxicant-concentrations (10 toxicants, 5-6 concentrations each) were used to validate the predictability of the simulation method to determine the decline in population growth rate from different combinations of reduced survival and reproduction. The results of the simulation modeling suggest that the ecological risks of stressors on populations will be dependent on the elasticity patterns and life history strategies in addition to the magnitude of effects on organism-level endpoints.

TP225 (LEE-1117-591824) The Evaluation of Releasae Estimation Methods of KORECORisk Program.
Start time: 8:00 AM
Lee, Y.-J.¹, Kim, K.¹, Kim, Y.-H.¹, ¹ Korea Institute of Toxicology, Daejeon, Republic of Korea
KORECORisk (KORea ECOlogical Risk) program has been developed to pin point the hot industrial spot in ecological risk. The peculiarity of the program is estimation of the risk using the chemical inventory data of Korea and the physicochemical data. We are in the process of refining the predictability of the program. Daejeon has been selected as a target industrial area to evaluate the accuracy of release estimation methods of the program and assess the ecological risk at a regional scale. We applied release estimation methods to water environment with a step-by- step approach. Firstly, emission factors (EF) were divided into two classes by pesticide and others. Secondly, we divided emission factors into 16 classes by industrial/use category (Ref. EURAM). Finally, biodegradation in the treatment step has been incorporated to the release estimation method, in addition to the existing processing step. Three phthalates and five volatile organic compounds (VOCs) were chosen for field monitoring based on the risk estimated by the KORECORisk and the availablility of analytical methods. The concentrations of these target chemicals in the effluent were monitored and the accuracy of release estimation methods was calculated. As a result, an accuracy factor, the ratio of PEC (Predicted Environmental Concentration) to MEC (Measured Environmental Concentration), for phthalates was within the range of ten. On the other hand, the concentrations of VOCs was overestimated and the emission factors need further to be improved. Also, 128 compartments divided based on the watershed of Daejeon could represent relative ecological risks caused by industrial chemicals in different colors. Other industrial regions would be included in this model and evaluated through further study.

TP226 (YOK-1117-594835) Ecological impact assessment of pesticides using caddis fly larvae, Cheumatopsyche brevilineata (Iwata).
Start time: 8:00 AM
Yokoyama, A¹, Ohtsu, K¹, Ishihara, S¹, Kobara, Y¹, Horio, T¹, Endo, S¹, ¹ National Institute for Agro-Environmental Sciences, Tsukuba, Ibaraki, Japan
Despite of a potential risk of pesticides runoff from rice paddy fields to rivers in Monsoon Asia, it is difficult to assess appropriately the ecological impacts of pesticides in the river because of lacking test organisms representing aquatic biota in river ecosystem. Our research purpose is to develop methods of ecological impact assessment of chemicals including pesticides using riverine insects. Caddis fly is a kind of typical riverine insects and an important primary consumer in river ecosystem in Monsoon Asia. We were first to succeed in the indoor breeding of caddis fly, Cheumatopsyche brevilineata (Trichoptera, Hydropsychidae) as a test organism and establish methods of acute toxicity tests using first- and 5th- instar larvae. The sensitivity to fenitorothion (an organophosphorus insecticide) of first-instar larvae did not change through three successive generations in laboratory cultures. Chematopsyche from different regions in Japan, possesses a wide range of sensitivity to fenitorothion. These results suggest that this caddis fly species can be reared easily in the laboratory condition and use as a tool for the ecological impact assessment.

