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PUBLIC HEALTH ASSESSMENT

LOWER DUWAMISH WATERWAY
SEATTLE, KING COUNTY, WASHINGTON

APPENDIX F: CONTAMINANT SCREENING PROCESS (Cont.)

Table F5. Frequency of detection for contaminants with screening values and selection of contaminants of concern in Lower Duwamish Waterway sediment Seattle, Washington

Frequency of detection for contaminants with screening values in LDW sediment

Frequency detected : Frequency analyzed

count 95^th % (ppm) Comparison Value (ppm)
Source
Contaminant of Concern?

1,1,1,2-Tetrachloroethane 0:47 No

1,1,1-Trichloroethane 0:61 No

1,1,2,2-Tetrachloroethane 0:61 No

1,1,2-Trichloroethane 0:61 No

1,1,2-Trichlorotrifluoroethane 0:59 No

1,1-Dichloroethane 0:61 No

1,1-Dichloroethene 0:61 No

1,1-Dichloropropanone 0:45 No

1,1-Dichloropropene 0:47 No

1,2,3-Trichlorobenzene 0:47 No

1,2,3-Trichloropropane 0:47 No

1,2,4-Trichlorobenzene 23:807 0.110 500 RMEG No

1,2-Dibromo-3-chloropropane 0:47 No

1,2-Dichlorobenzene 75:801 0.110 5000 RMEG No

1,2-Dichloroethane 0:61 No

1,2-Dichloroethene 0:2 No

1,2-Dichloropropane 0:61 No

1,2-Diphenylhydrazine 1:216 0.120 0.9 CREG No

1,3-Dichlorobenzene 25:788 0.110 16 Region 9 No

1,3-Dichloropropane 0:47 No

1,3,4-Trimethylbenzene 2:47 0.004 NA NA No

1,3,5-Trimethylbenzene 1:47 0.004 21 Region 9 No

1,4-Dichlorobenzene 151:804 0.130 41.7 MTCA No

1-Chlorobutane 0:47 No

1-Methylnaphthalene 3:3 0.041 4000 EMEG No

2-Chloroethylvinyl ether 0:12 No

2,2-Dichloropropane 0:47 No

2,4,5-Trichlorophenol 1:734 0.590 5000 RMEG No

2,4,6-Trichlorophenol 1:734 0.577 60 CREG No

2,4-Dichlorophenol 1:734 0.340 200 RMEG No

2,4-Dimethylphenol 8:779 0.331 1000 RMEG No

2,4-Dinitrophenol 2:726 1.100 100 RMEG No

2,4-Dinitrotoluene 1:734 0.564 100 EMEG No

2,6-Dinitrotoluene 1:734 0.564 80 MTCA No

2-Chloronaphthalene 1:734 0.110 4000 RMEG No

2-Chlorophenol 1:734 0.120 300 RMEG No

2-Chlorotoluene 0:47 No

2-Hexanone 0:61 No

2-Methylnaphthalene 117:811 0.130 NA NA No

2-Methylphenol 10:811 0.220 3100 Region 9 No

2-Nitroaniline 1:726 0.590 1.7 Region 9 No

2-Nitrophenol 1:734 0.570 NA NA No

2,4'-DDD 0:3 No

2,4'-DDE 0:3 No

2,4'-DDT 0:3 No

2-Nitropropane 0:47 No

3-Nitroaniline 0:688 No

3,3'-Dichlorobenzidine 2:668 0.590 2 CREG No

4-Bromophenyl phenyl ether 1:734 0.120 NA NA No

4-Chloro-3-methylphenol 1:726 0.240 NA NA No

4,4'-DDD 20:219 0.020 3 CREG No

4,4'-DDE 40:219 0.012 2 CREG No

4,4'-DDT 16:219 0.020 2 CREG No

4-Chloroaniline 3:649 0.356 200 RMEG No

4-Chlorophenyl phenyl ether 1:734 0.120 NA NA No

4-Chlorotoluene 0:47 No

4-Methylphenol 50:473 0.400 310 Region 9 No

4-Nitroaniline 2:672 0.590 NA NA No

4-Nitrophenol 1:726 0.570 NA NA No

Acenaphthene 317:811 0.255 3000 RMEG No

Acenaphthylene 82:811 0.110 NA NA No

Acetone 5:61 0.162 5000 RMEG No

Aldrin 2:215 0.005 2 RMEG No

Allyl Chloride 0:47 ^No

Aluminum 684:691 29000 76000 Region 9 No

Ammonia 81:81 74 20000 Int. EMEG No

Aniline 2:126 0.110 100 RMEG No

Anthracene 560:812 0.420 20000 RMEG No

Antimony 163:647 13 20 RMEG No

Aroclor-1016 3:984 0.080 4 RMEG No

Aroclor-1221 2:781 0.054 0.220 Region 9 No

Aroclor-1232 2:781 0.030 0.220 Region 9 No

Aroclor-1242 136:984 0.319 0.220 Region 9 Total PCBs

Aroclor-1248 208:983 0.869 0.220 Region 9 Total PCBs

Aroclor-1254 731:987 1.800 1 EMEG Total PCBs

Aroclor-1260 745:986 2.400 0.220 Region 9 Total PCBs

Arsenic 789:887 30 20 EMEG Yes

Barium 609:609 153 4000 RMEG No

Benzene 1:61 0.006 10 CREG No

Benzidine 2:16 1.350 0.003 CREG Too Few

Benzo(a)anthracene + Chrysene 735:813 1.100 0.137 MTCA cPAHs

Benzo(a)pyrene 719:812 1.045 0.100 CREG cPAHs

Benzo(b)fluoranthene 701:784 1.600 0.137 MTCA cPAHs

Benzo(g,h,i)perylene 684:812 0.570 NA NA No

Benzo(k)fluoranthene 674:784 0.910 0.137 MTCA cPAHs

Benzoic acid 71:786 1.100 200000 RMEG No

Benzyl alcohol 14:799 0.511 24000 MTCA No

Beryllium 672:708 0.6 50 EMEG No

