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The Lower Duwamish Waterway (LDW) study area is located in King County, Washington, andruns through three jurisdictions: Seattle, King County, and Tukwila. The LDW is a section of theDuwamish River that extends approximately 6 miles from the southern tip of Harbor Island southto Turning Basin #3. On September 13, 2001, the site was listed on the National Priorities List(NPL) by the U.S. Environmental Protection Agency (EPA) .

The site is encompassed by industrial and commercial operations, past and present, that includecargo handling and storage, marine construction, boat manufacturing, marina operations, paperand metal fabrication, food processing, and airplane parts manufacturing. In addition, there areover 100 storm drains, combined sewer overflows (CSOs), and other miscellaneous outfalls. [1] These activities have resulted in considerable chemical releases into the LDW over the past 100years. Contaminant sources include spills and leaks from industrial facilities, industrialoperations, waste disposal practices, surface water runoff, storm drain discharge, groundwater discharge, erosion of contaminated soils, atmospheric deposition of industrial air emissions, andCSOs.

DOH gathered a number of community health concerns, many of which related to consumptionof fish and other activities involving the river. Common concerns expressed during communityinterviews and outreach activities related to the safety of consuming salmon harvested from theLDW, seafood consumed from local markets, and a lack of information warning againstconsumption of seafood harvested from the LDW.

The two major pathways of exposure for residents using the LDW are consumption of fish andshellfish and contact with sediment during recreational activities. The main contaminants ofconcern are polychlorinated biphenyls (PCBs) and mercury, but also include arsenic andpolycyclic aromatic hydrocarbons (PAHs) among others. Exposure to contaminated seafood andsediment in the LDW was evaluated under various scenarios. Each scenario contains differentassumptions that estimate the amount of chemical to which a person might be exposed either byeating fish or through direct contact with sediment. This dose can then be compared with toxicity data to help determine if an exposure is a health hazard.


People who frequently eat resident (nonanadromous) fish and crab caught in the LDW androckfish from Elliot Bay near Harbor Island may be at some risk for adverse health effects. Theprimary health concern is the potential for adverse effects on the development of childrenexposed in the womb. Exposure of the fetus to mercury and PCBs has been shown to impairlearning and behavior during childhood. Although a consumption advisory for shellfish,bottomfish, and crab currently exists at urban areas along the King County shoreline, includingElliott Bay and the Lower Duwamish Waterway, the advisory has not been well communicated topotentially impacted populations.

  • Data regarding contaminants in LDW salmon indicate that PCB levels are lower thanin resident fish and similar to those found in salmon from other parts of PugetSound. Salmon also contain high levels of omega-3 fatty acids which protect againstheart disease and make salmon a desirable fish to eat. However, if consumed at highrates, contaminants in salmon can also increase adverse health risks to thedeveloping fetus. Exposure to PCBs in salmon and other fish can be reduced throughproper preparation and cooking.

  • Rockfish caught in Elliot Bay near Harbor Island contain elevated levels of PCBsand mercury. Although the presence of rockfish in the LDW is questionable, they areincluded in the health assessment because area residents may fish both water bodies.

  • Crab samples also indicate elevated levels of PCBs and mercury. Although theamount of crab consumption along the river is not known, people have beenwitnessed catching crabs in the Duwamish, and therefore, advice on the risk of crabconsumption from the LDW is necessary. Furthermore, the hepatopancreas in crabscan contain very high levels of PCBs. A study of Asian Pacific Islander seafoodconsumption revealed that a number of people eat the entire crab including thehepatopancreas.

An indeterminate health hazard exists for people who eat shellfish from the LDW. It is not clearthat the LDW can support a significant shellfish harvest. Mussels were the only species ofshellfish that were sampled from the LDW, and metals, PAHs, and PCBs were detected in somesamples. Other types of shellfish may accumulate contaminants at different rates, but it is notknown what species exist or their quantity. Consumption of significant quantities of shellfishmay be of concern, and the DOH Food Safety and Shellfish Programs advise against harvestingshellfish from the King County shoreline (including the LDW), except for Vashon-Maury Island(Figure 8), due to general chemical and biological contamination.

Exposure to sediments in the LDW represents no apparent public health hazard. Althoughsediments in the LDW have been contaminated, direct contact with sediment through recreationaland occupational activities is not expected to result in adverse health effects. The contribution ofthis pathway is minimal relative to the overall exposure of residents who also eat LDW fish.

Exposure to chemical contaminants in surface water while swimming represents no apparentpublic health hazard. The King County Water Quality Assessment concluded that there is littlerisk to swimmers associated with chemical contaminants in LDW water. Outreach efforts havenot indicated that swimming is a common practice, but it is important to note that Public HealthSeattle and King County (PH-SKC) has a current advisory against swimming near any of the ninecombined sewer overflows (CSOs) in the LDW. This advisory is based on potential exposure to pathogens associated with sporadic releases of raw sewage into the river.


Resident fish including sole, flounder, perch, and crab should be limited to one meal per monthespecially for pregnant women or those considering pregnancy. Consumption of Rockfish fromElliot Bay near Harbor Island should be avoided. Finfish consumers should eat skinless, cookedfillets and avoid consuming other parts of the fish, particularly the liver. The hepatopancreas ofcrabs should not be eaten due to the tendency of this organ to concentrate PCBs. People that eat alot of fish as part of their regular diet should avoid eating LDW resident fish altogether.

Salmon are the preferred species of fish to eat from the LDW because they are relatively low incontaminants, and have high levels of beneficial fatty acids. Salmon should continue to be eaten,however, pregnant women or those considering pregnancy should be aware that even salmonhave levels of contaminants that can be detrimental to the developing fetus if consumed on adaily basis. DOH is currently evaluating PCB exposure from consumption of salmon caughtthroughout Puget Sound, and more specific advice about salmon may be forthcoming.

Further evaluation as to the extent of contamination in some fish, shellfish and crab species isneeded to adequately assess exposure from consumption of these species caught in the LDW.However, DOH Food Safety and Shellfish Programs advise against harvesting shellfish from the King County shoreline, except for Vashon-Maury Island (Figure 8), due to general chemical and biological contamination.

