Table 1

Concentration of metals leached from unsmoked cigarette material measured after specified period of soaking

	Unsmoked cigarette material, μg/g
	Al	Ba	Cd	Cr	Cu	Fe	Mn	Ni	Pb	Sr	Ti	Zn
1 day
Mean value	5.94	6.45	0.130	0.326	3.74	13.8	46.4	0.480	1.36	14.1	0.603	11.1
Error^*	±0.73	±0.46	±0.02	±0.019	±0.38	±1.8	±4.2	±0.07	±0.10	±1.7	±0.037	±1.1
Minimum value	5.13	5.76	0.105	0.306	3.23	12.0	41.8	0.387	1.24	11.7	0.559	9.9
Maximum value	7.49	7.05	0.166	0.360	4.38	17.9	54.8	0.585	1.54	15.6	0.671	13.1
RSD (%)	12	6.6	19	5.1	9.8	13	8.7	15	7.2	12	5.4	9.6
n	9	9	7	8	9	9	9	9	9	10	11	9
7 days
Mean value	6.94	10.1	0.123	0.372	1.58	30.3	54.0	0.554	1.53	20.2	0.712	11.6
Error^*	±0.36	±0.8	±0.010	±0.014	±0.18	±3.4	±3.4	±0.044	±0.06	±0.8	±0.027	±0.6
Minimum value	6.52	8.9	0.114	0.361	1.39	23.3	49.7	0.483	1.46	19.4	0.686	10.3
Maximum value	7.39	10.9	0.140	0.385	1.83	33.4	57.7	0.611	1.61	21.1	0.741	12.3
RSD (%)	4.3	6.9	8.0	2.5	11	11	5.6	7.5	3.0	2.7	2.6	4.8
n	7	8	5	11	9	9	10	8	11	9	9	9
34 days
Mean value	6.90	15.3	0.132	0.283	0.67	75.3	59.6	0.404	1.79	32.8	0.729	9.68
Error^*	±0.3	±1.3	±0.038	±0.105	±0.20	±5.7	±2.9	±0.231	±0.40	±1.5	±0.036	±0.71
Minimum value	6.59	13.8	0.092	0.197	0.48	69.2	55.8	0.171	1.34	31.8	0.689	8.82
Maximum value	7.27	18.2	0.176	0.429	1.12	84.7	62.2	0.755	2.55	35.2	0.775	10.7
RSD (%)	4.2	8.1	29	37	30	7.0	3.9	57	22	3.5	4.1	6.8
n	8	9	7	10	10	9	10	9	9	9	9	11

↵* Error represents square root of the sum of the squared relative errors of the mean concentration (1σ) and mass.
RSD, relative standard deviation.