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PUBLIC HEALTH ASSESSMENT

LOWER DUWAMISH WATERWAY
SEATTLE, KING COUNTY, WASHINGTON


APPENDIX F: CONTAMINANT SCREENING PROCESS

The information in this section lays out how the contaminants of concern were chosen from a large set of different contaminants in fish/shellfish and sediment. In general, a contaminant's maximum fish concentration or 95th percentile sediment concentration is compared to a screening value (comparison value), and if the contaminant's concentration is greater than that value, then it is considered further. The health comparison values used in this public health assessment include screening values in fish from EPA guidance, environmental media evaluation guides (EMEGs), cancer risk evaluation guides (CREGs), reference dose media evaluation guides (RMEGs), EPA Region IX Preliminary Remedial Goals (PRGs), and Model Toxics Control Act (MTCA) cleanup values for soil.

EMEGs are calculated from ATSDR chronic Minimum Risk Levels (MRLs) using exposure parameters such as ingestion rate and body weight. EMEGs currently exist only for soil, water, and air. The MRL represents an estimate of daily human exposure to a contaminant below which noncancer adverse health effects are unlikely to occur. Comparison values were calculated using chronic Reference Doses (RfDs) for chemicals that did not have chronic MRLs. These values are called Reference Media Evaluation Guide (RMEGs). RfDs represent an estimate of daily human exposure to a contaminant below which non-cancer adverse health effects are unlikely. PRGs and MTCA cleanup values are determined using a similar methodology. Cancer Risk Evaluation Guides (CREGs) are estimated contaminant concentrations based on the probability that 1 additional cancer case may occur in excess of the number that will be expected to occur among 1 million people (assuming they have been exposed to the contaminant for a lifetime).

EPA's "Guidance for Assessing Chemical Contaminant Data for Use in Fish Advisories" suggests screening values to use when evaluating contaminant data in fish from water bodies where subsistence fishers consume fish. These values are calculated assuming a fish consumption rate of 142.4 g/day, a body weight of 70 kg, and a 70 year lifetime. Values were calculated using the most current oral RfD's and cancer potency factors in EPA's IRIS database. For contaminants that did not have recommended screening values listed by EPA, a similar methodology was used to derive screening values using MRLs and RfDs and CSFs (see equations below ). This screening method ensured consideration of contaminants that may be of concern for fish consumers, especially higher consumption groups such as tribal and API populations. The equations below show how comparison values were calculated for both noncancer and cancer endpoints associated with consumption of fish. A complete list of contaminants in fish/shellfish and sediment and their respective comparison valuesare provided in this Appendix.

mathematical equations

Table F1. Parameters used to calculate comparison values used in the fish contaminant screening process. Lower Duwamish Waterway, Seattle, King County, Washington
Abbreviation Parameter Units Value Comments
CV Comparison Value mg/kg Calculated  
RfD Reference Dose mg/kg-day Chemical Specific EPA
MRL Minimal Risk Level mg/kg-day Chemical Specific ATSDR
BW Body Weight kg 60 Female body weight
FIR Fish Ingestion Rate g/day 142.4 EPA
CF Conversion Factor kg/g 0.001 kilograms per gram
CPF Cancer Potency Factor kg-day/mg Chemical Specific EPA

Fish contaminant screening process for Lower Duwamish Waterway fish, Seattle, Washington
Figure F1. Fish contaminant screening process for Lower Duwamish Waterway fish, Seattle, Washington

Sediment contaminant screening process for Lower Duwamish Waterway fish, Seattle, Washington
Figure F1. Sediment contaminant screening process for Lower Duwamish Waterway fish, Seattle, Washington

Table F2. Frequency of detection for contaminants with screening values in Lower Duwamish Waterway Fish Seattle, Washington

Frequency of detection for contaminants with screening values in Lower Duwamish Waterway Fish Seattle, Washington

 

Frequency Detected : Number of Analyses

Contaminant Coho Chinook English Sole Mussels Striped Perch Dungeness Crab Rock Crab Quillback Rockfish
1,2,4-Trichlorobenzene 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
1,2-Dichlorobenzene 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
1,2-Diphenylhydrazine 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
1,4-Dichlorobenzene 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
2,4,5-Trichlorophenol 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
2,4,6-Trichlorophenol 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
2,4-Dichlorophenol 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
2,4-Dimethylphenol 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
2,4-Dinitrophenol 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
2,4-Dinitrotoluene 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
2,6-Dinitrotoluene 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
2-Chloronaphthalene 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
2-Chlorophenol 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
3,3'-Dichlorobenzidine 0:0 0:0 0:3 0:62 0:0 0:2 0:0 0:0
4,4'-DDD 40:70 79:83 9:9 0:27 0:0 0:0 0:0 0:9
4,4'-DDE 70:70 83:83 7:9 0:27 0:0 0:0 0:0 0:1
4,4'-DDT 7:68 55:83 0:9 0:27 0:0 0:0 0:0 2:6
4,6-Dinitro-o-cresol 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
4-Chloroaniline 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
Acenaphthene 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
Aldrin 0:57 0:83 0:9 0:27 0:0 0:0 0:0 0:0
Aniline 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
Anthracene 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
Antimony 0:0 0:0 0:3 0:62 0:0 0:2 0:0 0:0
Aroclor-1254 47:47 72:72 30:30 33:60 11:11 3:3 9:9 5:5
Arsenic 18:18 18:18 9:9 63:63 0:0 2:2 0:0 0:0
Benzidine 0:0 0:0 0:3 0:62 0:0 0:2 0:0 0:0
Benzo(a)pyrene TEQ 0:16 0:19 0:6 31:62 0:0 0:2 0:0 0:0