  • Additional sampling of some species is necessary in order to adequately assess thecurrent advisory and evaluate the need for a more specific advisory that could includeconsumption limits.

  • Any additional environmental data that is collected will be evaluated by DOH.

Signs communicating the fish/shellfish advisories should be placed at fishing access locations.Additional advisory signs with translation in several languages including new Spanish andRussian translations will be posted at several areas along the river. Educational/interpretive signswill be placed at three popular fishing locations: Spokane Street Bridge, Terminal 105, and Herring House Park.

Educational information materials should be provided to populations potentially impacted byLDW contamination. This information should communicate the existing health advisory, andcommunicate the findings of this public health assessment.

  • DOH has provided, and will continue to provide health information materials, follow-up health education activities, and present results of this health assessment to thecommunity. Groups previously contacted for their community health concerns will bethe primary audience.

The effectiveness of advisory signs and communications should be assessed over time in order to determine if the message is reaching and staying with the affected community.


This public health assessment was prepared for the Lower Duwamish Waterway (LDW) site bythe Washington State Department of Health (DOH) under a cooperative agreement with theAgency for Toxic Substances and Disease Registry (ATSDR). This health assessment ismandated by the Comprehensive Environmental Response, Compensation, and Liability Act(CERCLA) of 1980. The LDW site was proposed for listing on the National Priorities List (NPL)on December 1, 2000, in accordance with Section 105 of CERCLA, 42 U.S.C. 9605. [2] ATSDR isrequired to conduct a public health assessment for all hazardous waste sites proposed forinclusion on the National Priorities List. On September 13, 2001, the LDW site was officiallylisted on the NPL by the U.S. Environmental Protection Agency (EPA). The NPL is EPA's list ofthe Nation's most contaminated hazardous waste sites, also known as Superfund sites.

The purpose of this assessment is to determine whether the site poses a public health threat aswell as make recommendations and take appropriate actions based on that determination. While arisk assessment conducted under EPA's Remedial Investigation/Feasibility Study (RI/FS) processis used to support the selection of a remedial measure at a site, the Public Health Assessment(PHA) is a mechanism used to provide the community with information on the public healthimplications of a specific site, identifying those populations for which further health actions or studies are needed. [3] Therefore, different assumptions and methods may be used in these studiesreflecting their different purposes.

A. Site Description and History

The LDW site is located in King County, Washington on the south shore of Elliott Bay andconsists of nearly 6 miles of the Duwamish River beginning at the south end of Harbor Islandand extending south, just beyond Turning Basin #3. The LDW has served as Seattle's majorindustrial corridor since it was first created by widening and straightening of the DuwamishRiver (and formation of Harbor Island) by the U.S. Army Corps of Engineers from 1913 to1920. [4] Over 90 years of intense industrial use has resulted in extensive contamination tosediments and some fish species.

Past and current commercial and industrial activities identified at the site include cargo handlingand storage, marine construction, boat manufacturing, marina operations, paper and metalfabrication, food processing, and airplane parts manufacturing. The site includes over 15National Pollutant Discharge Elimination System (NPDES) permit holders and over 100properties that are listed on Ecology's Confirmed and Suspected Contaminated sites. [5] In addition,there are over 100 storm drains, combined sewer overflows (CSOs), and other miscellaneousoutfalls.[1] These activities have resulted in considerable chemical releases into the LDW over thepast 90 years. Sources of contamination include spills and leaks from industrial facilities,industrial operations, waste disposal practices, surface water runoff, storm drain discharge,groundwater discharge, erosion of contaminated soils, atmospheric deposition of industrial airemissions, and combined sewer overflows. Nine CSOs within the LDW study area dischargeover 300 million gallons of storm water. Raw sewage is released through these CSOs when wastewater treatment plants reach capacity during periods of heavy rain. [6]

The LDW site is currently being co-managed by EPA and the Washington State Department ofEcology (Ecology) under federal CERCLA and state Model Toxics Control Act (MTCA)mandate. EPA is coordinating site investigation activities while Ecology provides oversight onupland source control activities. Four potentially liable parties collectively known as the LowerDuwamish Waterway Group (LDWG) including the Port of Seattle, King County, City of Seattleand the Boeing Company, are working with EPA and Ecology to investigate the nature andextent of chemical contamination in LDW sediments and evaluate cleanup alternatives.

The Duwamish River discharges into Elliott Bay, a deep saltwater port within Puget Sound. Tidalinfluence extends as far as 13 miles upstream. Surface water in the Duwamish River is primarilyfresh or brackish, while deeper water contains more salt. A salt wedge has been documented 10miles upstream from Elliot Bay. The Duwamish River is approximately 200 feet wide and 30 feetdeep below the First Avenue South Bridge, and 150 feet wide and 15-20 feet deep upstream of the bridge. The river is more shallow upstream due to less frequent dredging activities.

Harbor Island (another Superfund site listed on the NPL in 1983) is located at the mouth of theDuwamish River, just north of the northern boundary of the LDW. Harbor Island has beenextensively utilized for commercial and industrial activities including ocean and rail transportoperations, bulk fuel storage and transfer, secondary lead smelting, fabrication, shipbuilding, andmetal plating. Contaminant sources on Harbor Island included storm drains, groundwaterseepage , non-point discharges, atmospheric deposition, direct discharge of waste, and historicaldisposal practices.

Several environmental investigations have been conducted within the LDW study area.Environmental sampling has included analysis of fish, shellfish, crab and sediments. Waterquality sampling has also been conducted to evaluate municipal, commercial, and industrialdischarges into the LDW. [7]

The Remedial Investigation (RI) for the LDW site is being conducted in two phases. The objectives of the first phase are to evaluate, compile, and summarize existing data collected during historical environmental investigations; use existing data to conduct a scoping-phase human health and ecological risk assessment; identify locations within the LDW where early cleanup actions may be suitable; identify data gaps and prepare a work plan to complete the RI. [8] To date, the LDWG has prepared an initial RI and has identified several sites along the LDW that have been slated for early cleanup. The objectives of the second phase are to conduct additional studies to fill data gaps, prepare a baseline ecological and human health risk assessment, and estimate residual health risk associated with completed or planned early cleanup actions.