Biphenyl 2:2 0.030 3000 RMEG No

bis(2-chloroethyl)ether 0:734 No

bis(2-chloroisopropyl)ether 0:734 No

Bis(2-chloroethoxy) methane 2:734 0.120 NA NA No

bis(2-ethylhexyl)phthalate 701:820 4.010 71.4 MTCA No

Bromobenzene 0:47 No

Bromochloromethane 0:47 No

Bromodichloromethane 0:61 No

Bromoform 0:61 No

Bromomethane 0:61 No

Butyl benzyl phthalate 437:818 0.360 10000 RMEG No

Cadmium 617:869 4 10 EMEG No

Carbazole 377:734 0.320 50 MTCA No

Carbon disulfide 18:61 0.018 5000 RMEG No

Carbon tetrachloride 0:61 No

Chlordane 12:126 0.040 2 CREG No

alpha-Chlordane 1:89 0.025 No

trans-Chlordane 4:85 0.025 No

Chlorobenzene 0:61 No

Chloroethane 0:61 No

Chloroform 1:61 0.006 500 EMEG No

Chloromethane 0:61 No

Chromium 830:845 70 210 Region 9 No

Chromium VI 1:20 15 200 RMEG No

Chrysene 759:813 1.540 0.137 MTCA cPAHs

cis-1,2-Dichloroethene 1:59 0.004 NA NA No

cis-1,3-Dichloropropene 0:61 No

Cobalt 459:474 14 4700 Region 9 No

Copper 876:887 147 2960 MTCA No

Coprostanol 84:227 2.4 NA NA No

Cyanide 1:25 49 1000 RMEG No

Cymene 3:47 0.004 NA NA No

Dibenzo(a,h)anthracene 413:812 0.205 0.137 MTCA cPAHs

Dibenzofuran 240:810 0.150 290 Region 9 No

Dibromochloromethane 0:61 No

Dibutyltin 88:139 0.051 NA NA No

Dichloromethane 1:61 0.020 NA NA No

Dichlorodifluoromethane 0:9 No

Dieldrin 21:215 0.010 0.04 CREG No

Diethyl ether 0:47 No

Diethyl phthalate 9:818 0.120 40000 RMEG No

Dimethyl phthalate 132:818 0.120 80000 MTCA No

Di�butyl phthalate 251:818 0.282 5000 RMEG No

Di�octyl phthalate 50:819 0.130 20000 int EMEG No

Dioxin/furan TCDD toxicity equivalent 29:29 0.0001 0.00005 EMEG Explain

Endosulfan 0:92 No

Endosulfan sulfate 2:158 0.010 No

Endrin 0:175 No

Endrin aldehyde 5:158 0.020 NA NA No

Endrin ketone 2:85 0.020 NA NA No

Ethyl Methacrylate 0:47 No

Ethylbenzene 1:95 0.009 5000 RMEG No

Ethylene bromide 0:47 No

Fluoranthene 778:813 2.900 2000 RMEG No

Fluorene 389:811 0.245 2000 RMEG No

Gasoline 0:24 No

Heavy oil 5:13 4580 200 MTCA Explain

Heptachlor 4:214 0.005 0.200 CREG No

Heptachlor epoxide 3:176 0.006 0.08 CREG No

Hexachlorobenzene 50:806 0.110 0.4 CREG No

Hexachlorobutadiene 1:811 0.220 9 CREG No

alpha-Hexachlorocyclohexane 0:175 No

beta-Hexachlorocyclohexane 1:175 0.005 0.4 CREG No

delta-Hexachlorocyclohexane 1:95 0.004 NA NA No

gamma-BHC 5:210 0.005 20 RMEG No

Hexachlorocyclopentadiene 2:618 0.590 300 RMEG No

Hexachloroethane 1:793 0.220 50 CREG No

Indeno(1,2,3-cd)pyrene 688:813 0.620 0.137 MTCA cPAHs

Iron 689:689 39520 23000 Region 9 Explain

Isophorone 0:733 No

Isopropylbenzene 0:47 No

Lead 876:887 260 400 Region 9 No

Magnesium 636:636 9800 NA NA No

Manganese 652:652 619 3000 Region 9 No

Mercury 748:875 0.6 24 MTCA Fish Pathway

Methacrylonitrile 47:47 0.018 5 RMEG No

Methoxychlor 6:175 0.016 300 RMEG No

Methyl Acrylate 0:47 No

Methyl ethyl ketone 18:61 0.024 48000 MTCA No

Methyl-t-butyl ether 0:47 No

Methyl iodide 0:47 No

Methyl methacrylate 0:47 No

Methylmercury 59:59 0.002 5 RMEG No

Methylene bromide 0:47 No

Mirex 0:3 No

Molybdenum 37:156 6 300 RMEG No

Naphthalene 129:811 0.130 1000 RMEG No

Nickel 856:873 37 1000 RMEG No

Nitrobenzene 0:734 No

Nitrosodimethylamine 0:216 No

Nitrosodipropylamine 0:734 No

Nitrosodiphenylamine 20:811 0.120 100 CREG No

Octadecanal 2:2 1.1 NA NA No

Pentachloroethane 0:47 No

Pentachlorophenol 13:759 0.590 6 CREG No

Phenanthrene 741:813 1.5 NA NA No

Phenol 229:811 0.300 30000 RMEG No

Polychlorinated Biphenyl Dioxin-like Congeners 0.00009 0.000007 MTCA Explain

PCB 77 20:662

PCB 81 0:333

PCB 105 470:657

PCB 114 9:333

PCB 118 582:661

PCB 123 0:333

PCB 126 16:661

PCB 156 253:659

PCB 157 76:657

PCB 167 56:333

PCB 169 0:659

PCB 189 30:659

Propylbenzene 0:47 No

Pyrene 768:813 2.600 2000 RMEG No

Selenium 303:697 20 300 EMEG No

Silver 586:869 2 300 RMEG No

Styrene 0:61 No

Tetrabutyltin 11:153 0.020 NA NA No

Tetrachloroethene 3:90 0.009 19.6 MTCA No

