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13. Determination of 4-(Methylnitrosamino)-1-(3-Pyridyl)-1-Butanone (NNK) arising from tobacco smoke in airborne particulate matter

Author

Aquilina, Noel J, Havel, Christopher M, Harrison, Roy M, Ho, Kin-Fai, Benowitz, Neal L, and Jacob Iii, Peyton

Subjects
Earth Sciences, Atmospheric Sciences, Climate-Related Exposures and Conditions, Lung, Cancer, Lung Cancer, Tobacco Smoke and Health, Prevention, Tobacco, 2.2 Factors relating to the physical environment, Carcinogens, Nitrosamines, Particulate Matter, Smoke, Nicotiana, Tobacco Smoke Pollution, Tobacco Smoke, Tobacco-Specific Nitrosamines, NNK, Environmental Sciences
Abstract

The most important tobacco-specific nitrosamine found in cigarette smoke and formed in ageing smoke after cigarettes are extinguished is 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK). It is formed from nitrosation of nicotine, under particular conditions both in indoor and outdoor environments. NNK has been classified as a potent lung carcinogen which is expected to be found primarily in the particle-phase and to be stable in particulate matter. In this study tests have been carried out to show that a bisulfate-treated filter is more efficient than an untreated filter to collect both nicotine and NNK, and that the latter is stable in outdoor particulate matter. To characterize NNK in the outdoor environment, airborne samples were collected from 11 cities in USA, UK, Hong Kong and Malta with characteristics varying from low to high population densities and from urban to suburban to rural, and with desert characteristics and distinct climates. It has been shown that airborne particle + gas phase nicotine and particle-phase NNK behave in a linearly correlated manner. A seasonal analysis was carried out on a subset of data available from five sites in California, where the load of NNK in PM10 is driven by long range transport of the air masses passing over densely populated cities. In the winter season, the load of NNK in PM is higher than in summer in a statistically significant manner. The contamination of PM with NNK shows variability, but is observed at all sites. This paper highlights the potential risk of chronic exposure to NNK in particulate matter by the inhalation pathway.

Published
2022

19. Ubiquitous atmospheric contamination by tobacco smoke: Nicotine and a new marker for tobacco smoke-derived particulate matter, nicotelline

Author

Aquilina, Noel J, Havel, Christopher M, Cheung, Polly, Harrison, Roy M, Ho, Kin-Fai, Benowitz, Neal L, and Jacob, Peyton

Subjects
Environmental Sciences, Pollution and Contamination, Tobacco, Social Determinants of Health, Tobacco Smoke and Health, Health Effects of Indoor Air Pollution, Cancer, Good Health and Well Being, Air Pollution, Indoor, Dust, Hong Kong, Nicotine, Particulate Matter, Tobacco Smoke Pollution, Nicotelline, Alkaloid, Second hand smoke, Particulate matter, Atmospheric marker
Abstract

Second Hand Smoke (SHS) has always been primarily linked with indoor pollution. To date nicotine was the favoured marker for SHS alongside measurements of particulate matter (PM) levels. As nicotine is mainly found in the gas-phase and reactive in the outdoor environment it is not ideal as a marker for the SHS-driven particulate component in PM. Nicotelline, a minor tobacco alkaloid that is stable, found almost exclusively in the particle phase and easy to quantify even at low concentrations, is being proposed as a better marker. It is the first study using bisulfate-treated quartz fiber filters to show that airborne nicotine (gas+particle phase) is directly proportional to airborne nicotelline in countries that have different climates. The analytical method developed has been validated to show that the use of untreated filters is suitable for the quantification of nicotelline even at low concentrations. Although nicotelline exhibits a seasonal and geographical variation, this is the first comprehensive study which demonstrates the ubiquitous presence of nicotelline in PM from outdoor air samples collected in the USA (0.1-285.6 pgm-3), UK (2.3-9.1 pgm-3), Hong Kong (3.8-109.3 pgm-3) and Malta (4.2-280.8 pgm-3). From the nicotelline apportionment factor of 1589 ng/mg of tobacco smoke PM we estimate the fraction of outdoor airborne PM derived from SHS to be in the range of 0.03-0.08%. While it is unlikely for tobacco smoke-related toxics in outdoor PM to be considered a major health hazard, in heavily polluted microenvironments this marker would be useful in tracing the presence of SHS and emerging Third Hand Smoke components that form or are found in airborne and settled PM that could induce serious health effects.

Published
2021

37. Corrigendum to ‘Personal exposure monitoring of fine and coarse particulate matter using exposure assessment models for elderly residents in Hong Kong’ [Chemosphere 357 (June 2024) 141975]

Author

Lui, Ka Hei, primary, Zhang, Tianhang, additional, Man, Chung Ling, additional, Chan, Chi Shing, additional, Ho, Steven Sai Hang, additional, Qu, Linli, additional, Kwok, Helen Hoi Ling, additional, Kwok, Timothy Chi Yui, additional, and Ho, Kin Fai, additional

Published
2024
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