Benzo(a)pyrene

0:16 0:19 0:6 0:62 0:0 0:2 0:0 0:0
Benz(a)anthracene 0:16 0:19 0:6 27:62 0:0 0:2 0:0 0:0
Benzo(b)fluoranthene 0:16 0:19 0:6 9:62 0:0 0:2 0:0 0:0
Benzo(k)fluoranthene 0:16 0:19 0:6 0:62 0:0 0:2 0:0 0:0
Chrysene 0:16 0:19 0:6 30:62 0:0 0:2 0:0 0:0
Dibenz(a,h)anthracene 0:16 0:19 0:6 0:62 0:0 0:2 0:0 0:0
Indeno[1,2,3-cd]pyrene 0:16 0:19 0:6 0:62 0:0 0:2 0:0 0:0
Benzoic acid 1:18 0:18 0:6 62:62 0:0 0:2 0:0 0:0
beta-hexachlorocyclohexane 0:57 0:83 0:9 0:27 0:0 0:0 0:0 0:0
bis(2-chloroethyl)ether 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
bis(2-ethylhexyl)phthalate 4:18 4:18 1:6 2:62 0:0 0:2 0:0 0:0
bis-chloroisopropyl ether 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
Butyl benzyl phthalate 0:0 0:0 0:6 0:62 0:0 0:2 0:0 0:0
Cadmium 0:0 0:0 0:3 63:63 0:0 2:2 0:0 0:0
Carbazole 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
alpha Chlordane 24:57
50:83
3:9
0:0
0:0
0:0 0:0 0:0
gamma-Chlordane 8:57 15:83 1:9
0:0
0:0
0:0 0:0 0:0
Chlordane 0:0 0:0 0:0 0:27 0:0 0:0 0:0 0:0
Chromium 0:0 0:0 2:3 59:63 0:0 2:2 0:0 0:0
Dieldrin 4:57 6:83 0:9 0:27 0:0 0:0 0:0 0:0
Diethyl phthalate 0:18 0:18 0:6 0:62 0:0 0:0 0:0 0:0
Di–butyl phthalate 0:18 0:18 1:6 0:62 0:0 0:0 0:0 0:0
Di–octyl phthalate 0:18 0:18 0:6 0:62 0:0 0:0 0:0 0:0
Endosulfan sulfate 0:57 0:83 0:9 0:27 0:0 0:0 0:0 0:0
Endrin 0:57 0:83 0:9 0:27 0:0 0:0 0:0 0:0
Fluoranthene 0:18 0:18 0:6 30:62 0:0 0:2 0:0 0:0
Fluorene 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
gamma-hexachlorocyclohexane 0:57 1:83 0:9 0:27 0:0 0:0 0:0 0:0
Heptachlor 0:57 0:83 0:9 0:27 0:0 0:0 0:0 0:0
Heptachlor epoxide 0:57 0:83 0:9 0:27 0:0 0:0 0:0 0:0
Hexachlorobenzene 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:9
Hexachlorobutadiene 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
Hexachlorocyclopentadiene 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
Hexachloroethane 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
Isophorone 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
Methoxychlor 0:57 0:83 0:9 0:27 0:0 0:0 0:0 0:0
Methylmercury 16:16 19:19 33:33 62:62 5:11 3:3 8:9 8:8
Naphthalene 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
Nitrobenzene 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
-Nitrosodimethylamine 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
-Nitroso-di–propylamine 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
-Nitrosodiphenylamine 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
PCBs (total-calc'd) 45:55 72:83 30:30 60:60 11:11 3:3 9:9 5:5
Pentachlorophenol 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
Phenol 0:18 0:18 0:6 0:63 0:0 0:2 0:0 0:0
Pyrene 0:18 0:18 0:6 26:62 0:0 0:2 0:0 0:0
Toxaphene 0:57 0:83 0:9 0:27 0:0 0:2 0:0 0:0
Tributyltin 0:0 0:0 7:24 60:60 11:11 2:3 0:9 0:0


Table F3. Frequency of detection for contaminants without screening values in Lower Duwamish Waterway Fish Seattle, Washington

Frequency of detection for contaminants without screening values in Lower Duwamish Waterway Fish Seattle, Washington