Thallium 355:707 36 5.2 Region 9 Explain

Tin 229:351 15 48000 MTCA No

Toluene 6:61 0.006 10000 RMEG No

Total Petroleum Hydrocarbons 65:73 4300

Total Polynuclear Aromatic Hydrocarbons 599:613 16 NA NA No

Total Polychlorinated Biphenyls 1194:1325 4.446 0.4 CREG Yes

Total Tetrachlorodibenzo-p-dioxins 23:30 0.00002 0.000007 MTCA Explain

Total of 6 isomers: pp,op-DDT,-DDD,-DDE 83:213 0.080 NA NA No

Toxaphene 0:175 No

TPH - Diesel 6:31 1415 200 MTCA Explain

TPH - Gasoline Range 0:8 No

TPH - Heavy Fuel Oil Range 2:8 328 200 MTCA Too Few

Tributyltin 130:154 0.312 20 RMEG Fish Pathway

Trichloroethene 4:95 0.010 91 MTCA No

Trichlorofluoromethane 0:59 No

Vanadium 474:474 81 560 MTCA No

Vinyl acetate 0:12 ^No

Vinyl chloride 0:61 No

Ortho-xylene 1:56 0.004 10000 int EMEG No

Total xylenes 0:43 No

m,p-Xylene 1:56 1 10000 int EMEG No

Zinc 872:886 360 20000 EMEG No

Screening rationale

Generally speaking, contaminants that exceeded screening criterion were considered to be of concern and were evaluated further. In some cases, contaminants exceeded screening criterion, but were not considered as contaminants of concern for other reasons. These explanations are listed below.

Background levels

Iron was found in sediment at levels that exceeded the Region 9 PRG. This level, however, is well within the background range of iron that occurs naturally in the Puget Sound region soils. The 95^th percentile of iron found in LDW sediments (39520 ppm) much lower than the 90^th percentile of background in the Puget Sound region (58700 ppm).

Toxicological Reasons

Thallium was found in sediment at levels that exceeded the Region IX PRG. The reference dose used to calculate the PRG is based on thallium sulfate, and the critical effect for that chemical is alopecia (hair loss) in female rats. This endpoint is weak, and therefore, thallium in sediment is not considered to be of great concern.

Bis(2-ethylhexyl)pthalate (DEHP) was found in coho and Chinook at levels that exceeded a calculated comparison value. DEHP is a chemical for which there appears to be a threshold for carcinogenicity. In other words, there is a dose of DEHP below which there is no cancer risk, but above which results in some cancer risk. The evidence for this threshold comes from studies of rats and mice dosed with DEHP. Liver cancer in these animals is thought to result from the process of peroxisome proliferation after exposure to DEHP. Without peroxisome proliferation, there were no signs of carcinogenicity. Studies determined a NOEL for peroxisome proliferation at 20 mg/kg/day in mice. Furthermore, rats and mice are considered to be especially sensitive to peroxisome proliferation compared to humans and other primates. Based on this information, a margin of exposure (MOE) of 10 was determined to be protective for potential risks to humans from DEHP exposure.^(f) For comparison purposes, a dose calculation for a subsistence consumer of chinook is shown below because the highest level of DEHP in LDW tissue was found in a chinook sample.

DEHP dose =C x IR

Concentration [C] - 5.4 mg/kg

Fish Ingestion Rate (IR) - 0.00058 kg fish / kg body weight /day

DEHP dose = 5.4 mg/kg * 0.00058 kg fish / kg body weight /day

= 0.003 mg/kg/day

This dose can be used in conjunction with the observed NOAEL from the mice study to determine a margin of exposure (MOE) for this consumption scenario.

Margin of Exposure = NOAEL / Dose

= 20 mg/kg/day / 0.003 mg/kg/day
= 6700

An MOE of 10 was determined to be protective of human health with regard to DEHP exposure, and an MOE of 6,700 was obtained using a reasonable conservative exposure scenario. In other words, the exposure scenario resulted in a MOE that was more than three orders of magnitude more protective than a MOE that is considered to be protective. For this reason, DEHP was not considered a contaminant of concern.

