肺からの吸入たばこ煙のウォッシュアウト特性

抄録

Environmental tobacco smoke consists of 85 % of sidestream cigarette smoke and 11 % of exhaled mainstream smoke. In order to prevent non-smokers from passive smoking, exposure to the exhaled mainstream smoke as well as to the sidestream smoke has to be taken into account. In the present work, in order to elucidate the washout characteristics of inhaled smoke from the lung, smoking patterns were measured for the subjects with various vital capacities by using newly devised anemometer, and the particle concentrations and size distributions in the exhaled air were measured with SMPS (Scanning Mobility Particle Sizer, TSI Model 3936) and ELPI (Electrical Low Pressure Impactor, DEKATI Model 24317). As a result, (1) vital capacities of smokers do not affect the inspiration pattern of cigarette smoke, (2) exhaled air from a subject who is breathing room air contains particles with a bimodal distribution, (3) residual particles in the lung are washed out after 20 times of deep breathing, (4) human lung constantly generates particles with a median size smaller than 0.01 μm at the concentration of about 1.6 × 10⁴ cm^-3, (5) smoke exhaled from the lung has a bimodal distribution with the concentration of about 2.5 × 10⁷ cm^-3, (6) after smoking, complete washout of residual smoke in the lung requires normal breathing for 20 min.