  Frequency Detected: Number of Analyses
Contaminant Coho Chinook English Sole mussels perch Dungeness Rock Crab Rockfish
1,3-Dichlorobenzene 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
2-Methylnaphthalene 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
2-Methylphenol 0:18 0:18 0:6 53:62 0:0 0:2 0:0 0:0
2-Nitroaniline 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
2-Nitrophenol 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
3-Nitroaniline 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
4-Bromophenyl phenyl ether 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
4-Chloro-3-methylphenol 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
4-Chlorophenyl phenyl ether 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
4-Methylphenol 0:18 0:18 0:6 2:62 0:0 0:2 0:0 0:0
4-Nitroaniline 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
4-Nitrophenol 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
Acenaphthylene 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
alpha-hexachlorocyclohexane 6:57 6:83 0:9 0:27 0:0 0:0 0:0 0:0
alpha-Endosulfan 0:57 0:83 0:9 0:27 0:0 0:2 0:0 0:0
Aroclor-1016 0:57 0:83 0:9 0:62 0:0 0:2 0:0 0:5
Aroclor-1016/1242 0:0 0:0 3:3 0:0 8:11 1:1 9:9 0:0
Aroclor-1221 0:57 0:83 0:9 0:62 0:0 0:2 0:0 0:5
Aroclor-1232 0:57 0:83 0:9 0:62 0:0 0:2 0:0 0:5
Aroclor-1242 0:57 0:83 0:9 0:62 0:0 0:2 0:0 0:5
Aroclor-1248 0:57 0:83 7:30 0:62 0:11 1:3 0:9 0:5
Aroclor-1260 42:47 71:72 30:30 0:62 11:11 3:3 9:9 5:5
Benzo(g,h,i)perylene 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
Benzyl alcohol 0:18 0:18 0:6 6:62 0:0 0:2 0:0 0:0
beta-Endosulfan 0:57 0:83 0:9 0:27 0:0 0:0 0:0 0:0
bis(2-chloroethoxy)methane 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
Cobalt 0:0 0:0 0:0 29:29 0:0 0:0 0:0 0:0
Copper 18:18 18:18 9:9 62:62 0:0 2:2 0:0 0:0
Coprostanol 0:6 0:6 0:6 0:62 0:0 0:2 0:0 0:0
delta-hexachlorocyclohexane 0:57 0:83 0:9 0:27 0:0 0:0 0:0 0:0
Dibenzofuran 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
Dibutyltin 0:0 0:0 0:0 0:28 0:0 0:0 0:0 0:0
Dimethyl phthalate 0:18 0:18 0:6 0:62 0:0 0:2 0:0 0:0
Endrin aldehyde 0:57 0:83 0:9 0:27 0:0 0:0 0:0 0:0
Lead 1:18 0:18 0:9 62:62 0:0 2:2 0:0 0:0
Molybdenum 0:0 0:0 0:0 25:25 0:0 0:0 0:0 0:0
Monobutyltin 0:0 0:0 0:0 18:28 0:0 0:0 0:0 0:0
Nickel 0:0 0:0 0:3 62:62 0:0 2:2 0:0 0:0
Phenanthrene 0:18 0:18 0:6 13:62 0:0 0:2 0:0 0:0
Silver 0:0 0:0 0:3 7:62 0:0 2:2 0:0 0:0
Vanadium 0:0 0:0 0:0 18:18 0:0 0:0 0:0 0:0
Zinc 0:0 0:0 3:3 62:62 0:0 2:2 0:0 0:0


Table F4. Selection of contaminants of concern in Lower Duwamish Waterway fish Seattle, Washington
Contaminant Maximum Comparison Valueb COC?
Chinook Salmon Coho Salmon English Sole Quillback Rockfish Red Rock Crab Dungeness Crab a Perchc mussels
Arsenic (mg/kg) 1.4 1.6 15 NA NA 12.5 1.4 1.1 0.003 Yes
Benzoic Acid (mg/kg) <0.3 0.65 <0.1 NA NA <0.1 NA 12 1900 No
Bis(2ethylhexyl)pthalate (ug/kg) 5350 4750 <0.1 NA NA <16 NA 0.2 351 Explain
Cadmium (mg/kg) NA NA <0.05 NA NA <0.02 NA 0.7 0.5 Yes
Chlordane (ug/kg) 15.4 2.5 3.4 NA NA NA NA <7 14 Yes
Chromium (mg/kg) NA NA 0.16 NA NA <0.2 NA 0.2 1.5 No
cPAHs (ug/kg) <46 <43 <31 NA NA <29 NA 40 0.7 Yes
Di–butyl pthalate (ug/kg) <50 <50 56 NA NA NA NA 59 49000 No
DDD (ug/kg) 4.8 3.2 4.7 <0.1 NA NA NA <1.3 20 No
DDE (ug/kg) 33.8 17.4 5.3 <0.1 NA NA NA <1.3 14 Yes
DDT (ug/kg) 2.7 <2 <2 <0.1 NA NA NA <1.3 14 No
Fluoranthene (ug/kg) <20 <20 <24 NA NA <16 NA 123 19600 No
PCBs (ug/kg) 160 97 640 428 204 177 228 73 2 Yes
Pyrene (ug/kg) <50 <50 <24 NA NA <16 NA 122 14000 No
Mercury (ug/kg) 150 52 83 567 130 111 60 16 49 Yes
Tributyltin (ug/kg) NA NA 50 NA <2 82 25 93 147 No

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