Too few samples

Though there were data for more than 1000 sediment samples from the LDW, many chemicals were analyzed infrequently. Among them were some chemicals that may have been detected in a few samples, but in too few samples with which to conduct a worthwhile assessment over a wide area. The lack of complete data is a great source of uncertainty. The contaminants below met initial screening requirements, but were not evaluated due to the low number of samples. In general, fewer than 50 samples over the entire waterway was considered to be a paucity.

Benzidine - detected in 2 of 16 sediment samples.

Total Petroleum Hydrocarbons (diesel range) - detected in 6 of 31 samples.

Total Petroleum Hydrocarbons (gasoline range) - detected in 2 of 8 samples.

Heavy Oil - detected in 5 of 13 samples.

Total TCDD - detected in 29 of 29 samples.

APPENDIX G: RESPONSE TO PUBLIC COMMENTS

The draft public health assessment was released for comment on July 11, 2002. The public was given an opportunity to provide comments to DOH, and attempts were made to address all of them. Some comments were addressed by simply amending the text within the document, while others comments are responded to below.

1. The contaminant screening process in the draft public health assessment is difficult to follow.

Efforts were made to make the screening process more transparent. Appendix F shows the contaminant screening process.

2. There seems to be discrepancies with the conclusions of the Public Health Assessment and the Remedial Investigation conducted by the LDWG. For example, the RI concluded that arsenic, cPAHs, and PCBs were the largest contributors to risk in that order, and the PHA states that the main contaminants of concern are PCBs and mercury. Please explain these discrepancies.

The health assessment and the Remedial Investigation each use similar methods in assessing risk or hazards associated with the LDW site. However, there are some different assumptions and approaches made in each document because the purposes of the Remedial Investigation and public health assessment are different. The RI is designed to support site-specific decisions on the need for cleanup and remediation. The health assessment is more qualitative and is designed to determine the relative hazard associated with the site and need for any recommendations to reduce exposure.

Using cPAHs as an example, the remedial investigation presented relatively high cancer risks associated with consumption of LDW fish contaminated with cPAHs; however, there were not any finfish or crabs that had detected levels of cPAHs in their tissues. The cancer risks presented in the RI were based on assumptions that the fish contained � of the limit of detection. While this is a sound approach for determining potential data gaps for the baseline risk assessment (i.e., necessary to get detection lower detection limits for cPAH levels in finfish), no reliable conclusion could be made regarding health hazards from such a data set.

PCBs, on the other hand, were detected in all fish species. Hazard quotients associated with PCB exposure ranked highest in all the fish exposure scenarios. This resulted in a fish advisory for the general population based on immune effects of PCBs and for pregnant women or those considering pregnancy based the combined developmental effects of PCBs, mercury, and DDE.

3. Crab consumption should be included as a completed pathway of exposure based on reports from WDFW that observed people harvesting crabs from the LDW. Furthermore, LDW crab consumption would clearly result in elevated health risks which is further compounded by the consumption habits of LDW API consumers. The elevated risk needs to be recognized and clearly stated.

DOH recognizes that crabs are being caught from the LDW (though we do not know how many or how often), and have considered the crab consumption pathway as a completed pathway of exposure in the final version of the PHA. DOH also recognizes that, based on sparse data, consumption of Dungeness crab might result in an elevated health risk, but only three individual Dungeness crab samples are used to calculate risk and hazard associated with the consumption of this species. Red rock crab samples are more numerous and also contained PCB and mercury levels, therefore, crab consumption limits are included in the recommendation section of this document. We also recognize that API consumers might eat the entire crab. Data from Elliot bay and other studies indicate that the hepatopancreas in crabs tends to accumulate contaminants. Therefore, the PHA recommends that this organ not be eaten.

4. The PHA reported risks for exposure from direct contact to sediment in the 10^-6 range which according to DOH's classification system would indicate a slight increase in cancer risk. Yet DOH concludes that "exposure to sediments in the LDW represents no apparent public health hazard."

All sediment exposure scenarios resulted in doses that were well below noncancer reference doses which indicates that exposure to LDW sediments is not expected to result in adverse noncancer health effects. Cancer risk attributable to direct contact with LDW sediments is lower than 1 x 10^-5. Exposure to carcinogenic chemicals at any level will result in some theoretical risk if it is assumed that there is no threshold. Regulatory decisions are usually made when a risk of cancer exceeds a probability of 1 x 10^-6 to 1x10^-4. The purpose of this health assessment is not to establish cleanup levels in sediment, but to inform people of their potential risks.

5. The text states that DOH advises against harvesting shellfish from King County, "except for Vashon/Maury Island." As DOH is aware, serious health concerns related to arsenic contamination exist on Vashon/Maury Island. In light of this, DOH should update its advisory to include the Vashon/Maury Island shoreline.

Vashon/Maury Island is outside the scope of this document. However, the DOH Office of Food Protection and Shellfish Programs has not found higher levels of arsenic in shellfish from King County or Vashon Island compared to other parts of Puget Sound. In fact, the arsenic levels found have been very consistent throughout Puget Sound regardless whether the shellfish tested came from pristine areas or urbanized areas (or areas downwind of Asarco). Advice from DOH against harvesting shellfish from King County's urbanized east shore beaches is based primarily on microbial contamination concerns.

6. WA DOH lists the EMEG Comparison Value of 20 ppm for arsenic in soil. Washington State is well aware that this is not a protective value for arsenic. WA DOH should consult with the Washington State Department of Ecology (Ecology) and others regarding appropriate human health protective levels for arsenic. Ecology records indicate that 0.67 ppm has been determined to be protective.

