Seafood Safe
Case Study:
Voluntary Seafood Contaminant Testing and Labeling Program
EcoFish as First Adopter:
Nationwide Sustainable Seafood Distributor: •1500 Grocery Stores •125 Restaurants
Evolution:
• Media Attention • Consumer Demographics • Project Research
Conflicting & Confusing Messages:
“Sound's Salmon Carry High PCB Levels: But State Says Health Benefits of Eating the Fish Outweigh Risks”
“Mercury Debate Gets Murkier – No Clear Choices on Which Fish are Best” “Rich Folks Eating Fish Feed on Mercury too – “Healthy Diet” Clearly Isn’t”
“Study Finds Mercury Levels in Fish Exceed U.S. Standards” “E.P.A. Says Mercury Taints Fish Across U.S.” “E.P.A. Raises Estimate of Babies Affected by Mercury Exposure”
Consumers are Confused:
Something Fishy: The Salmon Debate The Miami Herald November 4, 2004
“Eat salmon, we're urged. It is rich in omega-3 fatty acids, which help our hearts, cholesterol and blood pressure, fights rheumatoid arthritis, and might even ease depression. Eat salmon only sparingly, we're warned. The fish, especially when farm-raised -- as is 65 percent of the salmon sold in U.S. supermarkets -- contains PCBs and other toxins that may cause cancer. What's a health-conscious consumer to do? Studies and counterstudies, alarms and assurances, leave the public unsure, anxious. “
Business Model:
• Autonomous Independent Structure
– – – – Advisory Panel Sampling Labs (Axys Analytical, Brooks Rand) Consumer Advocacy Organization (Environmental Defense)
• Precautionary Principle • EcoFish First Adopter
Marketing Strategy:
• • • • Positive Industry Message Consumer Driven State Agency Driven (CA A.G.) Media Follow Through
Future Financial Model:
• Industry Pays • Consultation w/ Client • Customized Programs:
– Species Life History, Regionality, Size Range, Seasonality, Historical Data, Etc.
• Testing • Licensing
Future Participation:
• Seafood Industry (Fisheries, Processors, Distributors, Packers) • Grocery Store Chains • Restaurant Chains
EcoFish Species Tested:
Wild Alaskan Salmon – Oncorhynchus keta Wild Alaskan Halibut – Hippoglossus stenolepsis Wild Peruvian Mahimahi – Coryphaena hippurus Wild Oregon/Washington Albacore Tuna – Thunnus alalunga • Wild California Squid – Loligo opalescens • Farmed Chinese Bay Scallops – Argopecten irradians • Farmed Florida White Shrimp – Penaeus vannamei • • • •
Contaminants Tested:
• Mercury • PCB‟s • Additional Future Contaminants?
Labeling:
• How to Read • Guidance Derivation
– EPA's Guidance for Assessing Chemical Contaminant Data for Use in Fish Advisories – EPA‟s Risk-Based Consumption Tables
Recommendations:
Label in Use:
4 fin-fish species (n=7)
3 shellfish species (n=3)
Thaw, homogenize & Sub-sample
Thaw, homogenize & Sub-sample
To Brooks Rand for Hg
Sub-sample extraction & clean-up
Sub-sample extraction & clean-up
7 Extracts:
Analyzed by
1 Extract:
Analyzed by
3 Extracts:
Analyzed by
1 Extract:
Analyzed by
LR GC-MS
HR GC-MS
LR GC-MS
HR GC-MS
Frozen samples received, homogenized & sampled at:
AXYS Analytical Services Ltd., Sidney, B.C., Canada
