Multigenerational endpoints reveal detrimental effects of tire leachate in the marine mysid Neomysis awatschensis.

Tires generate tire wear particles (TWPs) through abrasion and release complex organic and inorganic compounds via leachates. In this study, we conducted a multigenerational assessment of the marine mysid Neomysis awatschensis exposed to sublethal concentrations (0.01, 0.05, 0.1 g L-1) of tire leachate across three generations to evaluate its long-term impact on chronic endpoints. The analyzed leachate contained high concentrations of zinc and several polycyclic aromatic hydrocarbons. Four-week survival rates revealed a dose-dependent increase in mortality in all generations (F0, F1, F2). Exposure to sublethal leachate concentrations significantly reduced feeding behavior, digestive enzyme activities, and acetylcholinesterase activity from the F0 generation onward, indicating enhanced transgenerational toxicity of the tire leachate. Furthermore, oxidative stress parameters (e.g., ROS and MDA) and antioxidant enzyme activities, including GST, GPx, GR, CAT, and SOD, increased across generations, accompanied by growth retardation, delayed molting, and reduced reproductive output. These findings highlight the potential risks of tire leachate exposure to mysid populations over multiple generations.