Ecology has established 20 ppm as the cleanup level for arsenic in residential soil. The cleanup levels is based on an upper-bound of background concentrations in Washington State. Ecology does acknowledge that 0.67 ppm would be protective based on a 10^-6 increased cancer risk, but that level is well below naturally occurring levels in soil.

7. The PHA states that, "factors such as background exposure are considered when formulating conclusions." Yet nowhere in the document are existing body burdens of chemicals presented, discussed or apparently considered in determining health effects. Please present information on existing body burdens of chemicals such as lead, mercury, PCBs, arsenic and others, and explain how these pre-existing body burdens are taken into account when determining the impacts of sediment exposure and consumption of Duwamish River fish.

Generally, the PHA attempts to determine the risk for adverse health effects that would occur as a result of exposure at a site. These risks often need to be put into perspective by comparing them to risks that we receive as part of our daily lives. An example of this can be seen in fish contaminant levels. PCB levels are higher in LDW English sole compared to nonurban areas of Puget Sound, but mercury levels are similar. This indicates that risk associated with PCBs is more of a site related problem (even though PCBs are found in all fish), whereas risk associated with mercury reflects regional conditions. Cleanup of the Duwamish River will have a future impact on PCB levels in resident fish, but may not have a huge impact with regard to mercury levels.

8. Are there no existing data on toxicological mixtures for chemicals found in the Duwamish River, at recorded levels? At a minimum, known synergistic effects for chemicals present in the river should be presented, with a discussion of any uncertainties associated with reaching conclusions in specific field circumstances.

ATSDR's Division of Toxicology recently prepared a draft interaction profile for persistent chemicals found in fish. The weight-of-evidence analyses of available data on the joint toxic action of mixtures of these components indicate that scientific evidence for greater-than-additive or less-than-additive interactions among these components is limited and inadequate for characterizing the possible modes of joint action on most of the pertinent toxicity targets. Therefore, it is recommended that additivity be assumed as a public health protective when assessing exposure to mixtures of these contaminants.

9. The PHA states that, "little difference exists between contaminant levels in salmon caught from the LDW versus other areas of Puget Sound." Yet Table 7 appears to contradict this statement, especially for Aroclor-1254 levels in coho. Please present the results of a statistical analysis that would help to explain this discrepancy.

A recent statistical analysis performed by the WDFW at the request of DOH compared PCB levels in Duwamish River coho with those from nonurban basins in Puget Sound. The analysis took into consideration several factors such as lipid content, whether the fish were hatchery reared or wild, gender, and size. While PCB levels in Duwamish coho were significantly higher than those from the Nooksack and Skagit rivers, they were not significantly different than those from the Nisqually or Deschutes rivers. This result supports the notion that difference in the level of PCBs in the south Puget Sound is at least in part related to the amount of time coho spend feeding in Puget Sound.

10. The PHA states that in the case of average consumers, salmon consumption from the LDW is not expected to pose a risk for any noncancer health effects and for high-end consumers states that the doses are still well below actual toxic effects (due to safety factors applied). Given the potential risks indicated using approved methodologies, advising the public to disregard the potential risks indicated appears irresponsible.

One of the difficulties in communicating health risks attributable to fish consumption is balancing the very real health benefits of eating fish versus theoretical or uncertain risks. Salmon are often regarded as being a relatively "clean" fish that have a high level of omega-3 fatty acids which reduce the risk of heart disease, and have other health benefits. For this reason, people are often advised to eat salmon and other low contaminant fish as opposed to fish that typically have high levels of contaminants. DOH agrees that there is a risk of eating an unlimited amount of salmon, or any other fish in the world, for that matter. DOH considers salmon the preferred fish to eat from the LDW due to the relatively low level of contaminants, and the high level of omega-3 fatty acids. Consumption limits have not been set for LDW salmon due to the health benefits.

11. A discussion of cancer risk from consuming salmon should be presented, especially in light of recent studies on the Columbia River determining that salmonid consumption there poses an unacceptable cancer risk to tribal fishers. A comparison of fish tissue and sediment concentrations between the Columbia and Duwamish Rivers should be provided.

EPA's Columbia River Basin Fish Contaminant Survey reported individual cancer risks of 1 x 10^-3 associated with a high-end consumers of coho, Chinook, Steelhead, Eulachon, and Pacific Lamprey. The majority of these cancer risks were attributable to arsenic, and dioxin TEQ (includes dioxin-like PCB congeners).

The cancer risk associated with a high-end consumer of all anadromous fish from the LDW is 9 x 10^-4 (Table C5). The majority of this risk is attributable to cPAHs and arsenic. It is important to reemphasize that cPAHs were not detected in any finfish, and the amount of inorganic arsenic assumed to be in finfish is uncertain. A key difference between the data that were available for the Columbia River Basin Fish Contaminant Survey and the data used in the PHA was that there was no dioxin TEQ data available in the LDW fish.

Aroclor levels in the few Columbia River Basin salmon do appear to be lower than in LDW salmon, however, there may be explanations for these differences based on the geographic differences of the two waterways. For instance, many of the fish in the Columbia were sampled from fresh water locations a great distance from salt water whereas LDW salmon were sampled in a marine environment or in brackish water. Returning salmon stop feeding as they swim up fresh water streams relying solely on their fat reserves. In the process of mobilizing their fat, they release PCBs into their blood stream where it is either repartitioned to remaining fat, other organs, or excreted. A comparison between these two different populations of coho, therefore, is not appropriate.

