Filtering Smoke, Polluting Water: Cellulose Acetate Cigarette Filters as a Rapid Source of Tobacco-Derived Chemicals.

Cigarette butts, including their cellulose acetate (CA) cigarette filters (CFs), are a source of toxic chemical pollution to aquatic environments. We investigated the sources, kinetics, and environmental fate of chemicals leaching from CFs in water. Most compounds leached from unsmoked and machine-smoked CFs within 1 h, plateauing at 38.4 ± 4.8 and 41.5 ± 4.9 mg dissolved organic carbon (DOC) per gram CF, respectively. We found that CA polymer contributes negligibly to organic CF leachates. Smoked filters consistently released higher concentrations of DOC, total dissolved nitrogen (TDN), and aromatic and fluorescent compounds than unsmoked filters. We conclude that leachate fluorescence and TDN likely originate from tobacco residue, while DOC derives from both smoking and filter additives. Simulated sunlight had no effect on DOC release but the increase in TDN and reduction of nicotine-like fluorescence in smoked CF leachates reflect the transformation of aromatic alkaloids into new compounds. DOC leaching kinetics were estimated using a radial diffusion model, which confirmed that >98% of DOC was released within the first hour in ultrapure water (>85% in synthetic stormwater), and indicate surface area and internal diffusion limitations. These results inform future predictions of CF pollutant release and mitigation efforts to reduce its source.