Table 2.

List of compounds analyzed in cigarettes and HTPs and their exposure limit considered for MOE determination

Compound	IEL (mg/m3)	IEL Origin	Cigarettes	HTPs	ECs
Acetaldehyde	9.0 × 10–3	EPA	✓	✓	✓
Acrolein	2.0 × 10–5	EPA	✓	✓	✓
Formaldehyde	9.0 × 10–3	OEHHA	✓	✓	✓
1,3-Butadiene	2.0 × 10–3	EPA	✓	✓	✓
Acrylonitrile	2.0 × 10–3	EPA	✓	✓	✓
Arsenic	1.5 × 10–5	OEHHA	✓	✓	✓
Cadmium	2.0 × 10–5	OEHHA	✓	✓	✓
Chromium	2.0 × 10–4	OEHHA	✓	✓	✓
Mercury	3.0 × 10–5	OEHHA	✓	✓	✓
Nickel	1.4 × 10–5	OEHHA	✓	✓	✓
Vinyl chloride	2.0 × 10–3	ECHA		✓	✓
Ammonia	2.0 × 10–1	OEHHA	✓	✓	✓
Hydrogen cyanide	9.0 × 10–3	OEHHA	✓	✓	✓
Benzene	3.0 × 10–3	OEHHA	✓	✓	✓
Toluene	3.0 × 10–1	OEHHA	✓	✓	✓
Methyl ethyl ketone	5.0 × 100	EPA	✓	✓	✓
m-Cresol	7.5 × 10–1	ECHA		✓	✓
o-Cresol	7.5 × 10–1	ECHA	✓	✓	✓
p-Cresol	7.5 × 10–1	ECHA		✓	✓
m + p-Cresol	7.5 × 10–1	ECHA	✓
Phenol	2.0 × 10–1	OEHHA	✓	✓	✓
Benzo[a]pyrene	2.0 × 10–6	EPA	✓	✓	✓
Isoprene	8.4 × 100	ECHA	✓	✓	✓
Propionaldehyde	8.0 × 10–3	EPA	✓	✓	✓
Acrylamide	6.0 × 10–3	EPA		✓	✓
Ethylene oxide	3.0 × 10–2	OEHHA		✓	✓
Selenium	1.5 × 10–2	ECHA	✓	✓	✓
Styrene	9.0 × 10–1	OEHHA	✓	✓	✓
Acetone	2.0 × 10+2	ECHA	✓	✓	✓
Propylene oxide	3.0 × 10–2	EPA		✓	✓
Pyridine	6.0 × 10–1	ECHA	✓	✓	✓
Catechol	3.0 × 10–1	ECHA	✓	✓	✓
Hydroquinone	1.1 × 100	ECHA	✓	✓	✓
Resorcinol	1.4 × 100	ECHA	✓	✓	✓
Nicotine	5.6 × 10–3	ECHA	✓	✓	✓

OEHHA: California Office of Environmental Health Hazard Assessment; EPA: U.S. Environmental Protection Agency; ECHA:European Chemicals Agency; IEL: inhalation exposure limits; HTP: heated tobacco product; EC: electronic cigarette