California Air Resources Board 2008 Almanac (web)																		
Annual Average Concentrations and Health Risks																		
TAC	Conc.1/Risk2	1990	1991	1992	1993	1994	1995	1996	1997	1998	1999	2000	2001	2002	2003	2004	2005	2006
Acetaldehyde	Annual Avg	2.68	2.78	2.5	2.89	2.35	1.28	2.33			1.43	0.84	1.45	1.3	1.39	1.24	1.84	1.19
	Health Risk	13	13	12	14	11	6	11			7	4	7	6	7	6	9	6
Benzene	Annual Avg	3.5	3.25	2.97	2.54	2.45	2.24	1.86		1.36	1.5	1.04	1.03		0.853	0.677	0.722	
	Health Risk	324	301	275	235	227	207	173		126	139	97	95		79	63	67	
"1,3-Butadiene"	Annual Avg	0.6	0.547	0.643	0.733	0.588	0.599	0.542		0.421	0.432	0.296	0.313		0.186	0.195	0.164	
	Health Risk	226	206	242	276	221	225	204		158	162	111	118		70	73	62	
Carbon Tetrachloride	Annual Avg	0.138	0.134				0.103	0.079		0.112		0.098	0.086		0.095			
	Health Risk	36	35				27	21		30		26	23		25			
"Chromium, Hexavalent"	Annual Avg				0.24	0.27	0.23	0.17			0.11	0.13		0.133	0.07		0.125	0.105
	Health Risk				36	40	35	25			16	19		20	11		19	16
para-Dichlorobenzene	Annual Avg		0.19	0.22	0.19	0.16	0.19	0.12				0.16	0.17		0.16	0.17	0.15	
	Health Risk		13	14	12	10	13	8				11	11		10	11	10	
Formaldehyde	Annual Avg	3.5	3	2.3	3.23	3.54	4.13	5.87			3.88	2.42	4.3	4.32	3.79	5.69	6.64	6.69
	Health Risk	26	22	17	24	26	30	43			29	18	32	32	28	42	49	49
Methylene Chloride	Annual Avg	1.28	2.72	0.68	1.05	1.06	1.51	1.1		0.8	1.2	0.68	0.74		0.59	0.5	0.44	
	Health Risk	4	9	2	4	4	5	4		3	4	2	3		2	2	2	
Perchloroethylene	Annual Avg	0.551	0.603	0.536	0.588	0.503	0.574	0.502		0.232		0.187	0.177		0.109	0.088	0.087	
	Health Risk	22	24	21	24	20	23	20		9		7	7		4	4	3	
Diesel PM	Annual Avg																	
	Health Risk																	
Total Health Risk		651	623	583	625	559	571	509		326	357	295	296	58	236	201	221	71