A large data set exists for sediment chemistry within the LDW (over 1200 surface sedimentsamples); however sediment samples near public access points are limited. Existing dataregarding contaminant concentrations in fish, shellfish, and crab tissue are limited. The scoping-phase human health risk assessment for the LDW is based upon existing environmental data andis intended to determine if contaminants in sediment from the LDW represent a human healthhazard due to seafood consumption, dermal contact, and incidental ingestion of contaminatedsediments. Data gaps identified in the scoping-phase human health risk assessment will be filledprior to conducting the baseline human health risk assessment during the second phase of the RI. [9]

B. Site Visits

DOH representatives conducted a number of site visits in the summer of 2001 and the spring and summer of 2002 in conjunction with various representatives of federal, state and local environmental agencies, coalitions, environmental groups, and the general public. Site visits included boat tours, walking portions of the shoreline and visiting area neighborhoods. Cursory inspection of the area surrounding the site was also conducted by driving around the entire perimeter in an automobile.

During boat tours, a number of observations were made and site photos were collected using a digital camera (Appendix B). Observations focused on potential human access points along the LDW shoreline including boat launches, fishing piers or areas that would accommodate fishing or other recreational activities. During the site visits, it was noted that a number of streets end at the shoreline providing access to the river.

Several people were observed fishing and walking the shoreline at Duwamish River Park, and on one occasion, people were observed swimming in the LDW. Commercial fishing nets set for salmon were seen north of South Park Marina. Many shoreline areas along the LDW were easily accessible and individuals were observed walking, jogging, and picnicking along trails that run parallel to the waterway.

C. Demographics, Land Use and Natural Resources Use


The City of Seattle has a population of 563,374, and the entire population of King County is 1,737,034. These population figures are based upon 2000 census data and represent an increase of 9.1 and 15.2 % over the 1990 census population numbers.

The LDW study area extends through both the South Park and Georgetown neighborhoods of south Seattle. The South Park neighborhood is defined as census tract 112, and Georgetown is defined as census tract 109. [10] The South Park and Georgetown neighborhoods are both located within the postal zip code area 98108, and have a combined population of approximately 4,900. Population in Georgetown (Census tract 109) has decreased slightly since 1990, while South Park's (tract 112) population has increased by nearly 32 %. Table 1 shows the changes in population between 1990 and 2000.

Table 1.

Comparison between 1990 and 2000 population for Census Tracts 109 (Georgetown) and 112 (South Park) King County, Seattle, Washington. [11]
Census Tract 109 (1990 Census) Census Tract 109
(2000 Census)
Census Tract 112 (1990 Census) Census Tract 112 (2000 Census)
Total: 1,238 1,181 2,809 3,717
White 856 724 1,874 1,626
Black or African American 102 78 238 312
Hispanic or Latino 152 174 420 1,379
American Indian and Alaska Native 79 30 96 74
Asian 121 163 365 524
Native Hawaiian and Other Pacific Islander N/A 19 N/A 51
Some other race 80 98 236 916
Multiracial N/A 69 N/A 214

Land Use

Zoning along the LDW study area includes residential, commercial, residential/commercial, neighborhood commercial, and industrial. Shoreline zoning includes conservancy recreation, conservancy preservation, and urban industrial use. Upland areas adjacent to the LDW are heavily industrial and commercial, but also support residential use.

Although the majority of land use and zoning in the LDW corridor is industrial, there are two mixed residential/commercial neighborhoods adjacent to the study area. [10] The South Park neighborhood is located in the southern city limits of the City of Seattle and borders the west side of the LDW. [10] The Georgetown neighborhood is located east of the LDW and is separated from the site by several commercial facilities between the waterway and East Marginal Way South. [10]

Natural Resource Use

The LDW is a major shipping route for containerized and bulk cargo. A portion of the LDW site is maintained by the U.S. Army Corps of Engineers as a federal navigation channel supporting intensive marine traffic.

The Muckleshoot Tribe commercially harvest salmon (chinook, coho, chum, winter and summer steelhead) from the LDW. The LDW also abuts the usual and accustomed (U & A) fishing area for the Suquamish Tribe. In addition, recreational fishing for salmon and bottomfish is prevalent within the area, and subsistence fish consumption among various populations has also been reported. [12] A number of water related recreational activities occur in the LDW including swimming, kayaking, wading, and scuba diving.

Approximately 10 million juvenile salmon migrate through the LDW annually. A number of studies conducted by the National Marine Fisheries Service (NMFS) indicate that juvenile salmon from the LDW exhibit reduced growth and immune system function. In contrast, a recent study concluded that chronic dietary exposure to PCBs did not have an effect on growth and disease resistance in juvenile chinook salmon in conditions relevant to the LDW. [13] Several habitat restoration activities have occurred at the LDW site including the recent Herrings House Park restoration project (17 acre wetland) that provides refuge for salmon migrating downstream through the LDW. The LDW serves as a migratory route and transition zone for Pacific salmon. Chinook salmon are federally listed as a threatened species and use the LDW during a critical stage of migration.


Community members expressed a number of health concerns relating to the LDW site. Specific health concerns are outlined and individually addressed in the Community Health Concerns Evaluation section of this public health assessment. The following is a discussion of strategies used to connect with ethnically diverse communities surrounding the LDW and the health concerns that were gathered. It is organized chronologically outlining activities and community groups that were contacted by DOH during community outreach activities.


Community outreach and education is an essential component of the public health assessment process. The community outreach educator's initial responsibility is to contact people who may be exposed to contaminants in the river, find out how they are being exposed, and if they have any health concerns. Exposure means a person is eating, breathing, or drinking contaminants, or absorbing them through their skin.

