Mark Harris June 22, th Passaic River Symposium Montclair, NJ

Transcription

1 Mark Harris June 22, th Passaic River Symposium Montclair, NJ

2 LPR Human Health Risk Assessment (HHRA)* Objectives: 1. Determine the current cancer/non-cancer human health risks from ingestion of fish from LPR River Miles (RMs) 1-7 using: a. Publically-available fish tissue database b. Data from a site-specific creel angler survey (CAS) c. Deterministic and probabilistic risk analyses d. Relative potency (REP) distributions for dioxin-like compounds (DLCs) 2. Evaluate HHRA underpinnings of the Focused Feasibility Study (FFS) *Urban JD, TachovskyJA, Haws LC, WikoffStaskalD, and Harris MA (2009). Assessment of humanhealth risks posed by consumption of fish from the Lower Passaic River, New Jersey. Sci Total Environ. 408: *TachovskyJA, Urban JD, StaskalWikoffD, Haws LC, and Harris MA (2010). Reduction of a large fish tissue analytedatabase: Identifying and assessing data specific to a remediation site for risk assessment application. Chemosphere. (Epub June 4, 2010).

3 LPR HHRA: Resources Creel Angler Survey Data Ourpassaic Database 3

4 LPR HHRA: Fish tissue data Representative Fish (RF) Utilized CAS consumption data to weight the contributions of fish species to ingestion and analyte concentrations. Parameter represents the concentrations of various analytes in all fish species. Fish consumption in LPR RMs 1-7: White perch (RF = 55%) Common carp (RF = 23%) Striped bass (RF = 10%) American eel (RF = 8%) 4 Brown bullhead catfish (RF = 4%)

5 LPR HHRA: Approach D A T A R E D U C T I O N P R O C E S S Characterize Concentrations of Analytes in LPR Representative Fish A N A L Y T E S 156 R I S K A S S E S S M E N T Identify analytes with toxicological factors (Cancer and/or Non-cancer) HHRA Phase Deterministic Probabilistic Identify Risk Drivers* HHRA Phase 2: Probabilistic Total PCBs, PCDDs, PCDFs, DL-PCBs 5 *Theseaccounted for >70% of human health risk

6 LPR HHRA: Exposure Assumptions Parameter Fish ingestion rate (g/day) Crab ingestion rate (g/day) Analyte concentration Information used in Urban et al. (2009) LPR Risk Assessment Deterministic: Central Tendency (CT) 0.42, Reasonable maximum exposure (RME) 1.8 Probabilistic: gamma distribution based on CAS Not applied: The CAS found crab was used only as bait and not consumed. Phase 1: CT 50 th percentile, RME 95 th percentile Phase 2: distribution of each chemical in each fish species Exposure Frequency (days/year) 365 Exposure Duration (years) Deterministic: CT 1.5, RME 4.8 Probabilistic: gamma distribution of CAS Receptor Body Weights (kg) Deterministic: 71.8, 15 Probabilistic: normal distribution of USEPA EFH values Non-cancer Averaging Time (days) Cooking loss (fraction) DLC Cancer Toxic Equivalency Deterministic: CT 365 days x 1.5 years (child & adult); RME 365 days x 4.8 years (child & adult) Phase 1: not applied Phase 2: normal distribution of USEPA EFH values Deterministic: WHO 2006 TEFs Probabilistic: WHO 2006 TEFs and weighted REPs 6

7 Phase 1 Risk Estimate Comparisons: Other Chemical Groups PCDD/Fs, DL- & non-dl PCBs Metals Organics PAHs 100% 90% Percentage of Total Cancer Risk 80% 70% 60% 50% 40% 30% 20% 10% 0% CT CT RME RME CT CT RME RME CT CT RME RME Deterministic Analysis WHO TEF Probabilistic Analysis Weighted REP Probabilistic Analysis 7

