Smoking and Tobacco Control Monograph No. 7 
Smoking parameters were chosen to represent less intense smoking (17-mL, 
1-second puffs, once per minute), conditions considered to be "average" 
smoking (45-mL, 2-second puffs, twice per minute) at the time, and extreme 
("high") smoking (75-mL, 3-second puffs, three times per minute) conditions. 
These results were compared with results generated using the standard FTC 
conditions, FTC conditions with 23 mm of the butt end of each cigarette 
taped to completely occlude tip ventilation (FTC-i-), and the extreme 
conditions with the tips taped (high+). Yields under high+ conditions 
were viewed as the maximum practical yields of the cigarettes. 
The cigarettes chosen for analysis were selected by weight and pressure 
drop (the differential pressure from end to end when air is drawn through a 
cigarette at a rate of 1,050 mL per minute [equivalent to a 35-mL puff taken 
over a 2-second period]) from two cartons purchased locally; they were 
conditioned and smoked under FTC-specified environmental conditions. 
The smoke was trapped and analyzed using FTC methods except that carbon 
monoxide was determined using gas chromatography (Horton and Guerin, 
1974) rather than nondispersive infrared spectroscopy. A single-port and 
a linear four-port Filimatic smoking machine were used rather than the 
standard 20-port machine, and one to six cigarettes were smoked per port 
depending on the smoking conditions used. At least four ports of cigarettes 
were smoked per brand or condition, but the precision of the results remained 
2 to 3 times poorer than would be expected using the standard 20-port 
protocol. 
Results for tar deliveries are diagramed in Figure 2. Results for nicotine 
and carbon monoxide generally parallel those for tar (although carbon 
monoxide yields are more scattered and less systematically varied). Several 
observations are apparent. First, the trend toward decreasing yields generally 
parallels the decrease in FTC yields regardless of the conditions used for most 
products. Second, products with barely detectable yields of tar measured by 
the FTC method produce readily detectable quantities of tar when smoked 
under reasonable conditions. Third, even the lowest FTC tar products can 
yield 10 to 20 mg of tar under sufficiently aggressive smoking conditions. 
Products with very low FTC tar yields that depend largely on filter ventilation 
are those most subject to underestimation of practical yields by the FTC 
method. 
Several investigators have reported on the influence of more relevant 
combinations of smoking conditions on the yields of tar and nicotine. 
Fable 9 summarizes some of these observations for tar. Rickert and colleagues 
(1983) reported that increasing the puff volume to 48 mL and decreasing 
the puff interval to 44 seconds resulted in an increase of approximately 
40 to 90 percent in the yield of tar over that found using standard ITC 
conditions. Using the same conditions but also occluding 50 percent of the 
filter ventilation resulted in an increase of from 70 to 500 percent depending 
on the product. Percentage increase in yield tended to correlate inversely 
with yield of ITC tar; that is, the lower the ITC yield, the greater the 
{)ercentage increase. 
146 
