Neglected plastic waste from discarded cigarette butts: A case study on hazards identification in typical regions in...

Discarded cigarette butts (DCBs), a prevalent yet underregulated environmental plastic pollutant, require urgent hazard assessment given China's status as the world's largest cigarette producer/consumer. Considering the diverse criteria and requirements for waste hazard characterization across nations, we performed a comprehensive hazard characterization, including the leaching toxicity, toxic substance content, and acute toxicity, of DCBs collected in typical regions of China as a focal case study. The results indicate that the cumulative toxic substance content equivalent was found to be 0.99, nearing the hazardous waste threshold of 1, with nicotine responsible for 75.2 % of this total. Although the findings do not definitively label DCBs as hazardous waste, they strongly imply their proximity to such a categorization based on the toxic substance content. Considering the substantial annual volume of DCBs, it is imperative to consider the rigorous environmental and health risk assessments and the implementation of comprehensive, science-driven management measures.