Initial outreach efforts dispelled the notion that it was common knowledge that the LDW was polluted, and that there is no harvest or consumption of seafood from the LDW. One South Park activist repeatedly insisted that people were consuming seafood from the LDW and that these people were most likely from Pacific Islander or Asian immigrant and refugee communities. Populations who rely on the LDW as a primary source of food prefer to remain anonymous. They often fish without a license to provide food for their families and many have a deep distrust of government officials. Therefore, the primary community outreach strategy emphasized compassion followed by education. DOH made over two hundred phone calls to community organizations to find key community leaders from Asian/Pacific Islander populations who were willing to assist with coordination and communication activities. The key to reaching these populations was to allow community leaders to offer their own strategies for connecting with their people, and then incorporating and implementing their ideas.

Outreach Strategy

Connecting with culturally diverse, non-English speaking communities requires outreach that goes beyond traditional methods such as meetings sponsored by government agencies, informational mailings, and press releases. Meeting with community groups on their own terms demonstrated sincerity and built trust. Arranging to meet community members at meal sites (meals organized at community centers for seniors or other community members), where many congregate weekly to socialize and have lunch, is an excellent way to initiate communication. Some communities participate in monthly evening meetings at an individual's home or at a neighborhood community center. Focus groups hosted by a community leader and a local interpreter are also effective. Such interaction with the community builds credibility that is essential for healthy interactive relationships and establishes the foundation for health education activities.

DOH conducted an extensive community outreach campaign in conjunction with the preparation of this public health assessment. Various outreach approaches included meeting groups at meal sites, arranging focus groups through Public Health-Seattle & King County (PH-SKC), attending community events, participating in river tours, and talking one-on-one with community leaders and community representatives. Health concerns and feedback for future outreach activities were gathered from Cambodian, Vietnamese, Filipino, Hmong, Laotian, Tongan, Hispanic, Native American and white members of the South Park and Georgetown neighborhood communities. Concerns and opinions were also collected from environmental groups involved in river restoration, state representatives, business leaders, and a Washington State Fish and Wildlife Conservation officer. A complete description of community involvement activities is given below.

One-on-One Community Interviews

During March and April of 2001, representatives from DOH, EPA and Ecology began conducting one-on-one interviews with community members, community leaders, state representatives, business leaders, environmentalists, tribal members, and community activists. Individuals that were interviewed had either indicated an interest by responding to a request from EPA, or were identified as interviewees due to past involvement with the LDW site. During this time period, over 35 community interviews were conducted at EPA or at locations within the Duwamish corridor. In some cases interviews were conducted via conference call. A set of questions were administered to interviewees and responses to questions were summarized and listed in EPA's community involvement plan.

Concerns expressed included:

  • Health hazards of fish consumption (particularly salmon).
  • Respiratory problems.
  • Reaching the Spanish-speaking neighbors.
  • Health hazards of dermal contact with sediments.
  • Health risks during cleanup work parties.
  • Staff turnover within government agencies.
  • Health hazards of fish consumption among Southeast Asian and Native American populations.
  • Subsistence fishing in the river.
  • Litigation and delays in cleanup.
  • Health hazards of children playing in the sediments and the water.
  • Cumulative effects of exposure to contaminants from different sources in the community.
  • Quality of life and mortality rates in the community.
  • Connections between contaminants and cancer and lung disease.
  • Health hazards to unborn children and women of childbearing age.
  • The safety of fish sold in markets.
  • Data are not being shared, communicated, or made publicly available.

Public Availability Session

On May 24, 2001, DOH organized an availability session at Concord Elementary School located in the South Park Neighborhood to gather community health concerns. Over six-hundred invitations were mailed to local residents and businesses. There was considerable agency participation from DOH, PH-SKC, EPA, and Ecology. However, the session was not attended by any nonbusiness members of the community. As a result, DOH used other methods to communicate with populations potentially impacted by contamination within the LDW site.

Hispanic Community

A public health educator from PH-SKC organized two Hispanic focus groups through the SeaMar Community Health Center to explore how the Hispanic community may be using the LDW. Both meetings were held at the SeaMar Community Care Center. Many of the group participants live within and around the South Park neighborhood and utilize SeaMar for personal and family medical care. The initial focus group was held August 14, 2001, and the second group was held the following evening. A combined total of 17 individuals participated in the focus groups. Several participants indicated they walk along the shore of the LDW and picnic at a park located at the shoreline of the LDW. None of the participants in either focus group fish in the LDW. However, there were reports of "older gentlemen" frequently fishing from the South Park bridge and Boeing bridge. No health concerns related directly to LDW contamination, but participants were concerned about drinking water quality. [14]

On September 20, 2001, the South Park Neighborhood Association (formerly the South Park Crime Council) held their first Spanish-speaking meeting in the thirty years of the Association's existence. Representatives from DOH and EPA attended this meeting. DOH distributed maps and initiated a discussion about fishing, recreational habits and health concerns. The representative from EPA outlined her role in the site cleanup process and served as an interpreter. The meeting was held in a beauty parlor on the first floor of a private residence in the heart of the South Park neighborhood.

Thirty adults and several children, in a standing-room only crowd, participated with a high level of interest. Participants expressed frustration that, as a poor community, they feel they are being ignored by government agencies. Meeting participants indicated they were not aware of any contamination problems and do not fish in the LDW. There was concern about children playing in sediments at parks along the river and participants indicated an interest in assisting with posting signs in local parks. Participants indicated that signs need to communicate in both Spanish and English. Because local parks are frequently used, there was interest in receiving further environmental health education. Language was identified as a barrier to communication between agencies and the community.

On October 24, 2001, DOH met with El Planeta, an Hispanic youth group in the South Park neighborhood led by a representative of the Environmental Coalition of South Seattle (ECOSS). Seven teenagers and four adults participated. An overview of the LDW and potential adverse impacts on human health were discussed, as well as fishing habits of individuals within the neighborhood. The participants stated that they do not fish in the river, but they frequently observe other people (non-Hispanic) fishing in the river. Site location maps were distributed, a shellfish filter-feeding demonstration was provided, examples of shells from shellfish native to the LDW and Elliott Bay were shared, pictures of bottomfish were displayed and discussed, and an example of an advisory sign was presented. The sign uses the word "bottomfish" and adults explained that there is not a word for "bottomfish" in the Spanish language. Teens each received a handout with questions that will be used to canvass their neighborhood as part of an El Planeta environmental education project.

