Validation of a Framework for Evaluating the Potential Effects and Risks of Trace Organic Compounds (TOrCs) to Aquatic Life

Transcription

1 Validation of a Framework for Evaluating the Potential Effects and Risks of Trace Organic Compounds (TOrCs) to Aquatic Life Brendan Cousino, LimnoTech Michigan Water Environment Association Wastewater Administrators Conference January 26, 2017 Frankenmuth, MI

2 Background Trace Organic Compounds (TOrCs) TOrCs enter wastewater from human wastes and domestic activities. Common Sources: Antioxidants, Detergents, Disinfectants, Dyes/Pigments, Fire Retardants, Flavors/ Fragrances, Fuels, Herbicides, Insecticides, Pharmaceuticals, Solvents Elevated fish intersex observed below WWTP outfalls Due to exposures to endocrine disrupting compounds (EDCs) (e.g. estrogen) Exposures occur simultaneously with many other stressors (e.g. nutrients, metals, pesticides, PAHs, TDS, temperature, altered habitat, flow) A complex puzzle Intersex sturgeon tissue - Diana Papoulias, USGS 2

3 USGS Sampling ( ) Sampling at 57 site around the Great Lakes 26 in Michigan Tested for 69 TOrCs 13 Classes of compounds 28 associated with human or aquatic toxicity 36 are known or suspected EDCs Water quality benchmarks for individual TOrCs were exceeded at 20 sites At 7 sites benchmarks were exceeded by a factor of 10 or more Medium to High risk of estrogenic effects at 10 sites Estrogenic compounds at 3 sites were comparable to values reported in effluent Urban-related land uses were significant predictors of TOrCs 3

4 USGS Sampling ( ) Figure SI-2. Summary map of potential for adverse biological effects from organic compounds in water samples by sampling location (from Baldwin, et al. 2016). 4

5 WE&RF s Research on TOrCs 3-Year Project for Water Environment & Reuse Foundation (WE&RF) CEC6R12: Testing and Refinement of the Trace Organics Screening Tool Refining and validating a screening tool developed in a 1st Phase of WERF research (2010) for evaluating the effects of trace organics (TOrCs) downstream of utilities. 5

6 WE&RF s Research on TOrCs Research Areas Treatability Aquatic Ecological Effects Risk Communications Project Summary 50 TOrC-related funded projects Objective Help facility and industry managers make decisions t_a_glance.aspx 6

7 WE&RF Project CEC6R12: Testing and Refining Site Screening Tools (Phase 2) Vision for Screening Tools Must be useful and usable by utilities Good fit for existing utility data Easy to interpret results Support sound decisions by utilities Targeted data gathering Effective source control and treatment Promote clearer understanding of complex issues Assist communication with stakeholders & regulators 7

8 Three Step Framework for Screening Sites for Potential TOrC Risk 1. Determine if biological community is impaired 2. Use existing data to construct lines of evidence for an overall weight-ofevidence assessment of the role of TOrCs in impairment (Level 1 WoE) 3. If warranted, design and conduct a sampling program to generate contemporary datasets for a more detailed weight-of-evidence assessment (Level 2 WoE) 1. Assess biological community 2. Qualitative WoE (Existing Data) 3. Semi-Quantitative WoE (New Data) 8

9 First Level of Screening: Basic Weight of Evidence Use existing site data to: Characterize level of impairment Evaluate the roles of TOrCs and other stressors Assign site to a risk level: So management response can be consistent with risk Accounting for uncertainty Applied to five case study sites with resulting potential risk level including Moderate and Possible Concern 9

10 Tools to Assist Use of the Site Screening Risk Framework Smaller, cost-effective list of TOrCs to monitor Suggested list of biomarkers to evaluate TOrC effects Risk Calculator model comparing TOrC exposures to TOrC effect levels Level 1 WoE site screening assessment and scoring tool Level 2 WoE scoring examples 10