Results: HR vs. LR Comparability
• PCB concentrations presented as sum of individual congeners measured (HR=209; LR=18) • Detection limit differed by three orders of magnitude between LR & HR (0.1 ng/g versus 0.1 pg/g) • No congeners reported >0.1 ng/g via HR were absent from the targeted LR analysis • <0.10 ng/g = „0‟ for PCB congener summing purposes
Seafood PCB (ng/g, ww) by HR & LR GC-MS
Total HR PCB (Total of 209 congeners, ng/g) Albacore Tuna 6.60 Range Total LR PCB (Total of 18 congeners ng/g) 4.0 – 7.5 Ratio of LR PCBs to Total HR PCBs
Mahi Mahi Halibut
Keta Salmon Calamari White Shrimp Scallop
0.10 0.91
1.48 1.50 1.20 0.20
<0.10 - <0.10 0.10 – 0.43
<0.10 – 0.95 0.76 – 0.90 0.76 – 0.78 <0.10 - <0.10
Seafood PCB (ng/g, ww) by HR & LR GC-MS
Total HR PCB (Total of 209 congeners, ng/g) Albacore Tuna Mahi Mahi Halibut Keta Salmon Calamari White Shrimp Scallop 6.60 0.10 0.91 1.48 1.50 1.20 0.20 Total LR PCB (Total of 18 congeners ng/g) 4.80 <0.10 (0) 0.43 0. 51 0.89 0.78 <0.10 (0) Ratio of LR PCBs to Total HR PCBs 0.72 0 0.47 0.34 0.60 0.65 0
Conclusions
• Highest [PCB] in Albacore Tuna; lowest in Mahi Mahi. • [PCB]HR > [PCB]LR in all species. • Ratio of [PCB]HR: [PCB]LR was variable & generally increased with increasing total PCB concentrations. • “Short” LR PCB target list included all congeners > 0.1ng/g by HR. • HR data provides more reliable Total PCB estimate than LR. (LR estimate may provide a contingency estimate approach for decision purposes, e.g. by doubling total LR values).
4 fin-fish species (n=7)
3 shellfish species (n=3)
Thaw, homogenize & Sub-sample
Thaw, homogenize & Sub-sample
From Axys Analytical Services
Sub-sample
Sub-sample
Total Hg
by CVAFS
Methyl Hg
by CVAFS
Total Hg
by CVAFS
Methyl Hg
by CVAFS
(n=7)
(n=3)
(n=3)
(n=1)
Methodology: Total Hg and Methyl Hg
Total Hg – Appendix to EPA 1631 • HNO3/H2SO4/BrCl digestion & oxidation • SnCl2 reduction, purge & gold amalgamation • Cold Vapor Atomic Fluorescence Spectrometry (CVAFS)
Methyl Hg – EPA 1630 Modified • KOH/Methanol digestion • Ethylation, purge and trap, GC, pyrolysis • CVAFS
Quality Assurance
Total Hg • CRM average recovery 101.7%, RSD 7.6% (n=6) • MS/MSD average recovery 101.5%, RSD 7.8% (n=10) • MDL 0.07 ng/g Methyl Hg • CRM average recovery 111% (n=2) • MS/MSD average recovery 105% (n=2) • MDL 1.5 ng/g
Seafood Hg (ng/g, ww) by CVAFS
Total Hg (ng/g) Methyl Hg (ng/g) Mean Ratio of Methyl Hg to Total Hg
Albacore Tuna Mahi Mahi Halibut Keta Salmon Calamari White Shrimp Scallop
226-275 (249) 98.4-538 (223) 82.7-233 (169) 21.2-37.1 (28.4) 21.5-23.7 (22.3) 5.47-11.0 (6.49) 8.45-9.35 (8.79)
214-258 102-595 86.3-284 20.5-30.0 23.1 5.67 7.38
95.1% 110.1% 110.9% 90.7% 97.5% 51.5% 78.9%
* (bracketed value) = mean
Conclusions
• Highest [Hg] in Albacore Tuna and Mahi Mahi; lowest in Keta Salmon • Albacore Tuna very consistent (RSD 6.7%) • Mahi Mahi and Halibut much more variable (wider range of fish size and age) • Methyl Hg = Total Hg in all Finfish species. • All shellfish low in Hg • Methyl Hg 50-100% of total Hg in shellfish