TP227 (JUD-1117-656111) Deriving Ecologically-Based Remedial Action Levels for Soil Metals in a Forested Wetland Using Iterative Methods.
Start time: 8:00 AM
Judd, L.¹, Peterson, S.¹, Essick, C.¹, Baines, A.¹, Devan, R.¹, Dulcey, R.², ¹ Environmental Resources Management (ERM), Exton, PA, USA² Environmental Resources Management (ERM), Ewing, NJ, USA
An approach for developing ecological cleanup goals based on USEPA risk assessment guidance was used to delineate an area of metals-impacted forested wetland soils at a Superfund Site located in southeastern Pennsylvania. The Site contains a 17-acre forested wetland adjacent to an intermittent headwater stream. A wildlife exposure model for the Site identified arsenic, cadmium, chromium, lead, and zinc in a portion of the wetland soils (and related drainages) as having potential ecological risk. Using this model, site-specific preliminary remediation goals (PRGs) were calculated to define an acceptable average exposure level within the area of concern. The method of iterative truncation was then used to estimate the extent of soil removal necessary to reduce wildlife exposures to below PRGs. Iterative truncation involves successively removing samples with the highest constituent concentrations, replacing them with a background concentration (representing clean fill), and recalculating exposure until risk is acceptable. At the end of this process, the remedial action level (RAL) is defined as the maximum concentration that can be left in place within the study area and the spatial extent of metal-impacted soils exceeding the RAL can be delineated. Each of the constituents was examined independently using this approach, and it was found that chromium risk was the main driver for Site cleanup. Additional sample locations with concentrations less than the RAL were included in the principal metal-impacted area based on practical considerations (e.g., proximity). Removal of soils from this area is estimated to achieve a risk reduction of greater than 82% for the constituents of concern.

TP228 (EAD-1116-606924) Monitoring of environmental fingerprints of alcohol ethoxylates in Europe and Canada.
Start time: 8:00 AM
Eadsforth, Charles¹, Sherren, Andrew¹, Selby, Martin ¹, Toy, Robin², Eckhoff, William³, McAvoy, Drew³, Matthijs, Eddy⁴, ¹ Shell Global Solutions (UK), Chester, UK² Shell Chemicals Ltd., London, UK³ The Procter & Gamble Company, Cincinnati, USA⁴ N.V. Procter & Gamble Eurocor S.A., Strombeek-Bever, Belgium
Recent improvements in methodology for the determination of alcohol ethoxylates (AE) in effluents now enable measurement of the full range of AE components, at ng/L levels, in the same analysis. This approach was deployed in effluent monitoring of biofilm and activated sludge waste water treatment plants from Europe (n=12) and Canada (n=8) receiving predominantly municipal effluent. Individual component or 'environmental fingerprint' analysis for alkyl carbon numbers C₁₂-C₁₈ and ethoxylate numbers 0-18 was conducted using a derivatisation procedure with LC/MS determination. The AE results were very similar with an overall mean level of 5.7 ug/L (range 1.0 - 22.7 ug/L). The major contribution to the total AE content was from fatty alcohol, which constituted, on average, 43% of the total. The exposure data can then be corrected to account for alcohol derived from sources other than AE and for sorption to particulate matter to determine AE concentrations in undiluted effluents. These data can then be used with site-specific dilution information to estimate river water exposure in mixing zones and then to determine aquatic risk by integrating normalised AE effect concentrations determined through quantitative structure activity relationships (QSARs).

TP229 (MOO-1122-225557) Tissue Residue Concentrations of PCDDs and PCDFs in Megaloptera: A Comparison to Other Benthic Invertebrate Orders.
Start time: 8:00 AM
Moore, J¹, Park, C¹, Zwiernik, M¹, Kay, D², Tazelaar, D¹, Hamman, D¹, Giesy, J¹, ¹ Michigan State University, East Lansing, MI, USA² ENTRIX, Inc., Okemos, MI, USA
Traditionally, collection and chemical analysis of benthic invertebrates for food web studies is hampered by difficulty in obtaining samples that appropriately reflect community diversity and provide sufficient sample mass for chemical analysis. Rather than the collection and analysis of complete communities, insects in the order Megaloptera (i.e., alderflies, dobsonflies, fishflies) may serve as a representative benthic invertebrate for maximal exposure estimates such as in screening-level exposure assessments. Megaloptera larvae are in contact with sediment for two to five years, have high lipid content, and are opportunistic feeders. In addition, they are relatively easy to collect in most river systems and have large body masses. A previous study on the Kalamazoo River (MI) showed that PCB concentrations in Megaloptera were not significantly different compared to five other benthic invertebrate orders sampled at the same locations. In the present study, residues of seventeen 2,3,7,8 substituted PCDD/Fs congeners were used to calculate the TEQ concentration in Megaloptera from PCDD/F contaminated sediments at four target sites in the Tittabawassee River (MI) and at two less contaminated reference locations. Total TEQ concentrations were greatest in Megaloptera relative to all other orders of benthic invertebrates at target sites. Residues of total TEQ in Megaloptera were generally an order of magnitude greater at target sites (15.9 to 36.3 ng/kg) than at reference sites (0.61 to 4.5 ng/kg). Freeland Festival Park, a target site, had the most orders of benthic invertebrates sampled at one site. Comparatively, Megaloptera TEQ's were > Ephemeroptera > Odonata > Amphipoda > Trichoptera > Bivalvia > Gastropoda. Thus, it would appear that Megaloptera species may be useful for screening level dietary exposure assessments as a site-specific worst case benthic invertebrate.

