When the Rubber Hits the Road in Europe — A European Risk Perspective of 6Ppd-Quinone

6PPD-quinone (6PPD-Q), a transformation product of the tire antioxidant 6PPD, is among the most acutely toxic chemicals to certain salmonids. Since its 2020 identification, it has been implicated in coho die-offs in the U.S. Pacific Northwest and prompted regulatory responses in North America. In Europe, however, awareness, monitoring, and risk assessment remain limited despite dense road networks, urban runoff, and sensitive fish communities. This Perspective synthesizes current knowledge and key gaps in occurrence, exposure, and species-specific toxicity, and outlines a tiered response: harmonized water screening, targeted tests in native taxa, interim stormwater mitigation, and innovation toward safer tire additives.