TABLE 2.

Emission factors for carbonyls in the gas and particle phases of diesel and gasoline exhaust (Jakober et al., 2008)

	Light-duty gasoline emission factor (µg/L)		Heavy-duty diesel emission factor (µg/L)
Compound	Gas phase	Particle phase	Gas phase	Particle phase
	Aliphatics
Propanal	70	87	160	210
Butanal	1900	27	8800	500
Isobutanal		1.7		21
Pentanal	770	7.6	2100	170
Hexanal	420	3.6	7000	540
Heptanal	18	13	690	160
Octanol	35	1.2	590	35
Nonanal	390	8.1	140	260
Decanal	110	2.3	860	140
Undecanal	18		380	Det
Dodecanal	56		410	59
Tridecanal	17		380
Tetradecanal			1600
	Aliphatic ketones
2-Butanone	54	6	98
3-Pentanone		0.2	34	6.3
2-Pentanone			28	11
2-Hexanone			350	110
2-Heptanone	220	5.3	140
2-Octanone	3.9		180
2-Nonanone	2.4		740
	Unsaturated aliphatics
Acrolein	4.3	0.4	22	140
Methacrolein				38
Methyl vinyl ketone		2.1	210	310
Crotonaldehyde	2.5	1.5	29	41
t-2-methyl-2-butenal	0.5
3-methyl-2-butenal	7.5	0.5	83	37
t-2-hexanal				3.6
4-hexen-3-one	1.2	0.3	14	5.7
5-hexen-2-one			4.9
	Cyclic aliphatics
2-methyl-2-cyclopentenone	0.7	0.1	27
3-methyl-2-cyclopentenone	1.6		89	16
2-cyclohexenone	2	Det	41	34
	Aliphatic dicarbonyls
Glyoxal	21	7.9	140	170
Methyl glyoxal	550	46	4200	1400
2,3-Butanedione		0.4
2,3(& 2,4)-Pentanedione		Det	3	2.1
2,3-Hexanedione	55	32	3200	1200
2,5-Hexanedione	23	4.1	290	110
	Aromatic aldehydes
Benzaldehyde	9.7	9.5	660	130
o(& m)-tolualdehyde	11	4.3	210	1.9
p-tolualdehyde	26	4	180	2.8
t-Cinnamaldehyde			36
3,4,-Methyl-benzaldehyde	19		100
2-Ethyl-benzaldehyde			130
4-Ethyl-benzaldehyde	14		500
1-Naphthaldehyde	9.3		230
2-Naphthaldehyde	10		380
4-Biphenylcarboxaldehyde			100
	Aromatic ketones
Acetaphenone	4	1.2	230	1.8
1-Indanone	5.7		75
9-Fluorenone	2.9	0.3	190	24
Benzophenone	1.7	0.7	88	20
Perinaphthenone			38	43
Xanthone				5
	Aromatic dicarbonyls
1,2-Acetylbenzene	11		49
1,3-Acetylbenzene	7.9		130
1,4-Acetylbenzene	2		28
1,8-Naphthalic anhydride				130

Bold type highlights those substances that are potentially useful biomarkers of diesel exhaust exposure.