Introduction:

The purpose of this project is to investigate if local community partners, with guidance from the regional scientist, could collect and prepare moss samples to be analyzed for heavy metals. The study came together by convening local partners who had a shared interest in community-led air monitoring projects.

The Duwamish River Cleanup Coalition's Clean Air Program, in collaboration with the U.S. Forest Service's Pacific Northwest Research Station and other partners demonstrate the value of community-gathered moss data as living indicators of air pollution in Seattle's Duwamish Valley. These data can help identify potential areas of high air pollution for follow up monitoring and mitigation.

Youth Corps were trained on how to collect moss samples to use as an indicator of air pollution by Forest Service scientists and DIRT Corps community members. In all, they collected 80 moss samples from street trees in a 5,300-acre grid covering South Park and Georgetown. Scientists then re-sampled moss at 20 locations sampled by the youth corps for comparison. All 100 samples were analyzed in the Forest Service's Grand Rapids Laboratory for a suite of 25 metals and other elements---including heavy metals like arsenic, lead, and chromium---all of which occur naturally in the environment but which tend to concentrate in cities and industrial areas from sources like traffic and industry.

Our main concern:

This project aims to use the information gathered from moss sampled to reduce air pollution and, ultimately, improve the community's health.

Air monitoring studies have shown the lower Duwamish Valley has some of the worst air quality in the region, but little is known about the local concentrations and specific causes of the pollution. A persistent barrier to cleaning up air pollution in major cities is that it is very difficult to identify localized pockets of pollution at the block or neighborhood scale. Sampling tree moss can help with this problem.

Obstacles and supporting information:

There are many potential causes of high metal concentrations in moss, and this community-led research team is currently working to identify patterns of metal concentrations and possible causes and to study the potential value of different pollution mitigation approaches.

Who is engaged in this concern?

• Trained local youth, Duwamish Valley Youth Corps
• Duwamish Valley Clean Air Program Stakeholders
• Academic, non-profit and governmental partners

The analysis can help the community, regulatory agencies, and the governments to collaborate on next steps to address air quality issues in the Duwamish Valley and, in this way, empower the community to address local air pollution. In the meantime, the Duwamish Valley Cleanup Coalition is sharing the study's initial findings with local, regional, and federal regulatory agencies to begin conversations about potential mitigation efforts.

What Are the Initial Questions?

• Can a successful heavy metal analysis using moss samples be designed for community partners?
• What is the best way to collect moss studies in an urban environment?
• What can moss tell us about metals indicators?
• Is more metal analysis needed? What baseline measurements are available?