Studies of Cigarette Smoke Transfer Using Radioisotopically Labelled Tobacco Constituents: Part III: The Use of Dotriacontane-16,17-¹⁴C as a Marker for the Deposition of Cigarette Smoke in the Respiratory System of ExperimentaI Animals

The determination of the mass-balance after smoking of dotriacontane-16,17-¹⁴C added to cigarettes is described. The radiolabelled compound was associated exclusively with the particulate phase of Abstract: The determination of the mass-balance after smoking of dotriacontane-16,17-¹⁴C added to cigarettes is described. The radiolabelled compound was associated exclusively with the particulate phase of smoke and transferred from the tobacco with a minimum of pyrolysis. Details are given of the construction and operation of the Animal Smoking Apparatus used for exposing rats to cigarette smoke. Dotriacontane-16,17-¹⁴C was used to give an indication of the amount of total particulate matter (TPM) inhaled and retained by rats exposed to mainstream smoke. The mean amounts of dotriacontane-16,17-¹⁴C deposited in the head, and in the larynx, trachea and lungs of each of 20 animals treated in the apparatus were found to be, with 95 % confidence Iimits, (2.2 ± 1.4) % and (7.0 ± 3.1) % respectively of the mean total dotriacontane-16,17-¹⁴C content of mainstream TPM.