Short-Term Effects of Cigarette Smoking on Bronchial Clearance in Humans

Interspecies comparisons of particle deposition and mucociliary clearance in tracheobronchial airways

“…Cigarette smoke affects mucociliary transport in humans (Albert et al, 1971a(Albert et al, , 1973(Albert et al, , 1975Camner and Philipson, 1972 Camner et al, 1973;Sanchis et al, 1971;), but the reported effects have included both accelerated and slowed clearance. Some confusion has arisen because of the differences in dose and dose rate in studies focussed on the short-term effects of recent smoke exposures.…”

“…These included: (1) intermittent retrograde mucus flow in the trachea, (2) intermittent clearance, in which periods of clearance stasis alternate with abrupt drops in retention, and (3) long delays in the onset of clearance followed by rapid clearance (Albert et al, 1971a(Albert et al, ,b, 1973. After the end of the exposure series, mucociliary clearance from the deep lung was faster than in preexposure control tests in two animals, but slower in the third.…”

“…In humans, exposure to the smoke from 2 to 7 cigarettes resulted in a twofold reduction in the time required to complete 90% of the bronchial clearance (7~9 0 %) in both 9 nonsmokers and 6 smokers (Albert et al, 1975). In 3 donkeys, exposure to the whole fresh smoke from 2 cigarettes had a similar effect, while short-term exposures to the whole smoke from 10 cigarettes produced a transient slowing of upper bronchial mucus transport lasting less than 15 min, and whole smoke from more than 15 cigarettes extended the duration of bronchial clearance by a factor of 2 or more (Albert et al, 1974).…”

Effects of sulfate aerosols in combination with ozone on elimination of tracer particles inhaled by rats

“…Cigarette smoke, a toxic mixture and frequent coinsult in human inhalation exposure situations, has been relatively well studied. Albert et al (1969Albert et al ( , 1970Albert et al ( , 1974 found effects in humans and donkeys that depend on dose level and duration of exposure. Low single doses or a few repeated exposures to smoke were associated with accleration of clearance rates in the tracheobronchial tree in both species.…”

Effects of inhaled acids on respiratory tract defense mechanisms.

“…Figures 1A and 2 show the concentration-response profiles for H2S04 determined in humans (16) and rabbits (21), respectively, in this laboratory. The ability of an inhaled irritant to stimulate mucociliary clearance at low exposure concentrations while slowing it at higher levels was previously demonstrated in this laboratory on both animals and human volunteers using another irritant, whole fresh cigarette smoke (22)(23)(24). The actual H2SO4 exposure level needed to produce an observed acceleration may be dependent upon the region within the bronchial tree from which clearance is being measured, in relation to the region which is most affected by the inhaled acid mist.…”