Peering through the mist: systematic review of what the chemistry of contaminants in electronic cigarettes tells us about health risks

Table 1 Exposure predictions based on analysis of aerosols generated by smoking machines: volatile organic compounds

Compound	N^#	Estimated concentration in personal breathing zone		Ratio of most stringent TLV (%)		Reference
Compound	N^#	PPM	mg/m³	Calculated directly	Safety factor 10	Reference
Acetaldehyde	1	0.005		0.02	0.2	[5]
	3	0.003		0.01	0.1	[4]
	12	0.001		0.004	0.04	[8]
	1	0.00004		0.0001	0.001	[3]
	1	0.0002		0.001	0.008	[3]
	150	0.001		0.004	0.04	[40, 41]
	1	0.008		0.03	3	[38]
Acetone	1	0.002		0.0003	0.003	[38]
Acetone	150	0.0004		0.0001	0.001	[40, 41]
Acrolein	12	0.001		1	13	[8]
	150	0.002		2	20	[40, 41]
	1	0.006		6	60	[38]
Butanal	150	0.0002		0.001	0.01	[40, 41]
Crotonaldehyde	150		0.0004	0.01	0.1	[40, 41]
Formaldehyde	1	0.002		0.6	6	[5]
	3	0.008		3	30	[4]
	12	0.006		2	20	[8]
	1	<0.0003		<0.1	<1	[3]
	1	0.0003		0.1	1	[3]
	150	0.01		4	40	[40, 41]
	1	0.009		3	30	[38]
Glyoxal	1		0.002	2	20	[38]
Glyoxal	150		0.006	6	60	[40, 41]
o-Methylbenzaldehyde	12		0.001	0.05	0.5	[8]
p,m-Xylene	12		0.00003	0.001	0.01	[8]
Propanal	3	0.002		0.01	0.1	[4]
	150	0.0006		0.002	0.02	[40, 41]
	1	0.005		0.02	0.2	[38]
Toluene	12	0.0001		0.003	0.03	[8]
Valeraldehyde	150		0.0001	0.0001	0.001	[40, 41]