Asian/Pacific Islander Communities

The Asian/Pacific Islander (API) communities within the Duwamish corridor are very diverse, although many share a traditional diet high in fish and shellfish. API groups expressed similar concerns and are likely to be among high-end consumers of seafood harvested from the LDW. DOH learned from local community leaders and Washington Department of Fish and Wildlife officials that API community members may be subsistence fishing without a license, so they may be reluctant to admit that they harvest seafood from the LDW. It was difficult to identify API community leaders within the boundaries of the South Park neighborhood. Therefore, it was necessary to expand into surrounding neighborhoods with community centers that serve the API target populations. As a result of this strategy, DOH learned that many groups that fish in the Duwamish river do not necessarily live in neighborhoods adjacent to the river. Additionally, as "word of mouth" is often a very effective way to communicate in immigrant communities, participants were asked to spread the word regarding the existing Duwamish fish advisory to their families and friends. Common themes expressed by community members included concern about safety of consuming salmon harvested from the LDW and how to be certain that seafood purchased in markets is safe to eat. The second concern is addressed in the Community Health Concerns Evaluation section (question 2) of this health assessment.

PH-SKC organized two Vietnamese focus groups to explore how the Vietnamese community uses the LDW. A Vietnamese outreach worker was retained to assemble both focus groups. One woman, her husband, and a colleague who are very active and respected within the Vietnamese community assisted. These individuals were able to use personal contacts, existing clinic lists, and door-to-door requests to solicit participation in focus groups. The first focus group was held on August 9, 2001. There were eleven participants, six men and five women, from the vicinity of the High Point Housing community in west Seattle. Several of the women had young children and childcare was provided. The second focus group, held on August 11, 2001, consisted of four women and five men. Most of the men were senior citizens while the women were younger. All but one of the participants lived in the Rainier Vista Housing community. [14]

All participants in both groups were aware of the LDW, several had fished there, and all were aware of people who either fish or consume fish harvested from the LDW. Crab and flounder are some of the species consumed from the waterway. One participant indicated that a relative fishes and eats fish harvested from the LDW daily. A single person indicated that he eats fish and/or shellfish from the LDW once a week and another individual consumes seafood from the area about once a month. People said they like to eat fish heads, stomach, and the eggs. One participant's nephew fishes and gives the fish away to family members. Another participant knows someone who fishes in the LDW and sells to a local fish market. One woman indicated she recently consumed a crab (which she often does) from the LDW and described the crab as "muddy and oily" even though she cleaned it well. She said the flesh was bitter and that she later became sick to her stomach but did not seek medical attention. Vietnamese participants were very concerned that they had no previous knowledge of LDW pollution. Both groups agreed that if there is a concern about the river, the information needs to shared with the community. Neither group was aware of signs communicating any type of a warning. [14]

On September 27, 2001, the Pacific Asian Empowerment Program (PAEP) in Seattle arranged for DOH to provide a presentation with questions and answers at a senior citizen meal site in the local Filipino Community Center. Approximately fifty people attended, including several community leaders. All participants spoke English, therefore no translators were necessary. Each participant received a DOH booklet entitled "Public Shellfish Sites of Puget Sound" as well as a shellfish-shaped magnet printed with the DOH 1-800 shellfish hotline telephone number and web-site address. This group was well-educated and organized. DOH received a very warm reception from them, and everyone indicated that they eat shellfish and seafood as it represents a large part of their original island culture. Some individuals indicated consumption of fish heads, livers, and other organs. Three men admitted they fish within the LDW and wanted to know if it was safe to consume salmon from the LDW. Questions arose relating to the safety of consuming seafood from local markets, and what type of fish, if any, are safe for consumption. This group was very interested in signs being posted along the LDW shoreline regarding the existing health advisory and were very interested in follow-up environmental health education.

On September 28, 2001, the PAEP arranged for a DOH presentation, with questions and answers, to the Hmong and Laotian community at a meal-site at the Brighton Presbyterian Church on 51st Avenue. Two translators from the community provided interpretation in the Laotian and Hmong languages. About 35 people joined in the discussion, which included a shellfish filter-feeding demonstration. The church has a Vietnamese pastor and participants were primarily elderly, but there were several younger adults and some small children in attendance.

The Hmong were a mountain-dwelling people in their homeland and the Laotians originally lived in land-locked communities. Many people did not know where the LDW was located and were not sure if they had ever been there. One man reported that he has fished in the LDW and a few people mentioned that they fished in Lake Washington. The immediate question was why signs were not posted within the LDW if there is a pollution problem. This group does eat fish and shellfish from the LDW but primarily purchases seafood from local markets. The other immediate question related to whether or not fish and shellfish at local markets were safe. This population agreed to spread the word within their communities regarding the existing health advisory for the LDW. There were no human health concerns expressed because, until the presentation, they were not aware of any problem.

On October 11, 2001, DOH met with a Tongan (Pacific Islander) community group during a monthly community meeting in Burien, Washington. A variety of maps and large pictures of fish species reportedly harvested from the LDW were used as visual aids. All participants spoke English so an interpreter was not required. There was concern about consumption of salmon from the LDW and questions regarding its safety. Participants want to know if seafood at the markets is safe to eat and what precautions are taken to ensure food safety. They do not eat fish organs and want to learn more about shellfish harvesting. This group agreed to spread word of the existing health advisory to family and friends. They did not have health concerns because they were not aware of a problem until the meeting.

