Cigarette Filters─A Neglected Source of Phthalate Exposure to Humans

Smoking is a significant contributor to premature death globally. While studies often focus on pollutants like nicotine and PAHs generated during smoking, little attention has been given to characteristic pollutants in cigarette filters, such as phthalates. In the present study, 20 phthalates were analyzed in 45 cigarette filters from seven countries. Phthalates were detectable in all samples, with the total concentrations in the range of 391.23–132216.69 ng/g (median: 1876.61 ng/g). Predominant phthalates included bis(2-butoxyethyl) phthalate (DBEP), di-n-butyl phthalate (DBP), and bis(2-ethoxyethyl) phthalate (DEEP), which collectively accounted for over 45% of the total concentrations. Daily exposure doses of phthalates from cigarette filters ranged from 30.99 to 10472.61 ng/(kg-bw day), with men's median intake approximately 1.25 times higher than women's. The total daily exposure doses varied by country in the order of Russia (median: 5092.72 ng/(kg-bw day)) > Japan (316.25) > China (240.36) > South Korea (199.37) > Switzerland (88.24) > USA (66.35) > Cuba (41.41). Carcinogenic risks associated with phthalate exposure exceeded 1 × 10–6, indicating significant health risks from this source of human exposure. This study for the first time represents a comprehensive evaluation of phthalate exposure from cigarette filters, confirming substantial risks associated with this overlooked source of human exposure.