TP230 (WIN-1116-605775) Risk Assessment of Mixtures of Alcohol Ethoxylates: 2. Fate and Bioavailability of AE-Homologues in Effluents of Waste Water Treatment Plants.
Start time: 8:00 AM
Wind, T¹, van Compernolle, R², Dorn, P², Eadsforth, C³, Toy, R³, Boeije, G⁴, Belanger, S⁵, Marshall, S⁶, Zeller, D⁷, ¹ Henkel KGaA, Duesseldorf, Germany² Shell Global Solutions, Houston, Texas, USA³ Shell Chemicals Ltd, London, United Kingdom⁴ Procter & Gamble Eurocorp, Brussels, Belgium⁵ Procter & Gamble, Cincinnati, Ohio, USA⁶ Unilever Colworth, Bedfordshire, United Kingdom⁷ BASF, Ludwigshafen, Germany
The exposure of aquatic organisms to alcohol ethoxylates (AE) is influenced by sorption to sewage solids and biodegradation in sewage treatment plants (STP) and subsequent adsorption/desorption to organic matter in surface waters. Environmental monitoring indicates that the distribution of AE-homologues in STP-effluents differs from the distribution in commercial AE products with a relative increase in the proportion of fatty alcohol (AOH=AE with zero ethoxylation). To determine the contribution of AE-derived AOH to the total concentration of AE and AOH in STP effluents, we conducted a laboratory continuous activated-sludge study (CAS). This consisted of a test unit fed with AE-amended synthetic sewage and a control unit fed with only synthetic sewage to avoid AE contamination from the feed. The removal efficiencies of some 114 AE-homologues were determined by application of a specific and sensitive analytical method. Sorption of AE ethoxymers to particulate matter is mainly a function of the chain length and the degree of ethoxylation of each homologue. In order to generate a quantitative structure activity relationship (QSAR) for the sorption of AE's in the aquatic environment, an experimental determination of sorption coefficients for a number of individual AE homologues and alcohols was undertaken. These data were compiled with literature data to cover a wide range of AE homologues. The extent of removal of AE ranged from 99.70% for C18-compounds to >99.98% for C12-16. Relatively high AOH concentrations were observed in the effluents from blank and test units indicating that only a small fraction of the AOH in STP-effluents originates from AE entering STPs. This information enables an estimation of the concentrations of AOH and AE resulting from the use and disposal of commercial AE. Regression analysis of the compiled sorption data suggests that one QSAR is sufficient to predict the bioavailability of all AE-homologues, including AOH, in surface waters.

