Environmental fate of rubber additives originating from electric vehicles

We will study the unintended contamination from the greener switch to electric vehicles. Electric vehicles wear through tires faster than combustion vehicles due to their increased weight and instant torque. Due to wear-and-tear, tires release small particles and additives from the rubber, which can have harmful effects to the environment. Our research studies these additives such as rubber vulcanizers and antioxidants, including the notorious 6PPD-q, which causes mass death of Coho salmon in the Pacific Northwest. What is currently missing from the assessment is understanding the persistence of contaminants in freshwater ecosystems. That is, once washed into the creeks and rivers, how long do they persist in the water column, and what do they break down to? In the case of the additive 6PPD, one transformation product is 6PPD-q, which is causes the majority of toxicity and emphasized the need to characterize transformation products. In order to determine if the increased emission from electric vehicles is meaningful, environmental fate data of these additives is required. Specifically, we are identifying chemical components from tire rubber using high resolution mass spectrometry, and studying degradation in natural waters via aquatic photochemistry reactions.