11 WERF Indicator TOrCs No Compound CAS # TOrC Class High Priority Recommended Indicator TOrCs (use all compounds in assessments and as many as possible in monitoring) Treatability Indicator Ubiquitous Presence/ Absence Indicator 1 N,N-diethyltoluamide (DEET) Personal care product Y Y 2 Triclosan Personal care product Y Y Y Y 3 Carbamazepine Pharmaceutical Y Y Y 4 Fluoxetine Pharmaceutical Y Y Y 5 Gemfibrozil Pharmaceutical Y Y Y 6 Ibuprofen Pharmaceutical Y Y Y 7 Meprobamate Pharmaceutical Y Y Y 8 Sulfamethoxazole Pharmaceutical Y Y Y 9 Trimethoprim Pharmaceutical Y Y Y 10 Bisphenol A Other Y Y Y Y 11 Caffeine Other Y Y Y 12 Androstenedione Hormone Y NA Y 13 17β-Estradiol (E2) Hormone Y NA Y 14 Estrone Hormone Y Y NA Y Nonpoint Source Indicator TOrCs (select 1-2 compounds for assessment and monitoring) 15 Fluoranthene PAH Y NA Y 16 Atrazine Pesticide NA 17 Bifenthrin Pesticide Y a NA 18 Chlorpyrifos Pesticide Y NA Y 19 Pentachlorophenol Pesticide Y NA 11

12 TOrC Risk Calculator Predicts the risk of effluent TOrCs in receiving waters to aquatic life Exposure based on either measured or predicted effluent TOrC concentrations and in-stream dilution Effects based on either laboratory measured or QSAR predicted acute and chronic toxicity Already tabulated in Risk Calculator Risk based on comparing the Predicted Exposure Concentration (PEC) to the Predicted No Effect Concentration (PNEC) using Risk Quotient (RQ) method RQ = [PEC]/[PNEC] RQ > 1 indicates potential risk Benefits Site specific model Easy to use for utility staff Requires only data for a single site Easily updated with new information/data 12

13 Risk Calculator Example PNEC RQ = PEC / PNEC = / 0.02 PEC 13

14 Case Study Example, Level 1 Weight of Evidence Tier of Concern: Moderate Concern 14

15 Level One WoE Scoring (Qualitative) Level 1 WoE Element High WoE Factor Score Moderate WoE Factor Score Possible WoE Factor Score Low WoE Factor Score TOrC Effects Multiple surveys show biomarker or other effects Individual survey shows biomarker or other effects Evidence of physical deformities, tumors, and lesions Individual survey shows NO biomarker or other effects TOrC Exposure Risk quotient for more than one indicator compound is greater than 1 using site-specific measured effluent data and 7Q10 flow Risk quotient for one indicator compound is greater than 1 using site-specific measured effluent data and 7Q10 flow Risk quotient for one indicator compound is greater than 1 using literature effluent data and 7Q10 flow Risk quotient for all indicator compounds is less than 1 using measured or literature effluent data and 7Q10 flow TOrC Site Factors Other Stressors Effluent discharge comprises more than 70% of the total stream flow, OR WRRF level of treatment is Primary, OR Treatment effectiveness is poor, based on sludge residence time and effluent concentrations of TSS, BOD and NH3 Habitat is adversely impacted, OR DO exceeds WQS, OR NH3 exceeds WQS, OR at least 3 parameters are identified as potential stressors Effluent discharge comprises between 1% and 70% of the total stream flow, OR WRRF level of treatment is Secondary or Advanced Secondary, OR Treatment effectiveness is moderate, OR At least half of the other risk factors score High At least 2 parameters are identified as potential stressors Incomplete data One parameter is identified as potential stressor Effluent discharge comprises less than 1% of the total stream flow, OR WRRF level of treatment is Tertiary, OR Treatment effectiveness is good, OR At least half of the other risk factors score Moderate or Low No parameters are identified as potential stressors 15