12. The PHA concludes that there is no apparent public health hazard associated with children's contact with contaminated sediment at public access locations. The RI identified potential sediment data gap near public access points.

The PHA acknowledges a paucity of intertidal sediment samples near public access areas. However, it was assumed that the 1,200 samples taken from the LDW were taken in areas thought to be contaminated, thus being biased toward finding areas with the most contamination. While this may not be true in all cases, it was assumed that the sediment was adequately characterized with respect to direct contact pathway. DOH understands that more sediment sampling may occur at public access areas and will reevaluate the data once they are available.

13. Why does the PHA consider that all the seafood people consumes comes from the LDW?

In terms of assessing hazards associated with a site, DOH chose to evaluate a worst-case scenario. The results of the evaluation revealed that a subsistence level consumption of resident fish from the LDW could result in adverse health effects. Based on this, DOH has issued a fish advisory for resident fish in the Duwamish River (See Recommendations on page 58). Furthermore, consumers that eat a lot of fish as a routine part of their diet should avoid eating resident fish from the LDW due to the fact that all fish have some level of contamination.

14.What consideration was given to lead exposure at beaches?

Lead was not considered as a contaminant of concern in sediment because the 95^th percentile lead concentration of all sediment samples was below the comparison value (see table F5). However, 32 sediment samples contained lead above comparison values, and nearly half of those samples were taken from a single area. None of the samples with elevated lead levels were located at or near public access areas. EPA and LDWG plan to further characterize sediment contaminant levels near public access points at which time DOH will be available to reevaluate lead and other contaminant exposure at public beaches.

15. EPA's revised guidelines for assessing cancer risks to children should be used to reassess cancer risks for children in the Public Health Assessment for the Lower Duwamish River.

See the child health considerations section on page 48.

CERTIFICATION

The Washington State Department of Health prepared this public health assessment under a cooperative agreement with the Agency for Toxic Substances and Disease Registry (ATSDR). The document is in accordance with aproved methodology and procedures existing at the time the health assessment was begun.

Debra Gable
Technical Project Officer,
SPS, SSAB, DHAC
ATSDR

The Division of Health Assessment and Consultation, ATSDR has reviewed this public health assessment and concurs with the findings.

Lisa C. Hayes
for Roberta Erlwein
Section Chief,
SPS, SSAB, DHAC
ATSDR

^f Doull J, Cattley R, Elcombe C, Lake BG, Swenberg J, Wilkinson C Williams G, and van Gemert M. A cancer risk assessment of di(2-ethylhexyl)phthalate: Application of the new U.S. EPA Risk Assessment Guidelines. Regulatory Toxicology and Pharmacology 29: 327-357 (1999).