8 Phase 2: Cancer Risk Estimates Total PCDD/F/PCBs (2006 WHO TEFs) (weighted REPs) Mean 1.60E E-06 50% 4.70E E-07 95% 6.70E E-05 (2006 WHO TEFs) (weighted REPs) Mean 7.30E E-05 50% 2.20E E-06 95% 3.10E E-05 * Total risk derived by weighted REPs X greater than WHO TEF risks. 8

9 Phase 2: Cancer Risk Estimates* 2006 WHO TEFs PCDD/Fs DL-PCBs non-dl PCBs Mean 8.6E E E-07 50% 2.2E E E-08 95% 3.8E E E-06 PCDD/Fs DL-PCBs non-dl PCBs Mean 4.0E E E-06 50% 1.1E E E-07 95% 1.7E E E-06 Weighted REPs PCDD/Fs DL-PCBs non-dl PCBs Mean 8.6E E E-07 50% 2.2E E E-08 95% 3.7E E E-06 PCDD/Fs DL-PCBs non-dl PCBs Mean 4.0E E E-06 50% 1.0E E E-07 95% 1.7E E E-06 9 * For DL-PCBs, risks derived with weighted REPs are 8 X greater than WHO TEF risks, driven by mono-ortho PCB TEF variability.

10 Phase 2: Non-cancer Results (Hazard)* Mean % % = Hazard Index > 1.0 * For non-dioxin-like PCBs only. 10

11 Perspective: DLC Dose from Breast Milk and Diet 1000 Estimated Dose [pg TEQ/kg-day (log)] WHO Tolerable Daily Intake 0 Birth th 95 th 50 th 95 th mean Infant age (months) Breastfeeding* (percentile) (percentile) LPR Fish Consumption / Typical Diet ] ] Receptor Consumption Pathway 11 *LorberM, Phillips L (2002). Infant exposure to dioxin-like compounds in breast milk. Environ Health Perspect. 110(6):A LorberM, Patterson DG, HuweJ, Needham LL (2008). Evidence for a decline in background exposure of Americans to dioxins from the 1990s to the 2000s. OrganohalogCompd. 70:

12 Perspective: Adding to Background Cancer Risk U.S. Background Lifetime Cancer Risk = 41% (0.41)* LPR Fish Ingestion Excess Cancer Risk = 8.8 x 10-5 ( ) + = Result: adding nine one hundred-thousandths excess cancer risk to an overall U.S. background cancer risk of four-tenths. *National Cancer Institute. SEER Cancer Statistics Review Lifetime Risk (Percent) of Being Diagnosed with Cancer by Site and Race/Ethnicity Both Sexes, 17 SEER Areas, As reported in the President s Cancer Panel s Annual Report 12 LPR HHRA Phase 2: Total Probabilistic excess cancer risk for 95th percentile child, (weighted REPs) Report.

13 LPR HHRA: Strengths & Uncertainties Strengths: Refined - parameter distributions rather than point estimates Utilizes peer-reviewed site-specific fish ingestion data Consistent with USEPA risk assessment guidelines Remaining Uncertainties: Fish tissues samples were collected between Fish advisory effect on fishing habits Future potential exposures Future EPA guidance on risk assessment 13

14 LPR HHRA: Conclusions Phase II Chemicals of Concern: Cancer Risk PCDD/Fs and PCBs (DL-PCBs and non-dl-pcbs) each responsible for approximately half. Non-cancer Hazard PCBs comprise most of the calculable analyte hazard. Risk & Hazard Estimates: Refined PCDD/PCDF/PCB cancer risk are within acceptable range ( ) Hazard estimates slightly exceed 1.0 (child, 95 th percentile) Bottom line: Under current conditions, 1. ingestion of fish does not present an unacceptable health risk to the LPR angler population, and 2. human health risk estimates do not support FFS conclusions. 14

15 Acknowledgements ToxStrategies Team Jon Urban Andrew Tachovsky Daniele Staskal Laurie Haws Alexis Sheehy Tierra Solutions provided funding for preparation of this risk assessment 15