About the event
Roadway Runoff As A Source of Toxic Trace Organic Contaminants To Surface Waters
Abstract: In the U.S. Pacific Northwest, one species of salmon, (coho salmon, Oncorhynchus kisutch), annually exhibit unexplained acute mortality upon stormwater exposure when adult salmon
migrate to urban and near urban creeks to reproduce. By investigating this phenomenon with a portfolio of techniques based upon liquid chromatography-high resolution mass spectrometry,
we identified a quinone transformation product of a globally ubiquitous tire rubber antioxidant as the primary causal toxicant for this mortality phenomena. Retrospective analysis of representative roadway runoff and stormwater-impacted creeks of the U.S. West Coast indicated widespread occurrence of the quinone product (<0.3-19 μg/L) at toxic concentrations (LC50 of 0.8±0.16 μg/L). These results reveal unanticipated risks of tire rubber antioxidants to an aquatic species and imply toxicological relevance for widely dissipated tire rubber residues. Additional evaluation of the effects of roadway runoff on water quality and sensitive aquatic species is likely merited.