Table 1. Subject information.

	Nonsmokers (20)	Smokers
No. of subjects	8	12
Age, years	38 ± 6	41 ± 6
Gender	6 M/2 F	10 M/2 F
Race	7 AA/1 CA	6 AA/6 CA
Cigarettes per day		24.6 ± 9.6
Smoking years		22 ± 7.5
Cotinine, ng/ml		348 ± 99
CO, ppm		28 ± 16

M, male; F, female. AA, African American; CA, Caucasian.