On November 9, 2001, the PAEP arranged for DOH to meet with Samoan senior citizens at a meal-site at the Rainier Community Center. Seven people participated in the meeting. Most of the Samoan seniors were familiar with the Duwamish River. They stated that many people fish there, but they do not know these people personally. The elders were concerned about salmon. They agreed to spread word of the existing advisory to their communities. One woman had friends that live in the South Park neighborhood. They also requested that DOH return with the results of the public health assessment. The Samoan coordinator for this meal site told DOH that the people who live in the South Park neighborhood are Tongan, not Samoan. She knew other Samoan groups that fish and would be interested in a public health message regarding the Duwamish Waterway. She agreed to help DOH meet with them when the health assessment is completed.

On October 12, 2001, DOH met a with a Cambodian meal site group consisting of approximately 30 adults and several children at their Friday brunch located at the Park Lake Community room in White Center. A variety of maps and large pictures of fish and shellfish species were used as visual aids. Most participants did not speak English and the hosting community leader offered his services as an interpreter. No one would say if they fished in the LDW, but they all were aware of its location. This group consumes fish eggs but does not eat fish organs. The safety of market bought seafood was a common concern. The group questioned whether seafood would be safe to harvest after the LDW is cleaned up and how long the cleanup would take. There was interest in learning about safe-harvesting techniques. This group agreed to spread word of the existing health advisory to their friends and family members but did not have health concerns because they were not previously aware of contamination in the LDW. After the presentation and discussion, the interpreter mentioned that several people fish in the LDW to feed their families. The interpreter also indicated that a video in their own language may be a useful method to use for health education.

DOH met with a second Cambodian meal-site group on October 17, 2001, at a brunch located at the YMCA in the High Point neighborhood. Approximately 28 adults and a few children participated. Two of the adults were present at the Cambodian brunch in White Center the previous Friday. Most participants did not speak English and the hosting community leader served as an interpreter. Everyone knew where the LDW was located, but would not say if they fished there. The group wanted to know if seafood at markets is safe and, if so, how is the safety of market fish ensured. Concern about salmon caught in the LDW was also identified. Participants want to learn more about safe harvesting and agreed to spread word of the existing advisory to their families and friends. They also did not have health concerns because they did not know there was a contamination problem until that time.

Tribal Issues

DOH values tribal participation. The Suquamish, Muckleshoot, and Duwamish Tribes are deeply invested in the Duwamish River for harvesting, cultural, and spiritual purposes. Although the Duwamish Tribe is not currently recognized by the federal government, DOH acknowledges their extensive cultural involvement with the river. Tribal health concerns are discussed below.

Muckleshoot Tribe

On June 26, 2001, DOH met with a representative and biologist for the Muckleshoot Tribe to discuss fishing habits and health concerns related to the LDW site. The Muckleshoot Tribe is particularly concerned because the site comprises a significant area of their U & A fishing grounds as guaranteed by federal treaty law. The Tribe expects EPA to provide maximum protection of these grounds. The Muckleshoot Tribe is primarily concerned about the following:

  • Dermal contact with contaminated sediments as tribal members are checking fishing nets.
  • Occupational exposure to fisherman exercising their treaty rights.
  • Understanding the implications of risk associated with consumption of adult salmon.

Duwamish Tribe

DOH met with a tribal leader from the Duwamish Tribe on July 6, 2001, to gather health concerns and perspectives on fishing habits. The Duwamish Tribe believes in using traditional fishing methods, not modern fishing methods. The Duwamish Tribe is especially concerned about the following:

  • Frustration because the process of completing a public health assessment takes a significant amount of time.
  • Establishing consistent relationships with agencies involved in LDW cleanup activities (the Duwamish Tribe prefers to communicate with the same individuals over time).
  • Government agencies afraid to approach issues regarding the LDW because of the industrial corridor.
  • General human health effects of eating fish from the LDW.
  • Cancer and leukemia from eating fish from the LDW.
  • The health of new immigrants (specifically South East Asian) who fish on the river to feed their families.
  • Mishandled resources, particularly the fishery.
  • Methods of sediment core sampling.
  • Raw sewage discharged into the waterway.

Suquamish Tribe

On April 15, 2002, DOH met with the Suquamish Tribal biologist, Environmental Program Manager, and Fisheries Policy Liaison to discuss the tribe's health concerns related to the Duwamish River. The meeting was held at the Suquamish Tribe's offices. DOH staff had recently attended the Governor's Office of Indian Affairs "Government to Government Training" to learn more about tribal perspectives.

The tribe stated that they take the seven generation approach to natural resource management. The tribe considers Elliott Bay and the Duwamish River to be part of their U&A fishing area. The tribe currently fishes commercially for salmon up to the Spokane Street Bridge (the mouth of the Duwamish). Fishers may keep other species for family consumption while fishing for salmon. The tribe is very concerned about pollution and wants children's exposures to contaminated sediments while netfishing to be considered. The following are the Suquamish Tribe's primary health concerns:

  • Future of shellfish harvesting in the Duwamish River.
  • Sewer outfall and raw sewage problems.
  • Tumors in fish.
  • Cancer.
  • Safety of consuming resident fish and shellfish (species that do not migrate).
  • Exposures to children fishing with their parents.
  • The dramatic increase in diabetes and other health problems that result when native people decrease their seafood consumption and substitute less nutritious food items.

South Park Neighborhood Association

On April 9, 2002, the DOH Community Outreach Educator met with the South Park Neighborhood Association (formerly the South Park Crime Prevention Council). Approximately 25 people attended the meeting. All attendees were white except for one African-American teen. The emphasis of the meeting was on teen recognition and service in the community. The second half of the meeting was devoted entirely to crime prevention issues. DOH encouraged teen participation in community outreach messages regarding the Duwamish River and welcomed input from meeting participants. Maps with a toll-free contact number were distributed. When questioned about the Duwamish River, members stated they do not fish or swim in the river. Three people kayak in the river, four people have pets that swim in the river, and four raised their hands when asked if they have contact with sediments in the parks along the water. Members expressed concern regarding prompt notification should a health hazard be determined to exist at the Duwamish River site.

