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	1.29			1.37	1.04	0.39	1.03	1.05	0.92	1.23	0.83	0.74	1.14	1.04	1.09	1.15	0.92
	Health Risk	6			7	5	2	5	5	4	6	4	4	6	5	5	6	4
Benzene	Annual Avg	2.02	1.88	1.35	1	1.02	0.8	0.56	0.55	0.5	0.56	0.45	0.422	0.443	0.406	0.406	0.335	0.268
	Health Risk	187	174	125	92	95	74	51	51	47	52	42	39	41	38	38	31	25
"1,3-Butadiene"	Annual Avg	0.378	0.332	0.283	0.288	0.221	0.186	0.176	0.16	0.154	0.128	0.119	0.125	0.116	0.094	0.093	0.08	0.051
	Health Risk	142	125	106	108	83	70	66	60	58	48	45	47	44	35	35	30	19
Carbon Tetrachloride	Annual Avg	0.123	0.123		0.109		0.099	0.078				0.094	0.088	0.09	0.093			
	Health Risk	33	32		29		26	21				25	23	24	25			
"Chromium, Hexavalent"	Annual Avg			0.17	0.14	0.13	0.18	0.11	0.1	0.1	0.1	0.1	0.1	0.053	0.05	0.068	0.058	0.041
	Health Risk			26	21	19	26	16	15	15	15	15	15	8	8	10	9	6
para-Dichlorobenzene	Annual Avg			0.11	0.1	0.2	0.14	0.11	0.14			0.1	0.13	0.15	0.15	0.15	0.15	0.15
	Health Risk			7	7	14	9	7	10			7	9	10	10	10	10	10
Formaldehyde	Annual Avg	1.57			1.77	1.75	1.91	2.76	2.92	2.52	3.61	2.51	2.41	3.79	3.53	2.76	2.68	2.54
	Health Risk	12			13	13	14	20	22	19	27	18	18	28	26	20	20	19
Methylene Chloride	Annual Avg	0.65	0.56	0.55	0.98	0.66	0.53	0.54	0.52		0.6	0.57	0.29	0.08	0.08	0.07	0.08	0.07
	Health Risk	2	2	2	3	2	2	2	2		2	2	1	<1	<1	<1	<1	<1
Perchloroethylene	Annual Avg	0.071	0.074	0.063	0.052	0.165	0.049	0.055	0.052			0.058	0.027	0.025	0.018	0.015	0.021	0.015
	Health Risk	3	3	3	2	7	2	2	2			2	1	1	<1	<1	<1	<1
Diesel PM3	Annual Avg	(2.5)					(1.6)					(1.2)						
	Health Risk	(750)					(480)					('360)						
Average Basin Risk	w/o Diesel PM	385	336	269	282	238	225	190	167	143	150	160	157	162	147	118	106	83
	w/ Diesel PM	(1153)					(705)					(520)						
Sacramento Valley