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			0.78		0.92	0.36	0.59										
	Health Risk			4		4	2	3										
Benzene	Annual Avg		1.92	1.54	1.76	1.7	1.44	1										
	Health Risk		177	143	163	157	133	92										
"1,3-Butadiene"	Annual Avg		0.272	0.26	0.393	0.308	0.3	0.251										
	Health Risk		102	98	148	116	113	94										
Carbon Tetrachloride	Annual Avg		0.123		0.11		0.097	0.078										
	Health Risk		33		29		25	21										
"Chromium, Hexavalent"	Annual Avg			0.19		0.15	0.26	0.13										
	Health Risk			28		23	39	19										
para-Dichlorobenzene	Annual Avg		0.14	0.12	0.12	0.1	0.12	0.19										
	Health Risk		9	8	8	7	8	13										
Formaldehyde	Annual Avg			1.08		1.32	2.22	4.27										
	Health Risk			8		10	16	31
Methylene Chloride	Annual Avg		0.62	0.54	0.67	0.5	0.54	0.65
	Health Risk		2	2	2	2	2	2
Perchloroethylene	Annual Avg		0.147	0.093	0.092	0.056	0.043	0.03
	Health Risk		6	4	4	2	2	1
Diesel PM	Annual Avg							
	Health Risk							
Total Health Risk			329	295	354	321	340	276
								

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