Many generations of native people, and later immigrant communities from around the world, have relied on the Duwamish River as a source of sustenance. By the 20th century, Seattle came to rely on the river valley as a source of family-wage jobs.

Pollution from that industrial legacy led the lower Duwamish River to be designated as a Superfund site in 2001 by the federal Environmental Protection Agency (EPA). For what is probably the first time in Superfund history, a Health Impact Assessment (HIA) was part of the proposed plan for cleanup.

An HIA is a set of methods used to evaluate objectively the potential health effects of a policy, program, or project before it is imple­mented. HIAs have been used in Europe and elsewhere for many years, but are just begin­ning to gain acceptance in the United States.

The Duwamish cleanup is the type of population health problem that lends itself to such analysis, said Associate Professor William Daniell, of the Department of Environmental and Occupational Health Sciences (DEOHS) in the School of Public Health. The HIA focused on four vulnerable populations— local residents, affected Tribes, people who fish for food, and the Duwamish Valley workforce. Researchers from DEOHS, Just Health Action, and the Duwamish River Cleanup Coalition/Technical Advisory Group exam­ined a range of impacts, including the poten­tial health effects of community and industry gentrification, food insecurity, and disruption of cultural traditions.

"EPA studies focused on disease outcomes but didn't identify and evaluate broader implications for health and well-being," Daniell says. The HIA's recommendations would help protect the health of three Tribes impacted by the cleanup: the Duwamish, Muckleshoot, and Suquamish. In particular, the researchers suggest that the EPA collabo­rate with the Tribes to address their health concerns and restore safe access to natural resources and fish.

The chemicals of greatest concern are polychlorinated biphenyls (PCBs), carcino­genic polycyclic aromatic hydrocarbons, arsenic, dioxins and furans. Exposure comes from eating resident fish or shellfish and contact with contaminated sediment. These chemical compounds have been shown to cause cancer and a number of serious non-cancer health effects. Pregnant women and children are especially at risk.

The EPA's cleanup plan would reduce health risks, but it is not designed to lower contamination to current Puget Sound back­ground levels nor make resident seafood safe to eat on a regular basis. Instead, it recom­mends lower fish consumption. Subsistence fishers and Tribal members consume far more fish than average Americans.

If fishing were substantially restricted, subsistence fishers might experience food and nutritional insecurity. Many social and cultural traditions are tied to fishing. Graduate student Amber Lenhart convened focus groups of local fishers to assess how this loss of social ties would affect their Tribes' health and well-being.

The report emphasizes that subsistence fishers are predominately lower-income, people of color, immigrants, and non-English speakers. Their children could be particularly affected. The report calls into question whether the EPA is adequately complying with its own planning requirements for social and behavioral controls, such as fish advi­sories, which are used when the engineered cleanup falls short of health goals.

The HIA was submitted to the EPA during the public comment period in the summer of 2013 and is being reviewed along with the other public comments submitted. The final cleanup plan decision is expected later in 2014. Meanwhile, Daniell is working with his local partners to build coalitions that could remain involved throughout the EPA's Duwamish remediation. The City of Seattle has allocated a Duwamish Opportunities Fund, which is partially triggered by points raised by the HIA, Daniell says. Also, he and graduate student Jonathan Childers are evaluating how the HIA process worked for Tribes, communities, and decision-makers.

This project and report were supported by a grant from the Health Impact Project, a collaboration of the Robert Wood Johnson Foundation and The Pew Charitable Trusts, and also by the Rohm & Haas Professorship in Public Health Sciences, sponsored by the Rohm & Haas Company of Philadelphia.