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Frequency of detection for contaminants with screening values in LDW sediment
Frequency detected : Frequency analyzed
	count	95^th % (ppm)	Comparison Value (ppm)	Source	Contaminant of Concern?
1,1,1,2-Tetrachloroethane	0:47				No
1,1,1-Trichloroethane	0:61				No
1,1,2,2-Tetrachloroethane	0:61				No
1,1,2-Trichloroethane	0:61				No
1,1,2-Trichlorotrifluoroethane	0:59				No
1,1-Dichloroethane	0:61				No
1,1-Dichloroethene	0:61				No
1,1-Dichloropropanone	0:45				No
1,1-Dichloropropene	0:47				No
1,2,3-Trichlorobenzene	0:47				No
1,2,3-Trichloropropane	0:47				No
1,2,4-Trichlorobenzene	23:807	0.110	500	RMEG	No
1,2-Dibromo-3-chloropropane	0:47				No
1,2-Dichlorobenzene	75:801	0.110	5000	RMEG	No
1,2-Dichloroethane	0:61				No
1,2-Dichloroethene	0:2				No
1,2-Dichloropropane	0:61				No
1,2-Diphenylhydrazine	1:216	0.120	0.9	CREG	No
1,3-Dichlorobenzene	25:788	0.110	16	Region 9	No
1,3-Dichloropropane	0:47				No
1,3,4-Trimethylbenzene	2:47	0.004	NA	NA	No
1,3,5-Trimethylbenzene	1:47	0.004	21	Region 9	No
1,4-Dichlorobenzene	151:804	0.130	41.7	MTCA	No
1-Chlorobutane	0:47				No
1-Methylnaphthalene	3:3	0.041	4000	EMEG	No
2-Chloroethylvinyl ether	0:12				No
2,2-Dichloropropane	0:47				No
2,4,5-Trichlorophenol	1:734	0.590	5000	RMEG	No
2,4,6-Trichlorophenol	1:734	0.577	60	CREG	No
2,4-Dichlorophenol	1:734	0.340	200	RMEG	No
2,4-Dimethylphenol	8:779	0.331	1000	RMEG	No
2,4-Dinitrophenol	2:726	1.100	100	RMEG	No
2,4-Dinitrotoluene	1:734	0.564	100	EMEG	No
2,6-Dinitrotoluene	1:734	0.564	80	MTCA	No
2-Chloronaphthalene	1:734	0.110	4000	RMEG	No
2-Chlorophenol	1:734	0.120	300	RMEG	No
2-Chlorotoluene	0:47				No
2-Hexanone	0:61				No
2-Methylnaphthalene	117:811	0.130	NA	NA	No
2-Methylphenol	10:811	0.220	3100	Region 9	No
2-Nitroaniline	1:726	0.590	1.7	Region 9	No
2-Nitrophenol	1:734	0.570	NA	NA	No
2,4'-DDD	0:3				No
2,4'-DDE	0:3				No
2,4'-DDT	0:3				No
2-Nitropropane	0:47				No
3-Nitroaniline	0:688				No
3,3'-Dichlorobenzidine	2:668	0.590	2	CREG	No
4-Bromophenyl phenyl ether	1:734	0.120	NA	NA	No
4-Chloro-3-methylphenol	1:726	0.240	NA	NA	No
4,4'-DDD	20:219	0.020	3	CREG	No
4,4'-DDE	40:219	0.012	2	CREG	No
4,4'-DDT	16:219	0.020	2	CREG	No
4-Chloroaniline	3:649	0.356	200	RMEG	No
4-Chlorophenyl phenyl ether	1:734	0.120	NA	NA	No
4-Chlorotoluene	0:47				No
4-Methylphenol	50:473	0.400	310	Region 9	No
4-Nitroaniline	2:672	0.590	NA	NA	No
4-Nitrophenol	1:726	0.570	NA	NA	No
Acenaphthene	317:811	0.255	3000	RMEG	No
Acenaphthylene	82:811	0.110	NA	NA	No
Acetone	5:61	0.162	5000	RMEG	No
Aldrin	2:215	0.005	2	RMEG	No
Allyl Chloride	0:47				^No
Aluminum	684:691	29000	76000	Region 9	No
Ammonia	81:81	74	20000	Int. EMEG	No
Aniline	2:126	0.110	100	RMEG	No
Anthracene	560:812	0.420	20000	RMEG	No
Antimony	163:647	13	20	RMEG	No
Aroclor-1016	3:984	0.080	4	RMEG	No
Aroclor-1221	2:781	0.054	0.220	Region 9	No
Aroclor-1232	2:781	0.030	0.220	Region 9	No
Aroclor-1242	136:984	0.319	0.220	Region 9	Total PCBs
Aroclor-1248	208:983	0.869	0.220	Region 9	Total PCBs
Aroclor-1254	731:987	1.800	1	EMEG	Total PCBs
Aroclor-1260	745:986	2.400	0.220	Region 9	Total PCBs
Arsenic	789:887	30	20	EMEG	Yes
Barium	609:609	153	4000	RMEG	No
Benzene	1:61	0.006	10	CREG	No
Benzidine	2:16	1.350	0.003	CREG	Too Few
Benzo(a)anthracene + Chrysene	735:813	1.100	0.137	MTCA	cPAHs
Benzo(a)pyrene	719:812	1.045	0.100	CREG	cPAHs
Benzo(b)fluoranthene	701:784	1.600	0.137	MTCA	cPAHs
Benzo(g,h,i)perylene	684:812	0.570	NA	NA	No
Benzo(k)fluoranthene	674:784	0.910	0.137	MTCA	cPAHs
Benzoic acid	71:786	1.100	200000	RMEG	No
Benzyl alcohol	14:799	0.511	24000	MTCA	No
Beryllium	672:708	0.6	50	EMEG	No
Biphenyl	2:2	0.030	3000	RMEG	No
bis(2-chloroethyl)ether	0:734				No
bis(2-chloroisopropyl)ether	0:734				No
Bis(2-chloroethoxy) methane	2:734	0.120	NA	NA	No
bis(2-ethylhexyl)phthalate	701:820	4.010	71.4	MTCA	No
Bromobenzene	0:47				No
Bromochloromethane	0:47				No
Bromodichloromethane	0:61				No
Bromoform	0:61				No
Bromomethane	0:61				No
Butyl benzyl phthalate	437:818	0.360	10000	RMEG	No
Cadmium	617:869	4	10	EMEG	No
Carbazole	377:734	0.320	50	MTCA	No
Carbon disulfide	18:61	0.018	5000	RMEG	No
Carbon tetrachloride	0:61				No
Chlordane	12:126	0.040	2	CREG	No
alpha-Chlordane	1:89	0.025			No
