Table 3.

Selected Mean (Standard Error of the Mean) Toxicant Yields per Session for Singleton and Dyad Conditions

Toxicant	Yield per user
	Singleton	Dyad	Cigarette
Nicotine, mg	1.67 (0.28)	2.63 (0.27)	0.73 47
Carbon monoxide, mg	123 (24.7)	179 (23.1)	12.0 47
Nitric oxide, µg	287 (51.2)	438 (54.4)	218.1 49
Benzo(a)pyrene, ng	153 (30.0)	220 (27.3)	6.6 48
Formaldehyde, µg	36 (11)	39 (7.0)	20.6 49

Data are not adjusted to account for the volume of smoke generated. Cigarette data from previous studies shown for comparison.