PAC Database - Detailed Chemical Data
Chemical Identity
| Chemical | CAS# | UN# | Health Code Numbers | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Thallium | 7440-28-0 | 1707 |
4.01
4.08
4.05
7.01
7.00
11.00
4.09
4.10
4.07
3.08
|
|||||||||
| Formula | Synonyms | |||||||||||
| Tl | THALLIUM | |||||||||||
Physical Properties
| Mol Wt | State | MP (°C) | BP (°C) | VP (Hg) | VP (°C) | SG | LEL (ppm) |
|---|---|---|---|---|---|---|---|
| 204.38 | S | 304 | 1473 | 609 | 11.8 |
PAC Values
| PAC-1 | PAC-2 | PAC-3 |
|---|---|---|
| 0.06 | 3.3 | 20 |
| PAC-1 | PAC-2 | PAC-3 |
|---|---|---|
| 0.0072 | 0.39 | 2.4 |
Technical Basis
A review of available data sources identified exposure limits and toxicity data for this chemical, including a TLV-TWA, PEL/REL-TWA, and an IDLH. Each was evaluated using the guidelines in the TEEL handbook. The unrevised (1990) IDLH value was selected as the basis for the TEEL-3. This limit is used to calculate the TEEL-2 value in accordance with Table 3.5. The TLV-TWA exposure limit was selected as the TEEL-1 basis because it is a more preferred exposure limit than the PEL/RELs (see Table 3.1). The TLV-TWA also yielded a more conservative result.
• TEEL-1 = TLV-TWA x 3
• TEEL-2 = TEEL-3/6
• TEEL-3 = IDLH (1990)
This review generated TEEL values consistent with those published in Rev. 29A.
• TEEL-1 = TLV-TWA x 3
• TEEL-2 = TEEL-3/6
• TEEL-3 = IDLH (1990)
This review generated TEEL values consistent with those published in Rev. 29A.
References
TLV-TWA: https://www.osha.gov/chemicaldata/521
PEL/REL TWA & IDLH (1990): https://www.cdc.gov/niosh/idlh/thallium.html