A ubiquitous tire rubber–derived chemical induces acute mortality in coho salmon
Zhenyu Tian, Haoqi Nina Zhao, Katherine T. Peter, Melissa Gonzalez, Jill Wetzel, Christopher L. Wu, Ximin Hu, Jasmine Prat, Emma Mudrock, Rachel Hettinger, Allan E. Cortina, Rajshree Ghosh Biswas, Flávio Vinícius Crizóstomo Kock, Ronald Soong, Amy Jenne, Bowen Du, Fan Hou, Huan He, Rachel A. Lundeen, Alicia N. Gilbreath, Rebecca Sutton, Nathaniel L. Scholz, J. W. Davis, Michael C. Dodd, André J. Simpson, Jenifer K. McIntyre, Edward P. Kolodziej
Abstract
Tire tread particles turn streams toxic For coho salmon in the U.S. Pacific Northwest, returning to spawn in urban and suburban streams can be deadly. Regular acute mortality events are tied, in particular, to stormwater runoff, but the identity of the causative toxicant(s) has not been known. Starting from leachate from new and aged tire tread wear particles, Tian et al. followed toxic fractions through chromatography steps, eventually isolating a single molecule that could induce acute toxicity at threshold concentrations of ∼1 microgram per liter. The compound, called 6PPD-quinone, is an oxidation product of an additive intended to prevent damage to tire rubber from ozone. Measurements from road runoff and immediate receiving waters show concentrations of 6PPD-quinone high enough to account for the acute toxicity events. Science , this issue p. 185