Chapter 7 
Table 1 
Summary of absolute bioavailability of nicotine from cigarette smoking studies 
Systemic Dose 
(mg/cigarette) 
Standard 
Method 
N 
Average 
Deviation 
Range 
Reference 
1 
22 
1.04 
0.36 
0.37-1.60 
Benowitz and Jacob, 1 984a 
11 
1.00 
0.15 
0.87-1.48 
Benowitz and Jacob, 1 984b 
11 
0.90 
0.15 
— 
Benowitz and Jacob, 1 985 
2 
10 
2.29 
1.00 
0.37-3.47 
Benowitz et al., 1991 
3 
20 
0.87 
0.41 
0.22-1 .92 
Benowitz and Jacob, 1994 
the smokers' anticipation of no more cigarettes becoming available that day. 
This finding illustrates the tremendous range of nicotine intake a smoker 
has when there is a need, or an anticipated need, for nicotine. The intake 
of nicotine per cigarette in this study was double that typically consumed , 
from ad libitum daily smoking. Consistent with this observation was 
another study in which subjects tripled their intake of nicotine per cigarette 
by smoking more intensely when the number of cigarettes allowed to be 
smoked per day was limited (Benowitz et al., 1986a). " 
The third method, that is, measuring blood cotinine concentrations, J 
resulted in an estimated dose of about 0.9 mg of nicotine per cigarette, with 1 
a range of 0.22 to 1.92 mg per cigarette (Benowitz and Jacob, 1994). What is ; , 
the quantitative relationship between nicotine intake and yield? Figure 3 "j 
shows nicotine intake data from volunteer smokers studied whose plasma 
nicotine levels were measured while they smoked their usual brand of '' 
cigarettes ad libitum while in a research ward (Benowitz and Jacob, 1984a). 
There was no correlation between the FTC-measured nicotine yield and 
study-measured intake of nicotine. The only yield that turned out to be 
accurate was 1 mg, which is fortuitous because it represents the average 
consumption. Also, most smokers of nonfiltered cigarettes took in less 
nicotine than predicted from the FTC yield. People who smoked low-yield 
cigarettes took in, on average, more nicotine than predicted by FTC yield. 
It is possible that in the 1940's and 1950's, when people smoked cigarettes 
with a nominal yield of 2.5 mg or higher of nicotine, they may in fact have 
been undersmoking those cigarettes and taking in considerably less smoke 
per cigarette than they do now. That behavior might explain the change in 
lung cancer pathology over the years. That is, a change in depth of inhaling 
and intensity of smoking may affect the location of the lung tumor. 
97 