Cleanup Coalition River Tour

The Duwamish River Cleanup Coalition (DRCC) is comprised of the People for Puget Sound, Puget Soundkeeper Alliance, Waste Action Project, Environmental Coalition of South Seattle, Duwamish Tribe, Green-Duwamish Watershed Alliance, Washington Toxics Coalition, Georgetown Community Council, and the Community Coalition for Environmental Justice. The DRCC sponsored a boat tour of the LDW on September 8, 2001. DOH was invited to attend in order to interview individuals regarding potential health concerns, particularly those who may be directly involved in restoration work along the LDW and who may be exposed to contaminated sediments. Approximately 40 people participated in the boat tour. Seven people expressed interest in the public health assessment, but had no human health concerns to report.

South Park Marina

Two DOH representatives were available from 9 a.m. to noon at the South Park Marina on August 25, 2001. The purpose of this activity was to collect health concerns from marina users regarding the LDW site. Flyers were prominently posted on marina property by the manager one week prior to the availability session. A large aerial photo and map of the LDW site, informational handouts, and a table and chairs were set up outside the office of the South Park Marina. The marina manager was very knowledgeable about the site and supportive of DOH's presence. Flyers were also sent to the manager of the Duwamish Yacht Club for distribution prior to the event. A local activist and marina tenant advocated participation to marina tenants prior to August 25, and met with DOH at the marina on the day of the availability session.

Seven people spoke with DOH staff and asked questions and shared their health concerns. The community activist believes that people he spoke with previously are overwhelmed by the magnitude of the LDW site and prefer to remain anonymous and not receive more bad news about contamination present in the LDW. Distrust of government, fear, and weariness may be hindering communication with some marina tenants. Five of the respondents were middle-aged white men and the other two were a retired couple that live adjacent to the marina. No human health concerns regarding the LDW site were documented during the session. Most of the participants had some knowledge about the site and all were very interested in the cleanup process. One tenant expressed the desire for "a clear message" and "just tell me what I need to know." No feedback was received from marina users at the Duwamish Yacht Club.

Interview with Washington Department of Fish and Wildlife Enforcement

On October 3, 2001, DOH conducted a telephone interview with an enforcement officer for the WDFW responsible for patrolling the LDW study area. The enforcement officer indicated that he has observed approximately 20-30 people fishing in the area (mostly Asian, a couple of Hispanic, and a few Russian). Several men enjoy fishing in the middle of the night. Salmon fishing is popular during late summer and fall. The enforcement officer has observed people fishing from the following locations: Spokane Street bridge near the south end of Harbor Island (shiner perch, flounder, herring, Dungeness crab, red rock crab, graceful crab, sculpin, and squid), Terminal 105 bridge (shiner perch, flounder, and herring), Highway 99 bridge (barred perch and flounder), railroad bridge (Dungeness crab, red rock crab, graceful crab), and Kellogg Island (fresh water clams/mussels). These locations are identified in Figure 4.

Russian and Ukrainian Communities

DOH made several attempts to contact the Russian community through refugee/immigrant organizations, social workers, food banks, churches, and housing developments. An appointment to meet with a Ukrainian church group in White Center on October 14, 2001, was canceled by the pastor. An extreme distrust of government agencies exists within the Russian and Ukrainian communities. Community leaders are interested in health messages but are reluctant to meet with government agency staff.

On November 8, 2001, DOH and PH-SKC met with a Russian/Ukrainian translator who immigrated to the United States from the Chernobyl area in 1998. The translator explained that people from the former Soviet Union are very fearful of government and punishment by the government. She described it as "genetic fear." She stated that many immigrants find refuge in Pentecostal religion and are a very closed people. The prevailing attitude is "we have our culture and you have yours." The belief is that the less known about them, the less they can be manipulated and hurt. The translator agreed to help DOH and PH-SKC communicate with Russian and Ukrainian groups if the agencies establish a connection with a community leader.


A. Introduction

A considerable amount of chemical and biological contaminants have been released into the LDW over the past 90 years. Contaminants move to the river through surface water runoff, storm drain systems, combined sewer overflows, permitted industrial discharges, and non-point source runoff from commercial and industrial operations. The resulting contamination has contributed to the process of bioaccumulation in fish, shellfish, and crab. Bioaccumulation varies considerably with respect to the type of contaminant and the affected species. [15]

Contaminants of Concern: Contaminants of concern (COCs) are those chemicals found at the site that may cause health effects. Not all chemicals found at the site are COCs and not all COCs are health hazards. COCs found in sediment and fish/shellfish are evaluated in the Pathways Analysis/Public Health Implications section.B. Contaminants of Concern

Tables 3 and 4 below list contaminants of concern (COCs) for each completed exposure pathway. Each contaminant is compared with a health comparison value (i.e., screening value) to see if it is occurring at a high enough level to warrant further consideration. If a contaminant exceeds its health comparison value for a specific media (e.g., fish, shellfish or sediment), it is evaluated further under the Pathways Analysis/Public Health Implications section. The fact that a contaminant exceeds its health comparison value does not mean that a public health concern exists but rather signifies the need to consider the chemical further. The health comparison values used in this public health assessment include screening values in fish from EPA guidance, [16] environmental media evaluation guides (EMEGs), cancer risk evaluation guides (CREGs), reference dose media evaluation guides (RMEGs), EPA Region 9 Preliminary Remedial Goals (PRGs), and Model Toxics Control Act (MTCA) cleanup values for soil. Appendix F explains the screening process in detail.

Also included in the COC tables are EPA's weight-of-evidence cancer classifications for each contaminant. This classification scheme will be revised in the near future but currently consists of six groups: 1) Group A - Known Human Carcinogen, 2) Group B1 - Probable Human Carcinogen with sufficient animal data and limited human data, 3) Group B2 - Probable Human Carcinogen with sufficient animal data and inadequate or no human data, 4) Group C - Possible Human Carcinogen, 5) Group D - Not Classifiable as to Human Carcinogenicity and 6) Group E -Evidence of Noncarcinogenicity in Humans

  1. Fish/Shellfish

A number of fish species are harvested from the LDW study area by subsistence and recreational consumers. In order to evaluate the fish consumption pathway, target species were selected in order to evaluate contaminant concentrations in different fish groups. Chinook and coho salmon were evaluated as part of the anadromous group, English sole was selected to represent bottomfish, and perch were used as a surrogate for the pelagic group. Quillback rockfish were also evaluated because of high levels of PCBs and mercury detected in samples from Elliot Bay near Harbor Island, although it is not clear as to whether or not this species is present in the LDW. Red rock and dungeness crab were also evaluated based on information that these species are consumed from the LDW. Table 2 shows the type and quantity of fish samples that were used to characterize fish populations in the LDW.

