UW SUPERFUND
Research Program Re-Funded
The US Environmental Protection Agency (EPA) is responsible for protecting the environment and public health from hazardous pollutants. Yet, contaminants still show up in our rivers, in fish, and even in us. For example, the lower Duwamish River, which is used by several species of Pacific salmon, is on the EPA Superfund National Priority List for remediation activities. Due to the river’s pollution levels, the Washington State Department of Health advises against eating crab, shellfish, and most kinds of fish from these waters.
The Comprehensive Environmental Response, Compensation, and Liability Act, commonly referred to as “Superfund,” was passed in 1980 to enforce the cleanup of hazardous waste sites. The EPA administers the program, in cooperation with state and tribal governments. Alaska, Washington, Idaho, and Oregon have 250 designated Superfund sites. Some of the waste site chemicals are not new, but persist in the environment for a long time.
How to effectively monitor these chemicals found at Super-fund sites and to determine the risk these substances pose to human, animal, and environmental health is critical to targeting public health interventions. The National Institute of Environmental Health Sciences (NIEHS) provides funding for university-based research through the Superfund Research Program (SRP), whose twofold mission is to conduct research into human and environmental hazards associated with Superfund chemicals and to develop methods for remediating toxic exposures.
In 2009, NIEHS renewed funding for the SRP housed in our department and directed by Professor Harvey Checkoway.
This federal funding has supported our program’s critical research on environmental pollutants for 23 years.
One of 15 nationally, the SRP at the University of Washington (UW) began in 1986 as a basic laboratory program to identify biomarkers that may reflect chemical exposures, biological damage, or an increased susceptibility to disease or injury in humans. Later, SRP’s emphasis shifted to applying basic research in real-life settings, namely, the effects of neurotoxicants, or chemicals that affect the nervous system, on human health and the environment. In humans, the amount of exposure to these chemicals can trigger a range of effects, from commonly occurring and reversible symptoms, such as dizziness or headaches, to irreversible nervous system damage that can result in debilitating neurodevelopmental disorders or chronic neurodegenerative diseases, such as parkinsonism.
Mixtures of environmental chemicals are present in local Superfund sites, such as the lower Duwamish waterway. Several species of Puget Sound salmon encounter low levels of pesticides and toxic trace metals during their migrations from fresh to salt water. Although some compounds are at levels not considered harmful, they can still interfere with the salmon’s ability to detect predators and prey and to locate their natal streams. Professor Evan Gallagher, deputy director of the UW SRP, is studying how certain Superfund pollutants interfere with salmon olfaction, which is the method salmon use to detect chemical cues in the water.
Using a combination of molecular biology and biochemical and physiological methods, his research team is developing biomarkers that can identify salmon populations undergoing olfactory injury in polluted environments. These biomarkers will also be able to delineate areas where salmon may be at risk of olfactory injury during their migrations.
The work being done by Gallagher and other SRP researchers will be used to develop genetic, ecological, and engineering methods to monitor environmental exposures, identify species and individuals at risk, and ultimately to reduce the risk of adverse biological outcomes associated with chemical exposures.
SRP researchers share relevant research findings and work with community and tribal groups who are concerned about hazardous waste. These include groups affiliated with the lower Duwamish waterway, Bunker Hill in Idaho, and the Midnite Mine on the Spokane Indian Reservation. SRP also works with various regional non-profits, which are involved in cleaning up hazardous waste sites in and near their impacted communities.
In another project, scientists are investigating the role of two genes (PON1 and PON2) in various neurodegenerative diseases, including Parkinson’s disease and cholinesterase inhibition from pesticide exposure in farm workers. Depression of the enzyme cholinesterase by certain pesticides can affect the normal transmission of nerve signals and result in continuous stimulation of the nervous system, manifested as muscle twitching, hypersecretion, nausea, and headaches. PON1 and PON2 are also enzymes, and play an important role in breaking down certain pesticides into less toxic forms.
Checkoway and Associate Professor Jing Zhang (UW Department of Pathology) lead other SRP projects. They are conducting research on a cohort of professional welders. Checkoway is involved with an epidemiological study to assess the effects of chronic exposure to manganese and other metals with risk, severity, and progression of clinically determined parkinsonism. Zhang is developing blood plasma biomarkers of parkinsonism among the welders, which may ultimately be used for early disease detection and prevention. Research Professor Stuart Strand (UW School of Forest Resources) is directing a project that develops poplar trees that are able to remove solvents and neurotoxic pesticides from the soil.
Ongoing research and outreach will ultimately contribute to an improved understanding of risks posed by hazardous waste chemicals.
For further reading
National Institute of Environmental Health Sciences
Photo by Dcoetzee, www.wikipedia.org
