title: Real-time measurement of particulate matter deposition in the lung.
abstract: Air pollution and cigarette smoke are recognized health risks. A method was developed for the measurement of the deposition fraction (DF) of polydisperse particulate matter (PM) in human airways. Ten normal volunteers [three females, age range 18-67 years, mean age (SD) 43.9 (14)] made single breath exhalations after inhalation to total lung capacity. The exhaled breath was diverted to a multichannel laser diffraction chamber where the particulate profiler measured 0.3 - 1.0-microm particles. DF was inversely related to expiration flow-rate, 0.69 (0.02) at 4 l min-1 and 0.5 (0.01) at 13 l min-1, respectively (p<0.05), and was influenced by the inhalation flow-rate [0.70 (0.02) at 3 l min-1 and 0.59 (0.02) at 13 l min-1, respectively (p<0.05)], while no differences were found between nasal and oral inhalation (0.68 (0.05) versus 0.67 (0.06), p>0.05). Higher breath holding times were associated with elevated DF [0.74 (0.02) at 20 s, and 0.62 (0.05) without breath holding (p<0.01)]. When the expiratory flow was controlled and the breath hold time standardized, DF was reproducible (CV = 4.85%). PM can be measured in the exhaled breath and its DF can be quantified using a portable device. These methods may be useful in studies investigating the health effects of air pollution and tobacco smoke.
authors.affiliation: Tobacco Control Unit, National Cancer Institute and SIMG-Italian College GPs, Milan, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Invernizzi
authors.forename: R
authors.initials: R
authors.lastname: Boffi
authors.forename: A A
authors.initials: AA
authors.lastname: Ruprecht
authors.forename: P J
authors.initials: PJ
authors.lastname: Barnes
authors.forename: S A
authors.initials: SA
authors.lastname: Kharitonov
authors.forename: P
authors.initials: P
authors.lastname: Paredi
mesh_terms: D000293:Adolescent; D000327:Adsorption; D000328:Adult; D000368:Aged; D000393:Air Pollutants / Q000493:pharmacokinetics; D045853:Exhalation; D005260:Female; D006801:Humans; D001239:Inhalation; D008168:Lung / Q000378:metabolism*; D008722:Methods; D008875:Middle Aged; D012107:Research Design; D012907:Smoking / Q000009:adverse effects*; D014028:Tobacco Smoke Pollution / Q000032:analysis*
chemical_list: D000393:Air Pollutants; D014028:Tobacco Smoke Pollution