Smoking and Tobacco Control Monograph No. 7 
Gori (1990a) noted that machines, unlike humans, smoke each cigarette 
in exactly the same way. Smokers usually inhale after taking a puff, and 
inhalation seems to be largely under the influence of nicotine demand. 
When smoking machines were invented, little was known about inhalation 
patterns. Today, inhalation can be measured with various biological markers, 
such as CO and cotinine (an indicator of nicotine intake). 
In a study of eight smokers. Gust and colleagues (1983) observed that the 
number of puffs and the duration, volume, and time between puffs varied 
with each smoker. All these factors affect the amount of smoke constituents 
to which the smoker is exposed. Gust and colleagues also noted that smoking 
patterns can vary as a smoker smokes a single cigarette. 
Observations of smoking behavior reveal that smoking patterns are 
influenced by a wide range of factors, including degree of nicotine 
dependence, environmental cues, stress levels, and personality variables. 
A survey of 1,200 randomly selected smokers and ex-smokers in the 
United States and Europe showed that consumers believe that the tar yields 
stated on cigarette packages accurately represent what is received by the 
smoker (Gori, 1990b). The majority of respondents indicated a belief 
that the published yield is equal to the amount consumed per cigarette. 
However, tar intake is related to nicotine intake, and individual intake 
of tar varies according to the nicotine levels of cigarettes and the level of 
nicotine dependence of smokers. 
Guyatt and coworkers (1989a, p. 192) studied the changes in puffing 
behavior during the smoking of a cigarette. The researchers reported 
The most important change in puffing behavior during a single 
cigarette is the reduction in puff volume since this directly 
affects smoke uptake. Most subjects showed this effect, but the 
proportional change was independent of the tar level of the 
cigarette smoked or the sex of the subject and was consistent 
between sessions. However, there were significant between- 
subject differences indicating that each individual had [an] 
idiosyncratic pattern. Most subjects control puff volume by 
varying the duration, mostly by truncating the latter part of 
the puff. 
IMPACT OF CHANGING 
paramf:ters of the ftc 
I ES I ME I HOD ON ABSOELITE 
YIELDS OF A CIGAREITE 
liKAND AND RELATIVE 
YIELDS OF DIFFERENT BRANDS 
Schlotzhauer and Chortyk (1983) examined the 
influence of varying smoking machine parameters 
on yields of tar, nicotine, and other selected 
smoke constituents from an ultralow-tar cigarette. 
The smoking machine parameters were changed 
to reflect the deeper inhalation, more frequent 
puffs, and vent l)locking evident among smokers of lower yield cigarettes. 
•Specifically, volume was varied from the standard 3vS ml. to 45 ml. and 
55 ml.; frequency of {)uffs was doubled; and puff duration was increased 
from 2.0 to 3.0 seconds. Only one parameter was varied at a time; yields 
were measured with vent holes both unl)locked and completely blocked. 
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