PAC Database - Detailed Chemical Data
Chemical Identity
| Chemical | CAS# | UN# | Health Code Numbers | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Selenium | 7782-49-2 | 2658 |
15.01
4.01
11.01
14.02
4.08
7.01
8.00
11.00
4.02
4.09
|
|||||||||
| Formula | Synonyms | |||||||||||
| Se | SELENIUM POWDER, C.I. 77805, ELEMENTAL SELENIUM, SELENIO, EN POLVO (DOT SPANISH), SELENIUM, SELENIUM ALLOY, SÉLÉNIUM EN POUDRE (DOT FRENCH) | |||||||||||
Physical Properties
| Mol Wt | State | MP (°C) | BP (°C) | VP (Hg) | VP (°C) | SG | LEL (ppm) |
|---|---|---|---|---|---|---|---|
| 78.96 | S | 220.8 | 685 | 227 | 4.809 |
PAC Values
| PAC-1 | PAC-2 | PAC-3 |
|---|---|---|
| 0.60 | 17 | 100 |
| PAC-1 | PAC-2 | PAC-3 |
|---|---|---|
| 0.19 | 5.3 | 31 |
Technical Basis
A review of available sources identified the following: TLV-TWA, IDLH, and rat acute toxicity data (LC50, LD50). Data sources were selected according to the hierarchy listed in Table 3.1. Toxicity data were selected based on the 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. Inhalation doses were scaled to 60-minute equivalents using the ten Berge equation (Section 3.3.4). Considering the source preference, available hazard summaries, and conservatism, the effective IDLH (1990) was selected as the TEEL-3. The TEEL-2 was derived according to Table 3.5. The TLV-TWA was selected as the TEEL-1 basis.
• TEEL-1 = TLV-TWA (0.2 mg/m3) x 3
• TEEL-2 = TEEL-3/6
• TEEL-3 = IDLH (1990, 100 mg/m3)
This review generated TEEL-2 and TEEL-3 values less conservative than Rev. 29A. The Rev. 29A and current TEEL-1 basis and values are consistent; however, the Rev. 29A TEEL-2 and TEEL-3 were derived from this TEEL-1. Instead, the current TEEL-3 is an IDLH, a more preferred source (Table 3.1), with the TEEL-2 derived from this value.
• TEEL-1 = TLV-TWA (0.2 mg/m3) x 3
• TEEL-2 = TEEL-3/6
• TEEL-3 = IDLH (1990, 100 mg/m3)
This review generated TEEL-2 and TEEL-3 values less conservative than Rev. 29A. The Rev. 29A and current TEEL-1 basis and values are consistent; however, the Rev. 29A TEEL-2 and TEEL-3 were derived from this TEEL-1. Instead, the current TEEL-3 is an IDLH, a more preferred source (Table 3.1), with the TEEL-2 derived from this value.
References
General chemical information: https://pubchem.ncbi.nlm.nih.gov/compound/Selenium
IDLH: https://www.cdc.gov/niosh/idlh/7782492.html
TLV-TWA: https://www.osha.gov/chemicaldata/649
Rat oral LD50: https://www.atsdr.cdc.gov/ToxProfiles/tp92.pdf
Rat oral LC50: https://echa.europa.eu/da/registration-dossier/-/registered-dossier/15204/7/3/3