Microplastics contamination in branded cigarettes: Characterization and potential burning inhalation risk assessment

<title>Abstract</title> It is well known that smoking is harmful to human health owing to the containing harmful substances. However, the study of prevalence and further harm to human of emerging pollutant microplastics (MPs) in cigarettes is still lacking. This study systematically analyzed 21 most kinds of most known and consumed domestic and international cigarette brands to ascertain the presence or absence of MPs in cigarettes. Experimental results illustrated that MPs were identified in 18 out of the 21 sampled cigarette brands with an average abundance of 0.21±0.61 items/g (0.15±0.44 items/individual). Among the identified MPs, the shape was mainly fibrous, predominantly colors blue and black, and particle sizes were mostly concentrated in 100-300 µm. A total of 6 polymer types were identified: rayon, polyester, polyethylene terephthalate, polyethylene, polydimethylsiloxane, and polyvinyl alcohol. After being burned, MPs would possibly produce toxic gases such as dienes, alkenes and alkanes, which can directly enter the human lung, resulting in further harm to human health. Besides, the daily and life time MPs exposure risk through cigarettes consumption was evaluated. These findings not only achieve a full and proper assessment of MPs contamination in cigarettes and potential risk to human, but also provides suggestions to minimize MPs contamination in cigarettes during the preparation process, aiming to reduce the risk of cigarettes being tainted by microplastics.