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				1.55	1.11	0.54	1.15	1.17	0.96	1.41	0.89	1.1	1.33	1.14	1.32	1.4	1
	Health Risk				8	5	3	6	6	5	7	4	5	6	6	6	7	5
Benzene	Annual Avg				1.1	1.14	0.85	0.67		0.55	0.64	0.52	0.499	0.544	0.449	0.533	0.427	0.297
	Health Risk				102	106	78	62		51	59	48	46	50	42	49	40	28
"1,3-Butadiene"	Annual Avg				0.295	0.249	0.205	0.216		0.17	0.149	0.142	0.157	0.154	0.111	0.132	0.108	0.057
	Health Risk				111	94	77	81		64	56	54	59	58	42	50	41	21
Carbon Tetrachloride	Annual Avg				0.108		0.1	0.079					0.088	0.087	0.093			
	Health Risk				29		26	21					23	23	24			
"Chromium, Hexavalent"	Annual Avg				0.15	0.13	0.16	0.1	0.1	0.1	0.1	0.1	0.1	0.058	0.048	0.075	0.058	0.038
	Health Risk				23	19	24	16	15	15	15	15	15	9	7	11	9	6
para-Dichlorobenzene	Annual Avg				0.1	0.13	0.1	0.12					0.13	0.15	0.15	0.15	0.15	0.15
	Health Risk				7	8	7	8					9	10	10	10	10	10
Formaldehyde	Annual Avg				2.08	1.78	2.04	2.99	3.42	2.63	4.15	2.76	3.25	4.47	3.82	3.4	3.28	2.63
	Health Risk				15	13	15	22	25	19	31	20	24	33	28	25	24	19
Methylene Chloride	Annual Avg				0.81	0.5	0.53	0.58					0.36	0.09	0.07	0.08	0.09	0.07
	Health Risk				3	2	2	2					1	<1	<1	<1	<1	<1
Perchloroethylene	Annual Avg				0.057	0.265	0.047	0.049					0.024	0.024	0.015	0.014	0.028	0.011
	Health Risk				2	11	2	2					<1	1	<1	<1	1	<1
Diesel PM	Annual Avg																	
	Health Risk																	
Total Health Risk					300	258	234	220	46	154	168	141	182	190	159	151	131	89
																		

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