ESM 223Ecological Risk AssessmentEcological Risk AssessmentProcess to evaluate likelihood of adverse ecological effects as result of exposure to one or more stressorsFunction of ERAdocument whether actual or potential ecological risk exists at a sitescreen contaminants present at a site for those that pose an ecological riskgenerate information to evaluate optionsHow is ERA regulated? Part of RCRA and CERCLA set standards, take action Strengthened by SARA cleanup levels and remedial alternatives National Contingency Plan (NCP) implementation of CERCLA & SARA regulations remediation goals based on applicable or relevant and appropriate requirements (ARAR) Directed by regulatory and resource agencies USEPA Dept of Toxic Substances Control Regional Water Quality BoardUSEPA’s Responsibilities Section 404 of Clean Water Act Federal Water Quality Control Act Clean Air Act Toxic Substances Control Act Federal Insecticide, Fungicide and Rodenticide Act Endangered Species Act Section 662(a) and 2903 of Fish & Wildlife Conservation Act Coastal Zone Management Act Section 2171 of Wild and Scenic Rivers Act Migratory Bird Treaty ActSteps in ERA ProcessProblem Formulationassessment endpointsconceptual model(s)analysis planAnalysisEcological Exposure and EffectsRisk CharacterizationEstimation and descriptionRisk ManagementDecision makingScreening Level Risk AssessmentSimplified risk assessmentsMake rapid decisions early in the processDivide sites intoSites that present significant immediate ecological risk and require early remedial actionSites with no ecological risk, requiring no further actionSites that require further studyScreening ERAFor the screening levelAssessment endpoints must be explicitMeasurable endpoints must be a measurable ecological characteristic - related to assessment endpoint Determine whether exposure is or may be above the levels where adverse ecological effects might be expectedEstablish exposure pathways of concernTools in an ERAEnvironmental ChemistryDetermine contaminant fate and transportLiterature-based ecotoxicological data NOAELLOAELEcotox information sourcesAQUIRE DatabasePHYTOTOX DatabaseIntegrated Risk Information System (IRIS)Hazardous Substances DatabankUS FWS Contaminant Hazard ReviewATSDR Toxicological ProfilesRegistry of Toxic Effects of Chemical Substances (RTECS)Screening Criteria Water USEPA Ambient Water Quality Criteria Water Quality Objectives (CRWQCB, 1986) Sediments Sediments Effects Range Data from NOOA (Long & Morgan, 1991) Sediment Quality Objectives (CRWQCB, 1986) Washington State Marine Sediments Criteria (WDOE, 1991) Soils Quebec Soil Clean-up Criteria (QME, 1988) Dutch Soil Clean-up Act (Beyer, 1990) Criteria for Contaminated Soil/Sediment Cleanup (Fitchko, 1989)ERA ExampleNAWS at Point MuguEffects of sediment contamination on organisms near the baseCopper and PCBs are the main concern in this regionCopper can be acutely or chronically toxic to various organismsPCBs bioaccumulate and bioconcentrate, producing reproductive impairmentFox River Case StudyFox River Human Health and Ecological Risk AssessmentExecutive SummaryTable of ContentsGeographical SettingDetails of ERAFox River Case StudyHighlights of Executive SummaryPopulations consideredRecreational anglersSubsistence anglersHuntersDrinking water usersLocal residentsRecreational water usersConstruction workersFox River Case StudyHighlights of Executive SummaryFish contain PCBsAnglers can have Cancer Risks (CR) up to 1.5 x 10-3Hazard Index up to 56Based on Fish Tissue data from 1990 (study conducted in 1999)Fox River Case StudyHighlights of Executive SummaryPotential population exposedUp to 47,000 recreational anglersAbout 2-5,000 subsistence anglersCancer risk about the same in the four reaches consideredHighest risk from carp, followed by perch, walleye and white bassFox River Case StudyHighlights of Executive SummaryRisk to hunters ~ 10-4(PCB contaminated waterfowl)Risk to people drinking contaminated water ~10-6 in most contaminated stretch – mostly from arsenic in waterMay require further sampling to determine if arsenic continues to be a concernThis water is not directly used a drinking sourceFox River Case StudySourcesFox River Case StudyFox River Case StudyFox River Case StudyPollutant loading has decreased by 85% since 1970sAlthough PCBs not discharged directly, estimated loading of 3-5 kg/year from landfills and other sources (very low concentrations)Non-point sources: eroded particles and contaminated sediments from small creeksFox River Case StudyTransport ProcessesAtmospheric transport: contributes 2-16 kg PCB/yr to Green Bay in snow and rain plus some dry depositionSediment transport: primary mechanism for moving PCBs through the watershed and riverFox River contributes > 90% of PCB loading to Green BayConcentrations in water ~50-100 ng/LFox River Case StudySediment concentrations (from 532 samples!) range from 2 to 222 x 103µg/kgIn Sediment Deposits A, C and POG, total PCB loading exceeds 50 x 103µg/kgReflect specific point sources discharging PCBs in this regionFox River Case StudyPCBs in fish tissue have been as high as 26 x 103µg/kg tissue in carp (in 1976)Have generally dropped about an order of magnitude in more recent samplesTissues also contain dioxins, furans, pesticides (DDT, DDE, Dieldrin), mercury, lead and arsenic …See Figures 2.1 to 2.20 in reportFox River Case StudyWhere does data come from for risk assessment?Fox River Case StudyHuman Health Risk AnalysisFox River Case StudyFox River Case StudyFox River Case StudyEcological Risk AnalysisFox River Case StudyFox River Case StudyFox River Case StudyFox River Case StudyFox River Case StudyFox River Case StudyFox River Case