Presenters – Ximin Hu, University of Washington

In the U.S. Pacific Northwest, one species of salmon, (coho salmon, Oncorhynchus kisutch), annually exhibit previously unexplained acute mortality upon stormwater exposure when adult salmon migrate to near urban creeks to spawn. We subsequently identified the transformation product “6PPD-quinone” of the globally ubiquitous tire rubber antioxidant 6PPD as the primary causal toxicant for coho salmon mortality. Subsequent research efforts have shown that this compound is ubiquitous in roadway environments and highly toxic to several species of fish. Here, we describe some of our recent research efforts to describe the chemical properties of 6PPD-quinone and its environmental occurrence and fate. Additional results related to treatment of roadway runoff in several representative treatment systems also will be presented.