California Code of Regulations
Title 17 - Public Health
Division 3 - Air Resources
Chapter 1 - Air Resources Board
Subchapter 7 - Toxic Air Contaminants
Section 93000 - Substances Identified as Toxic Air Contaminants
Each substance identified in this section has been determined by the State Board to be a toxic air contaminant as defined in Health and Safety Code section 39655. If the State Board has found there to be a threshold exposure level below which no significant adverse health effects are anticipated from exposure to the identified substance, that level is specified as the threshold determination. If the Board has found there to be no threshold exposure level below which no significant adverse health effects are anticipated from exposure to the identified substance, a determination of "no threshold" is specified. If the Board has found that there is not sufficient available scientific evidence to support the identification of a threshold exposure level, the "Threshold" column specifies "None identified."
| Substance | Threshold Determination |
| Benzene (C6H6) | None identified |
| Ethylene Dibromide (BrCH2CH2Br; 1,2-dibromoethane) | None identified |
| Asbestos [asbestiform varieties of serpentine (chrysotile), riebeckite (crocidolite), cummingtonite-grunerite (amosite), tremolite, actinolite, and anthophyllite] | None identified |
| Dibenzo-p-dioxins and Dibenzofurans chlorinated in the 2,3,7 and 8 positions and containing 4,5,6 or 7 chlorine atoms | None identified |
| Cadmium (metallic cadmium and cadmium compounds) | None identified |
| Carbon Tetrachloride (CCl4; tetrachloromethane) | None identified |
| Ethylene Oxide (1,2-epoxyethane) | None identified |
| Methylene Chloride (CH2Cl2; Dichloromethane) | None identified |
| Trichloroethylene (CCl2CHCl; Trichloroethene) | None identified |
| Chloroform (CHCl3) | None identified |
| Vinyl chloride (C2H3Cl; Chloroethylene) | None identified |
| Inorganic Arsenic | None identified |
| Nickel (metallic nickel and inorganic nickel compounds) | None identified |
| Substance | Threshold Determination |
| Perchloroethylene (C2Cl4; Tetrachloroethylene) | None identified |
| Formaldehyde (HCHO) | None identified |
| 1,3-Butadiene (C4H6) | None identified |
| Inorganic Lead | None identified |
| Particulate Emissions from Diesel-Fueled Engines | None identified |
| Environmental Tobacco Smoke | None identified |
1. New
section filed 9-23-85; effective thirtieth day thereafter (Register 85, No.
39). For history of former subchapter 7, see Registers 84, No. 10; 83, No. 2;
81, No. 48; 77, No. 12; and 74, No. 47.
2. Amendment filed 1-14-86;
effective thirtieth day thereafter (Register 86, No. 3).
3.
Amendment filed 2-10-86; effective thirtieth day thereafter (Register 86, No.
7).
4. Amendment filed 10-9-86; effective thirtieth day thereafter
(Register 86, No. 43).
5. Amendment filed 11-25-86; effective
thirtieth day thereafter (Register 86, No. 48).
6. Amendment filed
2-23-87; effective thirtieth day thereafter (Register 87, No. 9).
7.
Amendment filed 10-8-87; operative 11-7-87 (Register 87, No. 43).
8.
Amendment filed 3-15-88; operative 4-14-88 (Register 88, No. 13).
9.
Amendment filed 7-22-88; operative 8-21-88 (Register 88, No.
31).
10. Amendment adding Methylene Chloride filed 6-7-90; operative
7-7-90 (Register 90, No. 30).
11. Amendment adding Trichloroethylene
filed 2-27-91; operative 3-29-91 (Register 91, No. 13).
12.
Amendment adding Vinyl chloride filed 5-10-91; operative 6-9-91 (Register 91,
No. 25).
13. Editorial correction, including removal of Inorganic
arsenic (Register 91, No. 25).
14. Amendment adding Chloroform filed
5-10-91; operative 6-9-91 (Register 91, No. 25).
15. Amendment
adding Inorganic Arsenic filed 6-6-91; operative 7-6-91 (Register 91, No.
26).
16. Change without regulatory effect amending Trichloroethylene
and adding Nickel filed 7-14-92 pursuant to section
100, title 1, California Code of
Regulations (Register 92, No. 29).
17. Amendment adding
Perchloroethylene filed 10-2-92; operative 11-1-92 (Register 92, No.
40).
18. Amendment adding Formaldehyde filed 3-2-93; operative
4-1-93 (Register 93, No. 10).
19. Amendment adding 1,3-Butadiene
filed 4-14-93; operative 5-14-93 (Register 93, No. 16).
20.
Editorial correction (Register 98, No. 16).
21. Amendment adding
inorganic lead filed 4-14-98; operative 5-14-98 (Register 98, No.
16).
22. Amendment adding "Particulate Emissions from Diesel-Fueled
Engines" filed 7-21-99; operative 8-20-99 (Register 99, No. 30).
23.
Amendment adding "Environmental Tobacco Smoke" filed 1-9-2007; operative
2-8-2007 (Register 2007, No. 2).
Note: Authority cited: Sections 39600, 39601 and 39662, Health and Safety Code. Reference: Sections 39650, 39660, 39661 and 39662, Health and Safety Code.
