Table 2

Summary statistics of nicotine concentrations by smoking behaviour

Smoking behaviour		Nicotine (μg/m³)
	(n = 48)* (%)	Median	Mean	Minimum	Maximum	SE	p Value
Participant smoking status:
Non-smokers	33 (69)	0.06	0.21	<LOD	1.81	0.07
Smokers	15 (31)	2.93	6.57	0.09	26.92	2.26	<0.0001
Number of smokers in household:
No response†	7 (15)	0.04	0.21	<LOD	1.11	0.15
0	23 (48)	0.06	0.09	<LOD	0.28	0.02
1	11 (22)	1.81	4.09	0.09	24.83	2.15
2	7 (15)	3.13	8.13	0.65	26.92	3.70	<0.0001
Visitors smoke in home:
No	32 (67)	0.07	1.07	<LOD	26.92	0.84
Yes	16 (33)	2.17	4.46	0.04	24.83	1.68	<0.0001
Smoking source:
No response†	7 (15)	0.04	0.21	<LOD	1.11	0.15
None	21 (44)	0.04	0.08	<LOD	0.28	0.02
Visitors only	2 (4)	0.18	0.18	0.11	0.26	0.08
Residents only	5 (10)	0.69	6.22	0.30	26.92	5.19
Resident and visitor smoking	13 (27)	2.93	5.45	0.09	24.83	1.98	<0.0001
Number of cigarettes smoked in home:
No response†	18 (38)	0.04	0.13	<LOD	1.11	0.06
0 cigs/day	14 (30)	0.11	0.31	0.03	2.53	0.18
1–5 cigs/day	5 (10)	1.19	2.48	0.09	7.11	1.26
6–10 cigs/day	5 (10)	1.81	1.69	0.30	3.13	0.54
11–19 cigs/day	2 (4)	9.28	9.28	2.93	15.64	6.36
⩾20 cigs/day (a pack or more)	4 (8)	15.74	14.84	0.96	26.92	6.49	<0.0001
Home classification:
Non-smoking homes‡	19 (46)	0.04	0.08	<LOD	0.28	0.02
Smoking homes¶	22 (54)	1.50	4.66	<LOD	26.92	1.65	<0.0001

*One passive nicotine sample was subject to equipment problems and was excluded from the analysis.
†Data not available for entire cohort.
‡Smoke-free homes where neither household members nor visitors smoked in the residence.
¶Homes with one or more smokers in the household, and/or smoking visitors. Includes data from smoke-free homes where signs of smoking (that is, active smoking, visible cigarettes, cigars, ashtrays with ashes, matches or lighters, and/or smoking odour) were observed during the visual inspection.