PAC Database - Detailed Chemical Data
Chemical Identity
| Chemical | CAS# | UN# | Health Code Numbers | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Magnesium silicate; (Florisil) | 1343-88-0 |
4.04
4.06
4.13
|
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| Formula | Synonyms | |||||||||||
Physical Properties
| Mol Wt | State | MP (°C) | BP (°C) | VP (Hg) | VP (°C) | SG | LEL (ppm) |
|---|---|---|---|---|---|---|---|
| 0 | S | 2.5 |
PAC Values
| PAC-1 | PAC-2 | PAC-3 |
|---|---|---|
| 6 | 170 | 1000 |
| PAC-1 | PAC-2 | PAC-3 |
|---|---|---|
| 0 | 0 | 0 |
Technical Basis
The current review and analysis included hydrated forms of magnesium silicate, of which, Talc is defined as magnesium silicate with an unspecified amount of water. A review of available data source identified the following: an IDLH and REL-TWA for hydrous magnesium silicate (Talc; CASRN: 14807-96-6). The IDLH for Talc was selected as the TEEL-3 basis, as the most preferred source (Table 3.1). Note that the 1990 and 1994 IDLH reported by NIOSH are equivalent. A TEEL-2 value was calculated from the TEEL-3 according to Table 3.5 of the handbook. The REL-TWA (respirable dust) was selected as the TEEL-1 basis.
• TEEL-1 = REL-TWA (2 mg/m3) x 3
• TEEL-2 = TEEL-3/6
• TEEL-3 = IDLH, 1990/1994 (1000 mg/m3)
This review generated TEEL values that are more conservative than those published in Rev. 29A. The basis for Rev. 29A was an HHR=1, which is less preferred than an IDLH, even when considering the ambiguity of the chemical of interest.
• TEEL-1 = REL-TWA (2 mg/m3) x 3
• TEEL-2 = TEEL-3/6
• TEEL-3 = IDLH, 1990/1994 (1000 mg/m3)
This review generated TEEL values that are more conservative than those published in Rev. 29A. The basis for Rev. 29A was an HHR=1, which is less preferred than an IDLH, even when considering the ambiguity of the chemical of interest.
References
https://www.sigmaaldrich.com/US/en/sds/sial/46385
IDLH and REL-TWA: https://www.cdc.gov/niosh/npg/npgd0584.html
IDLH and REL-TWA: https://www.osha.gov/chemicaldata/277