TP231 (CAR-1117-751576) Differential toxicity of naphthoic acid isomers in medaka (Oryzias latipes) embryos using a 96-well plate format.
Start time: 8:00 AM
Carney, M¹, Kullman, S¹, Hinton, D¹, ¹ Duke University Nicolas School of the Environment and Earth Sciences, Durham, NC, USA
Polycyclic aromatic hydrocarbons (PAHs) are widespread pollutants found in soils, estuaries, and sediments that are metabolized in the environment. To address lack of toxicity data on PAH metabolites found in contaminated soils and sediments of Elizabeth River, VA we characterized the toxicity of 4 naphthoic acid structural isomers of hydroxy naphthoic acid: 1H2NA, 2H1NA, 2H3NA, and 6H2NA, which are bacterial metabolites of PAH compounds. Medaka fish (Oryzias latipes) embryos and larvae were used to determine early life stage toxicity. To establish a robust, statistically significant platform for assessment of early life stages we used a 96-well micro plate format. Results indicated that the four naphthoic acids show differential toxicity with 1H2NA, 2H1NA, and 2H3NA having more developmental toxicity, specifically circulation abnormalities including pericardial edema and tube heart. To identify mechanisms of toxicity we detected CYP1A time of expression and location in vivo. qPCR measured CYP1A induction was different between isomers dosed at respective concentrations affecting 50% of exposed individuals (EC50s). Results indicated that circulation abnormalities followed P450 induction and this response was consistent with PAHs toxicity. 96-well micro plates are suitable exposure chambers that provided statistically sound evaluations and efficient toxicity screens.

TP232 (BEL-1116-609083) Risk Assessment of Mixtures of Alcohol Ethoxylates: 3. Synthesis of Fate and Effects in Europe and North America.
Start time: 8:00 AM
Belanger, S¹, Boeije, G², Cano, M³, Dorn, P³, Eadsforth, C⁴, Federle, T¹, Gumbel, H⁵, Marshall, S⁶, Van Compernolle, R³, Wind, T⁷, ¹ Procter & Gamble Company, Cincinnati, OH, USA² Procter & Gamble Company, Brussels, Belgium³ Shell Global Solutions USA, Houston, TX, USA⁴ Shell Global Solutions UK, Chester, UK⁵ BASF, Ludwigshafen, Germany⁶ Unilever Research, Merseyside, UK⁷ Henkel KGaA, Dusseldorf, Germany
An alcohol ethoxylate (AE) environmental risk assessment integrated effluent monitoring, fate, and ecotoxicity research in a novel approach. This comprises a new application of mixture toxicity theory based on simple similar concentration addition of AE homologues in a species sensitivity distribution (SSD) context. AE chronic ecotoxicity (EC10) for 17 species in 60 individual tests on 25 different AE mixtures or pure materials was summarized. Test results on diverse AE structures were normalized to predict toxicity for pure homologues in a matrix that spanned alkyl chain lengths of 12 to 18 and ethoxylate chain lengths of 0 (alcohol) to 18. Normalization integrated several new quantitative structure activity relationships for algae, daphnids, fish, and mesocosms. Single-species data, normalized to fill the alkyl and ethoxylate chain length matrix, was ultimately summarized as SSD (HC5s) for all possible homologues. Exposure to AE was determined in municipal wastewater treatment plant effluents collected throughout Europe, Canada and the United States. The monitored treatment systems were primarily domestic with little industrial input and involved measurement of all AE homologues in the range described above. Correction of exposure to exclude fatty alcohol derived from sources other than AE and to account for non-bioavailable, sorbed homologues based on experimental evidence was used to determine AE concentrations in undiluted effluents. Effluent exposure and SSD results were integrated in a Toxic Unit (TU)-based model. In general, sites employing activated sludge treatment had lower TUs (lower risk potential) than those using fixed biofilm treatment processes. Summed TUs using the SSD and undiluted effluent fingerprints corrected for exposure, accounting for alcohol derived only from AE and for bioavailability due to sorption, ranged from 0.011-0.184. Hence, even in a worst-case undiluted situation, it is concluded that the potential risk caused by AE to the aquatic environments of Europe and North America is low (TU less than 1).

