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	1.56	1.78	1.46	1.66			1.23			1.17	0.92	1.11	1.2	1.06	1.04	1.16	0.99
	Health Risk	8	9	7	8			6			6	4	5	6	5	5	6	5
Benzene	Annual Avg	2.5	2.2	1.94	1.51		1.14	0.86	0.89	0.91	0.98	0.74	0.588	0.563	0.561	0.402	0.449	0.399
	Health Risk	231	203	179	140		106	79	82	84	91	69	54	52	52	37	42	37
"1,3-Butadiene"	Annual Avg	0.387	0.332	0.331	0.398		0.279	0.252	0.235	0.24	0.24	0.182	0.162	0.133	0.101	0.077	0.082	0.073
	Health Risk	145	125	125	150		105	95	88	90	90	68	61	50	38	29	31	28
Carbon Tetrachloride	Annual Avg	0.131	0.125				0.1	0.078				0.095	0.086	0.093	0.093			
	Health Risk	35	33				27	21				25	23	24	24			
"Chromium, Hexavalent"	Annual Avg			0.24	0.18			0.1	0.11		0.1	0.1		0.04	0.038		0.048	0.07
	Health Risk			36	26			16	17		15	15		6	6		7	11
para-Dichlorobenzene	Annual Avg			0.12	0.13		0.12	0.11	0.13				0.15	0.15	0.15	0.15	0.15	0.15
	Health Risk			8	8		8	7	8				10	10	10	10	10	10
Formaldehyde	Annual Avg	2.01	1.76	1.42	2.06			3.14			2.84	2.32	2.63	3.41	3.05	2.45	2.76	2.28
	Health Risk	15	13	10	15			23			21	17	19	25	22	18	20	17
Methylene Chloride	Annual Avg	0.59	1.07	1.87	1.25		0.7	0.61	0.52		0.52	0.87	0.19	0.18	0.18	0.14	0.14	0.17
	Health Risk	2	4	7	4		2	2	2		2	3	<1	<1	<1	<1	<1	<1
Perchloroethylene	Annual Avg	0.329	0.308	0.319	0.256		0.352	0.168	0.147			0.1	0.065	0.072	0.059	0.043	0.045	0.04
	Health Risk	13	12	13	10		14	7	6			4	3	3	2	2	2	2
Diesel PM	Annual Avg																	
	Health Risk																	
Total Health Risk		449	399	385	361		262	256	203	174	225	205	175	176	159	101	118	110