Appendix C	Statewide Air Quality and Health Risk										Table C-17					

Annual Average Concentrations and Health Risks																
TAC	Conc.*/Risk**	1990	1991	1992	1993	1994	1995	1996	1997	1998	1999	2000	2001	2002	2003	2004
Acetaldehyde	Annual Avg	1.73	1.97	1.54	1.76	1.52	0.61	1.34	1.16	1.08	1.29	1.00	1.10	1.18	1.19	1.12
	Health Risk	8	10	7	9	7	3	7	6	5	6	5	5	6	6	5
Benzene	Annual Avg	2.57	2.14	1.71	1.50	1.58	1.31	0.93	0.85	0.86	0.85	0.71	0.61	0.63	0.57	0.46
	Health Risk	238	198	158	139	146	121	86	79	80	79	66	56	58	52	43
"1,3-Butadiene"	Annual Avg	0.41	0.34	0.32	0.39	0.34	0.31	0.26	0.23	0.25	0.23	0.18	0.17	0.17	0.12	0.11
	Health Risk	155	128	120	147	129	117	98	88	92	85	69	65	65	44	40
Carbon Tetrachloride	Annual Avg	0.13	0.13		0.11		0.10	0.08		0.11		0.09	0.09	0.09	0.09	
	Health Risk	35	34		28		26	21		30		25	23	24	25	
"Chromium, Hexavalent"	Annual Avg			0.27	0.22	0.21	0.29	0.13	0.12	0.11	0.11	0.13	0.13	0.10	0.09	0.10
	Health Risk			40	33	31	43	20	18	17	17	19	19	15	14	16
para-Dichlorobenzene	Annual Avg		0.14	0.14	0.14	0.13	0.14	0.12	0.14			0.12	0.14	0.16	0.16	0.16
	Health Risk		9	9	9	9	9	8	9			8	9	11	11	11
Formaldehyde	Annual Avg	2.18	2.07	1.65	2.08	2.18	2.93	3.38	2.89	2.64	3.20	2.55	3.18	3.50	3.15	2.69
	Health Risk	16	15	12	15	16	22	25	21	19	24	19	23	26	23	20
Methylene Chloride	Annual Avg	1.09	1.27	0.75	0.93	0.79	0.77	0.66	0.66	0.62	0.66	0.67	0.36	0.28	0.28	0.25
	Health Risk	4	4	3	3	3	3	2	2	2	2	2	1	1	1	<1
Perchloroethylene	Annual Avg	0.28	0.27	0.21	0.27	0.18	0.17	0.13	0.12	0.11		0.12	0.09	0.08	0.06	0.05
	Health Risk	11	11	8	11	7	7	5	5	5		5	4	3	2	2
Diesel PM***	Annual Avg	(2.5)					(1.6)					(1.2)				
	Health Risk	(750)					(480)					(360)				
Average Statewide Health Risk		467	409	359	394	348	350	272	228	250	212	217	207	208	178	136

"*    Concentrations for Hexavalent Chromium are expressed as ng/m3, and concentrations for Diesel PM are expressed as ug/m3.  Concentrations for all other TACs are expressed as ppb."																
**  Health Risk represents the number of excess cancer cases per million people based on a lifetime (70-year) exposure to the annual average concentration.  Total Health Risk represents only those compounds listed in																
this table and only those with data for that year.  There may be other significant compounds for which monitoring and/or health risk information are not available.																
"*** The Diesel PM concentrations are estimates based on receptor modeling. Because data are not available for all years, Diesel PM is not included in the Average Basin Health Risk number."