TP233 (SES-1118-291262) Assessment of belted kingfisher (Ceryle alcyon) dietary exposure to PCDDs and PCDFs in the Tittabawassee River, MI.
Start time: 8:00 AM
Seston, R¹, Zwiernik, M¹, Moore, J¹, Tazelaar, D¹, Wong, H¹, Bradley, P¹, Fredricks, T¹, Coefield, S¹, Jones, P¹, Giesy, J¹, ¹ Michigan State University, East Lansing, MI, USA
A site-specific dietary assessment of belted kingfishers residing in the Tittabawassee River floodplain was conducted. The target study area includes 38 km of the river from the upstream boundary at the city of Midland, MI to the confluence of the Tittabawassee and Shiawassee Rivers. Previous studies have shown that this section of the Tittabawassee River contains polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in soils, sediments, and biota. Mean PCDD/PCDF concentrations in soils and sediments downstream of Midland, MI were 10- to 20- fold greater than those collected upstream in a reference area. Dietary exposure was estimated using site-specific concentrations of representative dietary items, which were determined by both site-specific and literature-based dietary compositions. The site-specific dietary composition was determined through direct observation of dietary items fed to the nestlings, and prey remains collected from the nest. Concentrations of the seventeen 2,3,7,8 substituted PCDD/DFs were quantified in select dietary items and normalized to 2,3,7,8 dibenzo-p-dioxin using WHO avian TEFs. Total TEQs in prey items ranged from 3.5x10^-1-1.5 (n=3) and 1.2x10¹-4.0x10² (n=8) ng/kg, ww for crayfish upstream and downstream, respectively, and from 9.0x10^-1-9.1x10^-1 (n=2) and 1.3x10²-4.0x10² (n=4) ng/kg ww for forage fish (<25cm) upstream and downstream, respectively. Dietary exposure based on both literature and site-specific dietary compositions as well as resulting hazard quotients for belted kingfisher will be presented

TP235 (DOU-1116-522706) Surfactant Risk Assessment: What Is Going On?
Start time: 8:00 AM
Douben, P¹, Hager, C², Haux, C³, Klotz, H, Schowanek, D⁴, Schwarz, K⁵, Steber, J, Veenstra, G⁷, ¹ Unilever, Sharnbrook, Bedfordshire, United Kingdom² Sasol, Marl, Germany³ AkzoNobel, Stenungsund, Sweden⁴ Clariant, Frankfurt, Germany⁵ Proctor & Gamble, Strombeek-Bever, Belgium⁷ Henkel, Duesseldorf, Germany
Surfactants are widely used in large quantities in many consumer products as well as in products for professional or industrial use. Due to the nature of their use, most surfactants are discharged into the environment through sewage treatment plants (the majority), through septic tanks, or directly to the aquatic environment in situations where no treatment systems are available. ERASM, Environmental Risk Assessment and Management, an initiative between CESIO (The European Committee of Surfactants & their Organic Intermediates) and AISE (Association Internationale de la Savonnerie, de la Detergence & des Produits Entretien), was founded in 1991 with the specific objective of developing risk assessment methodology for surfactants. ERASM has a major programme of activities on surfactants including fate and effects in various environmental (sub-)compartments, such as levels and behaviour in sludge, the aquatic and marine environment, and sediments. Previous programmes have provided input to various regulatory developments such as the Detergents Regulation adopted in 2004. An overview will be given on the various experiences with surfactant risk assessments, their conclusions as well as on areas, where further research is required. The substantial efforts made by industry in understanding the interaction between its products and the environment will be highlighted.

