CORESTA Meeting, Smoke Science/Product Technology, 2017, Kitzbühel, STPOST 22

Dosimetry: TPM and nicotine delivery of combusted tobacco products to the 24 and 96 Multi Well Plate and inserts on Smoke Aerosol Exposure In Vitro System (SAEIVS)

(1) Reemtsma Cigarettenfabriken GmbH (an Imperial Brands PLC Company), Hamburg, Germany; (2) Imperial Tobacco Limited, Bristol, U.K.

In vitro exposure systems are key tools for the risk assessment of emerging electronic nicotine delivery systems as well as for conventional tobacco products. The Smoke Aerosol Exposure in vitro System (SAEIVS) used at Imperial Tobacco Limited is designed to expose cells in multiwell plates (MWP) under Air Liquid Interface (ALI) conditions[1]. This procedure allows direct contact of both aerosol particles and gas phase components with the apical humid cell surface, mimicking the lung surface in vivo.

The exposure to the undiluted or diluted smoke can be performed in cells cultivated either on a collagen I matrix in 96 MWP or on inserts / transwells in 24 MWP format. Up to five tobacco products can be puffed simultaneously. This study presents the initial efforts to determine total particulate matter (TPM) and nicotine delivery from cigarettes to the wells of MWPs and inserts by physico-chemical analysis. The analytical determinations (LC/MS-MS) of nicotine were compared to optical density measurements of TPM at 400 nm. This method[2] allows an evaluation of water free deposited condensate for calculation of more reliable dose response effects caused by toxicologically relevant substances.

At first the influence of the exposed surface texture on deposition efficiency without cells was tested. As expected significant differences were found between dry and moistened plastic surfaces. In the next step, cell coated surfaces were exposed to smoke in order to mimic more realistically the deposition under ALI conditions. The amounts of TPM and nicotine deposited on the coated surface were compared to that found with the exposed living cells. Optical density measurement of tobacco smoke condensate provided reliable results which were comparable to those obtained by the standard LC/MS-MS and GC chemical analysis. Tobacco blend specific calibration curves will enable the estimation of the particle and nicotine concentration delivered to the wells in future experiments.

[1] Wieczorek R.; Trelles Sticken E. CORESTA Meeting, Smoke Science/Product Technology, 2015, Jeju, ST 44
[2] Wieczorek R.; Röper W.; Burghart H. CORESTA Meeting, Smoke Science/Product Technology, 2005, Stratford-upon-Avon, SSPT 24