Appendix C	San Diego Air Quality and Health Risk										Table C-41				

Annual Average Concentrations and Health Risks															
TAC	Conc.*/Risk**	1990	1991	1992	1993	1994	1995	1996	1997	1998	1999	2000	2001	2002	2003
Acetaldehyde	Annual Avg	1.33	1.50	1.22	1.41	1.48	0.64	1.03	1.00	0.86	1.04	0.84	0.95	0.97	0.89
	Health Risk	6	7	6	7	7	3	5	5	4	5	4	5	5	4
Benzene	Annual Avg	2.25	1.70	1.48	1.16	1.39	0.98	0.76	0.76	0.76	0.86	0.65	0.51	0.49	0.48
	Health Risk	208	158	137	107	129	90	71	70	70	79	60	47	45	45
"1,3-Butadiene"	Annual Avg	0.33	0.26	0.26	0.31	0.31	0.24	0.21	0.20	0.20	0.22	0.16	0.14	0.12	0.09
	Health Risk	125	97	97	117	115	91	78	75	74	83	60	51	45	33
Carbon Tetrachloride	Annual Avg	0.13	0.13		0.10		0.10	0.08				0.09	0.09	0.09	0.09
	Health Risk	35	34		27		26	20				25	23	24	25
"Chromium, Hexavalent"	Annual Avg			0.24	0.19	0.16	0.18	0.11	0.11	0.10	0.10	0.10		0.05	0.05
	Health Risk			36	28	23	27	16	16	15	15	15		7	8
para-Dichlorobenzene	Annual Avg		0.10	0.11	0.13	0.15	0.12	0.11	0.13				0.15	0.15	0.15
	Health Risk		7	8	8	10	8	7	8				10	10	10
Formaldehyde	Annual Avg	1.64	1.53	1.26	1.76	2.25	2.13	2.62	2.62	2.27	2.67	2.23	2.59	2.99	2.68
	Health Risk	12	11	9	13	17	16	19	19	17	20	16	19	22	20
Methylene Chloride	Annual Avg	0.59	0.83	1.34	1.13	0.73	0.63	0.59	0.57		0.53	0.76	0.17	0.16	0.16
	Health Risk	2	3	5	4	3	2	2	2		2	3	1	1	1
Perchloroethylene	Annual Avg	0.28	0.27	0.26	0.20	0.21	0.25	0.15	0.13			0.09	0.06	0.06	0.05
	Health Risk	11	11	11	8	8	10	6	5			4	2	2	2
Diesel PM***	Annual Avg	(2.9)					(1.9)					(1.4)			
	Health Risk	(870)					(570)					(420)			
Average Basin Health Risk		399	328	309	319	312	273	224	200	180	204	187	158	161	148

"*    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."