PAC Database - Detailed Chemical Data
Chemical Identity
| Chemical | CAS# | UN# | Health Code Numbers | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Isobenzan | 297-78-9 |
7.00
7.01
11.00
4.08
8.00
3.08
7.11
7.10
10.00
3.09
|
||||||||||
| Formula | Synonyms | |||||||||||
| C9H4Cl8O | ISOBENZAN, 1,3,4,5,6,7,10,10-OCTACHLORO-4,7-ENDO-METHYLENE- 4,7,8,9-TET, 1,3,4,5,6,7,8,8-OCTACHLORO-1,3,3A,4,7,7A- HEXAHYDRO-4,7-METH, 1,3,4,5,6,7,8,8-OCTACHLORO-2-OXA-3A,4,7,7A- TETRAHYDRO-4,7-M, 4,7-METHANOISOBENZOFURAN, 1,3,4,5,6,7,8,8-OCTACHLORO-1,3,3A,, 4,7-METHANOISOBENZOFURAN, 1,3,4,5,6,7,8,8-OCTACHLORO-3A,4,7,, 948, CP 14,957, ENT 25,545, ENT 25,545-X, OMTAN, SD 4402, SHELL 4402, SHELL WL 1650, TELODRIN, WL 1650 | |||||||||||
Physical Properties
| Mol Wt | State | MP (°C) | BP (°C) | VP (Hg) | VP (°C) | SG | LEL (ppm) |
|---|---|---|---|---|---|---|---|
| 411.73 | S | 0.00001 | 25 | 1.87 |
PAC Values
| PAC-1 | PAC-2 | PAC-3 |
|---|---|---|
| 0.091 | 1.0 | 6.0 |
| PAC-1 | PAC-2 | PAC-3 |
|---|---|---|
| 0.0054 | 0.059 | 0.36 |
Technical Basis
A review of available sources identified several LD50 toxicity data for various species and routes, and a Level of Concern (LOC). Data sources were selected according to the hierarchy listed in Table 3.1. Toxicity data were selected according to type of exposure, species, and route according to the hierarchies stated in Sections 3.3.1, 3.3.2, and evaluated using factors in Tables 3.2, 3.3, and 3.4. The LOC was selected as the TEEL-2; it is an exposure limit and a high priority TEEL-2 source (Table 3.1). Analysts considered available rat and dog oral LD50 toxicity data for TEEL-3 bases; however, these resulted in TEEL-3 < TEEL-2. As such, TEEL-1 and TEEL-3 values were calculated according to Table 3.5.
• TEEL-1 = TEEL-2/11
• TEEL-2 = LOC (0.001 g/m3)
• TEEL-3 = TEEL-2 x 6
This review generated TEEL values inconsistent with Rev. 29A. The Rev. 29A TEEL-3 basis was a dog LD50, from which TEEL-2 and TEEL-1 values were derived. Instead, analysts determined that an exposure limit was a more appropriate TEEL-2 (Table 3.1), from which TEEL-3 and TEEL-1 values were derived; this is accordance with Section 3.1.
• TEEL-1 = TEEL-2/11
• TEEL-2 = LOC (0.001 g/m3)
• TEEL-3 = TEEL-2 x 6
This review generated TEEL values inconsistent with Rev. 29A. The Rev. 29A TEEL-3 basis was a dog LD50, from which TEEL-2 and TEEL-1 values were derived. Instead, analysts determined that an exposure limit was a more appropriate TEEL-2 (Table 3.1), from which TEEL-3 and TEEL-1 values were derived; this is accordance with Section 3.1.
References
Chemical information: https://pubchem.ncbi.nlm.nih.gov/compound/Isobenzan.
Dog oral LD50 (1 mg/kg): Aldrin Dieldrin Endrin and Telodrin: An Epidemiological and Toxicological Study of Long-Ter Occupational Exposure, Jager, K.W., New York, Elsevier Science Pub. Co., 1970, -(88), 1970 via PubChem; https://pubchem.ncbi.nlm.nih.gov/compound/Isobenzan.
Rat oral LD50 (4800 ug/kg): Agricultural Research Service, USDA Information Memorandum., 20(13), 1966 via PubChem; https://pubchem.ncbi.nlm.nih.gov/compound/Isobenzan.
Rat oral LD50 (3 mg/kg): Lewis RJ (1996). Sax's Dangerous Properties of Industrial Materials. 9th ed. Volumes 1-3. New York, NY: Van Nostrand Reinhold via PubChem; https://pubchem.ncbi.nlm.nih.gov/compound/Isobenzan.
LOC: Retrieved from Appendix C (page C-5); https://www.epa.gov/sites/default/files/2015-09/documents/technical_guidance_for_hazard_analysis.pdf