trans-Chlordane	4:85	0.025			No
Chlorobenzene	0:61				No
Chloroethane	0:61				No
Chloroform	1:61	0.006	500	EMEG	No
Chloromethane	0:61				No
Chromium	830:845	70	210	Region 9	No
Chromium VI	1:20	15	200	RMEG	No
Chrysene	759:813	1.540	0.137	MTCA	cPAHs
cis-1,2-Dichloroethene	1:59	0.004	NA	NA	No
cis-1,3-Dichloropropene	0:61				No
Cobalt	459:474	14	4700	Region 9	No
Copper	876:887	147	2960	MTCA	No
Coprostanol	84:227	2.4	NA	NA	No
Cyanide	1:25	49	1000	RMEG	No
Cymene	3:47	0.004	NA	NA	No
Dibenzo(a,h)anthracene	413:812	0.205	0.137	MTCA	cPAHs
Dibenzofuran	240:810	0.150	290	Region 9	No
Dibromochloromethane	0:61				No
Dibutyltin	88:139	0.051	NA	NA	No
Dichloromethane	1:61	0.020	NA	NA	No
Dichlorodifluoromethane	0:9				No
Dieldrin	21:215	0.010	0.04	CREG	No
Diethyl ether	0:47				No
Diethyl phthalate	9:818	0.120	40000	RMEG	No
Dimethyl phthalate	132:818	0.120	80000	MTCA	No
Di�butyl phthalate	251:818	0.282	5000	RMEG	No
Di�octyl phthalate	50:819	0.130	20000	int EMEG	No
Dioxin/furan TCDD toxicity equivalent	29:29	0.0001	0.00005	EMEG	Explain
Endosulfan	0:92				No
Endosulfan sulfate	2:158	0.010			No
Endrin	0:175				No
Endrin aldehyde	5:158	0.020	NA	NA	No
Endrin ketone	2:85	0.020	NA	NA	No
Ethyl Methacrylate	0:47				No
Ethylbenzene	1:95	0.009	5000	RMEG	No
Ethylene bromide	0:47				No
Fluoranthene	778:813	2.900	2000	RMEG	No
Fluorene	389:811	0.245	2000	RMEG	No
Gasoline	0:24				No
Heavy oil	5:13	4580	200	MTCA	Explain
Heptachlor	4:214	0.005	0.200	CREG	No
Heptachlor epoxide	3:176	0.006	0.08	CREG	No
Hexachlorobenzene	50:806	0.110	0.4	CREG	No
Hexachlorobutadiene	1:811	0.220	9	CREG	No
alpha-Hexachlorocyclohexane	0:175				No
beta-Hexachlorocyclohexane	1:175	0.005	0.4	CREG	No
delta-Hexachlorocyclohexane	1:95	0.004	NA	NA	No
gamma-BHC	5:210	0.005	20	RMEG	No
Hexachlorocyclopentadiene	2:618	0.590	300	RMEG	No
Hexachloroethane	1:793	0.220	50	CREG	No
Indeno(1,2,3-cd)pyrene	688:813	0.620	0.137	MTCA	cPAHs
Iron	689:689	39520	23000	Region 9	Explain
Isophorone	0:733				No
Isopropylbenzene	0:47				No
Lead	876:887	260	400	Region 9	No
Magnesium	636:636	9800	NA	NA	No
Manganese	652:652	619	3000	Region 9	No
Mercury	748:875	0.6	24	MTCA	Fish Pathway
Methacrylonitrile	47:47	0.018	5	RMEG	No
Methoxychlor	6:175	0.016	300	RMEG	No
Methyl Acrylate	0:47				No
Methyl ethyl ketone	18:61	0.024	48000	MTCA	No
Methyl-t-butyl ether	0:47				No
Methyl iodide	0:47				No
Methyl methacrylate	0:47				No
Methylmercury	59:59	0.002	5	RMEG	No
Methylene bromide	0:47				No
Mirex	0:3				No
Molybdenum	37:156	6	300	RMEG	No
Naphthalene	129:811	0.130	1000	RMEG	No
Nickel	856:873	37	1000	RMEG	No
Nitrobenzene	0:734				No
Nitrosodimethylamine	0:216				No
Nitrosodipropylamine	0:734				No
Nitrosodiphenylamine	20:811	0.120	100	CREG	No
Octadecanal	2:2	1.1	NA	NA	No
Pentachloroethane	0:47				No
Pentachlorophenol	13:759	0.590	6	CREG	No
Phenanthrene	741:813	1.5	NA	NA	No
Phenol	229:811	0.300	30000	RMEG	No
Polychlorinated Biphenyl Dioxin-like Congeners		0.00009	0.000007	MTCA	Explain
PCB 77	20:662
PCB 81	0:333
PCB 105	470:657
PCB 114	9:333
PCB 118	582:661
PCB 123	0:333
PCB 126	16:661
PCB 156	253:659
PCB 157	76:657
PCB 167	56:333
PCB 169	0:659
PCB 189	30:659
Propylbenzene	0:47				No
Pyrene	768:813	2.600	2000	RMEG	No
Selenium	303:697	20	300	EMEG	No
Silver	586:869	2	300	RMEG	No
Styrene	0:61				No
Tetrabutyltin	11:153	0.020	NA	NA	No
Tetrachloroethene	3:90	0.009	19.6	MTCA	No
Thallium	355:707	36	5.2	Region 9	Explain
Tin	229:351	15	48000	MTCA	No
Toluene	6:61	0.006	10000	RMEG	No
Total Petroleum Hydrocarbons	65:73	4300
Total Polynuclear Aromatic Hydrocarbons	599:613	16	NA	NA	No
Total Polychlorinated Biphenyls	1194:1325	4.446	0.4	CREG	Yes
Total Tetrachlorodibenzo-p-dioxins	23:30	0.00002	0.000007	MTCA	Explain
Total of 6 isomers: pp,op-DDT,-DDD,-DDE	83:213	0.080	NA	NA	No
Toxaphene	0:175				No
TPH - Diesel	6:31	1415	200	MTCA	Explain
TPH - Gasoline Range	0:8				No
TPH - Heavy Fuel Oil Range	2:8	328	200	MTCA	Too Few
Tributyltin	130:154	0.312	20	RMEG	Fish Pathway
Trichloroethene	4:95	0.010	91	MTCA	No
Trichlorofluoromethane	0:59				No
Vanadium	474:474	81	560	MTCA	No
Vinyl acetate	0:12				^No
Vinyl chloride	0:61				No
Ortho-xylene	1:56	0.004	10000	int EMEG	No
Total xylenes	0:43				No
m,p-Xylene	1:56	1	10000	int EMEG	No
Zinc	872:886	360	20000	EMEG	No