2003 Almanac (page 448)  Table C-10  County Emissions (tons/year) for Ten Toxic Air Contaminants by Air Basin		
Salton Sea Air Basin		

TAC	Imperial	Riverside*
Acetaldehyde	95	33
Benzene	129	76
"1,3-Butadiene"	39	17
Carbon Tetrachloride	0	0
Chromium (Hexavalent)	0.04	< .01
para-Dichlorobenzene	8	17
Formaldehyde	280	102
Methylene Chloride	19	62
Perchloroethylene	26	43
Diesel PM	240	153

*  This Air Basin includes only a portion of this county.