TP236 (HUL-1117-200447) Sequential Assessment of Lines of Evidence (SALE): A Modified Weight of Evidence Approach for Ecological Risk Assessment.
Start time: 8:00 AM
Hull, R.¹, Swanson, S.², ¹ Cantox Environmental Inc, Mississauga, ON, Canada² Golder Associates, Calgary, AB, Canada
Weight of evidence approaches have been used in ecological risk assessment for many years. The approaches integrate various types of data (e.g., from chemistry, bioassay, and field studies) to make an overall conclusion of risk. However, many of these approaches have been qualitative and lacked transparency related to how each type of data (or line of evidence) was weighted or integrated into the overall weight of evidence conclusion. Therefore, a modified weight of evidence approach has been developed that should assist risk managers by allowing their decisions to be based on well-documented conclusions and recommendations. The first aspect of this modified approach that makes it unique is that the comparison of abiotic media concentrations to benchmarks, as well as direct food-chain modeling, are used to rule out risks; these modeled risks (e.g., hazard quotients or HQs) do not form part of the final weight of evidence analysis. Rather a sequential analysis of lines of evidence (SALE) is proposed. In the SALE approach, if HQs are less than 1 when conservative exposure conditions are assumed and sensitive effects endpoints are used, we can be confident that there will be no risks (especially when the models predict risks to individual receptors rather than to populations). For those receptors for which risks cannot be ruled out, additional lines of evidence must be considered. The process of working through the SALE approach includes the following: 1) scoring of lines of evidence relative to causal criteria; 2) evaluation of the magnitude of the observed response; and 3) an integration of the causal strength with the magnitude of response into a weight of evidence summary for each site or sub-area within the entire study area. Although only the theory of the SALE approach is presented in this poster, an aquatic ERA example is given in a companion poster by Swanson et al. for the Columbia River in British Columbia.

TP237 (OHL-1117-234815) Ecological Risk Assessment from Site Screening to Restoration of the Bolsa Chica Lowlands, California.
Start time: 8:00 AM
Ohlendorf, H.¹, Gorbics, C.², Eisert, M.¹, ¹ CH2M HILL, Sacramento, CA, USA² U.S. Fish and Wildlife Service, Carlsbad, CA, USA
The Bolsa Chica Lowlands in Orange County, CA, are being restored from an operating oil field to more favorable wildlife habitat, with a range of coastal tidal and non-tidal wetlands as mitigation for development of port facilities in nearby Los Angeles County. The site is large (about 485 hectares [1,200 acres]) and complex, with more than 430 active or abandoned oil wells, along with associated pipelines, roads, former tank farms, and other related facilities on the property. Storm drainage enters from nearby urbanized areas. Over 230 chemicals of potential concern were initially identified for the site. Our ecological risk assessment identified 70 chemicals that present risks to plants or animals that are expected to use the site after restoration. The Bolsa Chica Technical Committee was formed in 1997 to evaluate the risks and develop an approach to clean-up and restoration. Using a weight-of-evidence approach, the Technical Committee (which includes several federal and state agencies) developed clean-up criteria that focus on 14 of the risk-driver chemicals. Inclusion/exclusion of chemicals for cleanup was based on correlation with other analytes, detection frequency, co-location of exceedances of criteria, availability of toxicity values, and best professional judgment. Clean-up levels were identified for material to be managed on-site and material to be hauled off-site. In 2004, the U.S. Fish and Wildlife Service initiated the first construction phase of the Bolsa Chica Restoration Project.

TP238 (LUK-1117-814184) Evaluation of Non-Detects in Risk Assessment.
Start time: 8:00 AM
Luke, N.¹, Chen, G.¹, Olsen, M.¹, Kirchner, S.¹, Mayo, J.¹, ¹ CDM, Edison, NJ, USA
Analytical data generated from field samples may be below the detection limit of the analytical method. These data are usually described as non-detects and not reported as zero. The detection limit is usually reported as the non-detect result with a U data qualifier indicating that the result is unknown and below the specific detection limit of the analytical procedure. A commonly accepted practice in both human health and ecological risk assessments has been to use half of the detection limits for non-detects in the calculation of the concentration term. This approach assumes that the average value of non-detects could be as high as half the detection limit. However, when the non-detects are more than half of the analytical results for a chemical, using half the detection limit may produce biased high results. To improve the accuracy of the calculation of the concentration term when considering non-detects, statistical analyses have been recommended to evaluate the non-detects, especially when non-detects make up a large fraction of the data set. The complexity of statistical analysis is usually dependent on the amount of data below the detection limits. Various statistical methods for evaluating non-detects in the calculation of the concentration term were used to compare the differences in the computed concentrations of test data sets. The computed concentrations were used to determine to impacts on the risk calculations.