Table 2.

Distribution of fish sample analyses by species used in the health assessment of the Lower Duwamish Waterway site, Seattle, Washington.a
Species Composite Individual Total Number of Fish or Shellfish Sample Location
Chinook 31 34 171 See Figure 2f
Coho 44 1 205 See Figure 2f
English Sole 18 3 164 See Figure 2a
Striped Perch 8 1 52 See Figure 2b
Rockfish 0 5 5 See Figure 2e
Mussels 0 63 63 See Figure 2d
Dungeness Crab 0 3 3 See Figure 2c
Red Rock Crab 9 0 45 See Figure 2c

a = Sample numbers are based on analysis for total PCBs

Contaminants that exceeded comparison values are presented in Table 3 as contaminants of concern(COC) that require further evaluation. Comparison values are screening values, and the listing of a contaminant in Table 3 does not mean an adverse health effect will result from exposure. Potential health effects from exposure to contaminants listed in Table 3 are evaluated in the Pathways Analysis/Public Health Implications section of this health assessment.

Table 3.

Contaminants of concern in fish from the Lower Duwamish Waterway a
Contaminant Maximum/Weighted Average Comparison Valueb Cancer Class
Chinook Salmon Coho Salmon English Sole Quillback Rockfish Red Rock Crab Dungeness Crab Perchc mussels
Arsenic (mg/kg) 1.4/
NA NA 12.5/
0.003 A
Cadmium (mg/kg) NA NA <0.05 NA NA <0.02 NA 0.7/
0.5 B1 (inhalation)
Chlordane (ug/kg) 15/
NA NA NA NA <7 14 B2
cPAHs (ug/kg) d <50 <47 <49 NA NA <29 NA 62/
0.7 B2
DDE (ug/kg) 33.8/
<0.1 NA NA NA <1.3 14 B2
PCBs (ug/kg) 160/
2 B2
Mercury (ug/kg) 150/
49 NA

a = Values are for chemicals present in skinless fillets or edible tissue unless otherwise noted
b = Comparison values for contaminants in fish were obtained from EPA Guidance for Assessing Chemical Contaminant Data (subsistence fishers)
c = Arsenic level in perch was calculated from 3 whole body shiner perch samples. Other contaminant levels were calculated from skinless striped perch fillets.
d = Carcinogenic Polycyclic Aromatic Hydrocarbons - Benzo(a)pyrene Toxic Equivalent (TEQ)
A - Human Carcinogen
B1 - Probable Human Carcinogen
B2- Probable Human Carcinogen; inadequate human evidence, sufficient animal evidence
NA - Not available

  1. Sediment

Approximately 1,200 surface sediment samples have been collected from the LDW study area within the past 10 years. Phase I of the LDW RI compiled all existing sediment data sets for the LDW and applied a defined set of data quality objectives to determine if the data would be included and used in the RI. [17]

Surface sediment data from 25 sampling events were included in the database for evaluation in the RI. Surface sediments are defined as sediments less than 15 centimeters (cm) deep, and subsurface sediments are defined as sediments greater than 15 cm deep. Approximately 400 surface sediment samples were collected from intertidal areas along the LDW, and the remainder were collected from subtidal locations. Intertidal areas are those that are submerged during high tide and exposed during low tide.

It should be noted that these data were provided to EPA and Ecology in October 2001 for quality assurance review, and were still being evaluated by both agencies at the time this public health assessment was prepared. The sediment data set for the LDW will be re-evaluated by DOH following final review by EPA and Ecology.

Contaminants of concern in LDW sediments are shown in Table 4. The screening process used to select COCs in sediment is described in Appendix F. Although concentrations of mercury, cadmium, DDE, and chlordane in sediment were below comparison values, they were included as contaminants of concern to be evaluated in conjunction with the fish consumption pathway.

Table 4.

Contaminants of concern in sediment at the Lower Duwamish Waterway site located in Seattle, Washington
Contaminant Average Concentration 95th Percentile Concentration Comparison Value Source
Arsenic (mg/kg) 14 30 20 EMEG
Cadmiumb (mg/kg) 1.2 2.8 10 EMEG
Chlordaneb (ug/kg) 10 37 2000 CREG
DDEb (ug/kg) 5 12 2000 CREG
Mercuryb (mg/kg) 0.29 0.64 5 RMEGa
cPAH'sc (ug/kg) 0.52 1.4 0.1 CREG
Polychlorinated Biphenyls (PCB's) (ug/kg) 2203 4406 400 CREG

a = RMEG is for methyl mercury
b =Contaminants were included in list of sediment COCs due to fish consumption pathway
c = Carcinogenic Polycyclic Aromatic Hydrocarbons - Benzo(a)pyrene Toxic Equivalent (TEQ)

C. Quality Assurance and Quality Control

This public health assessment relies upon information provided in the referenced documents and assumes that adequate quality assurance and quality control measures were followed regarding chain of custody, laboratory procedures, and data reporting. The validity of the analysis and conclusions drawn in this public health assessment are dependent upon the completeness, relevance, and reliability of the referenced information.

D. Physical Hazards

There are a number of physical hazards within the LDW study area including riprap, rubble, storm drains, sewer outfalls, as well as elevated shoreline access points without railings. The waterway is heavily used for cargo transport by commercial vessels which may pose a hazard to recreational users of the waterway. In addition, there are physical hazards such as debris, glass, and unstable rock and riprap materials which could represent a concern. Physical hazards are not quantified in this public health assessment.

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