16 Second Level of Analysis: More Complete Weight of Evidence Where screening indicates at least a Moderate Level of Concern: Fill in gaps in site chemistry/community/habitat data Additional biomonitoring, upstream and downstream Characterize relationships between TOrCs, other stressors, and aquatic life impairment Two case study sites where initial screening indicated Moderate or Possible Level of Concern Validate tools and Level 1 WoE results Advance science of TOrC-related biomarker analysis 16

17 Sampling to Support Multiple Lines of Evidence Chemical loadings (in-stream, WWTP) TOrCs Conventional: nutrients, metals, solids, BOD5, alkalinity, hardness Exposure effects Caged minnows In-situ caged invertebrates In situ toxicity identification evaluation Biological community assessments Stream physical conditions Habitat Dissolved oxygen, temperature, ph, conductivity via sonde Flow (in-stream and at WWTP) 17

18 TOrC Exposure Levels and Potential Risk Exposure: Total TOrC levels consistent with effects data Potential Risk Estimated Risk Quotient (RQ) as PEC/PNEC for indicator TOrCs. RQ >1 identified as potential risk Site 1: 1/10 indicator TOrCs have RQ > 1 Site 2: 0/10 indicator TOrCs have RQ > 1 Results consistent with effects and exposure data 25 compounds analyzed by EPA-Cincinnati Bold compounds = Indicator TOrC TorC Compound Cas No. 4-Nonylphenol Androstenedione (ADS) Atrazine Bisphenol A Caffeine (CFN) Carbamazepine (CBZ) Dihydrotestosterone DNORG (17-Desacetyl Norgestimate) DROS (Drospirenone) EDA (Ethynodiol Diacetate) Estradiol (E2) Estriol Estrone (E1) Ethinyl estradiol (EE2) Levonorgestrel Medroxyprogesterone Acetate MEGA (Megestrol Acetate) Nonylphenol Diethoxylate Nonylphenol Mono Ethoxylate Norethindrone NORG (Norgestimate) Progesterone Testosterone (TST) Triclocarban Triclosan (TCC)

19 Vtg in Liver Samples from Fathead Minnow Males - qpcr Site 1 Site 2 Biales, et al Environ. Toxicol. Chem. 26:

20 Vtg in Plasma Samples from Fathead Minnow Males-ELISA Site 1 Site 2 Statistically significant differences but measured concentrations are close to or below detection limits Statistically significant differences but measured concentrations are close to or below detection limits US Environmental Protection Agency, EPA/600/R-01/067. Duluth, MN 20

21 Level 2 Weight-of-Evidence Approach and Results Approach Compare downstream to upstream Semi-quantitative scoring using minus signs correlated to: Low effect (0) Possible effect (- -) Moderate effect (-) High effect (- - -) Overall Level of TOrC concern determined Intended as examples that can be adjusted for site-specific conditions Results Level of TOrC Concern 1 Biological Indices TOrC Exposure 21 TOrC Effects Other Stressors Site 1 Low Site 2 Possible Conclusions Impacted stream likely due to non-torc stressors. Continued monitoring suggested Potential wastewater effluent effects. Continued monitoring with special studies suggested

22 Conclusions Assessment Framework Set of useful tools, within logical risk-based framework Adaptable to site-specific considerations Requires regulatory driver: biological impairment Recognizes potentially confounding role of non-torc stressors WoE consistent with evolving science Tools/protocols are Flexible enough to begin with available data Iterative, for smart data gathering and reduction in key uncertainties Holistic, recognizing potential effects of other stressors on health of aquatic ecosystem Designed to be easy for wastewater utilities to use 22

23 Questions Brendan Cousino LimnoTech (734) Acknowledgements: Lola Olabode, Program Director WE&RF Carrie Turner, John Wolfe and Jen Daley, LimnoTech Allen Burton, University of Michigan Drew McAvoy, University of Cincinnati 23