Smoked cigarette filters are one of the most abundant littler found in coastal and urban areas. An estimated 6.25 trillion cigarettes are smoked per year worldwide. One study found that 76% of cigarettes smoked in urban areas were littered. It is, therefore, possible for cigarette butts to be transported by urban runoff to nearby water bodies. Despite the intensive studies of tobacco and tobacco smoke, studies on the fate and effects of smoked cigarettes are limited. In this study a non-targeted analysis based comprehensive two-dimensional gas chromatography analysis with time-of-flight mass spectrometry component identification (GC×GC/TOF-MS) was implemented to identify leachable chemical constituents and bioaccumulative compounds from smoked cigarettes in seawater leachate. A total of 844 unique compounds were found in the seawater leachate. Eighty-one compounds were tentatively identified by mass spectral similarity. Forty-seven compounds were confirmed with authentic standards while 12 compounds were not matched with authentic standards. Abundance order was made based on each compounds’ GC peak area. The top 20 most abundant compounds composed 71.75% of the total peak area. Based on the abundance and sources, nicotine, cotinine, anatabine and coexisting of diacetin and triacetin can be used as indicators of smoked cigarette contamination in coastal water. To determine the bioaccumulation of the leachable chemical constituents of smoked cigarettes, Mytilus galloprovincialis was exposed to the leachate at 1 smoked cigarette/liter for 28 days with a scientific control. In total, 329 unique compounds were found in the mussel exposed to the leachate. Fifty-one compounds were tentatively identified based on mass spectral similarity. Twenty-two compounds were found in both the leachate and the mussel exposed to the leachate suggesting that they were bioaccumulative. Among them, 11 compounds were confirmed with authentic standards: 2 furanmethanol; cotinine; benzyl alcohol; 4,4'- bipyridine; 2,3'-dipyridyl; pyrazine, ethyl-;1-pyrrolidinecarboxaldehyde; 2-cyclopenten-1- one, 2-hydroxy-3-methyl-; and pyrrolidine, 1-acetyl-. Some of the chemical constituents present in the mussel may exert have toxicity to human or animal. Further study is necessary for human exposure and risk assessment for persons that may consume such mussels. In environmental monitoring of mussel, we propose 2-furanmethanol, cotinine, 4,4’bipyridine and 2,3’-dipyridyl as potential suitable markers for evaluating cigarette litter pollution.