PAC Database - Detailed Chemical Data
Chemical Identity
| Chemical | CAS# | UN# | Health Code Numbers | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Hydroxy-2-methylpropanoic acid, 2-; (2-Methyllactic acid) | 594-61-6 |
4.01
11.01
14.01
15.02
|
||||||||||
| Formula | Synonyms | |||||||||||
| C4.H8.O3 | ||||||||||||
Physical Properties
| Mol Wt | State | MP (°C) | BP (°C) | VP (Hg) | VP (°C) | SG | LEL (ppm) |
|---|---|---|---|---|---|---|---|
| 104.11 | S | 82.5 | 212 |
PAC Values
| PAC-1 | PAC-2 | PAC-3 |
|---|---|---|
| 12 | 130 | 790 |
| PAC-1 | PAC-2 | PAC-3 |
|---|---|---|
| 2.8 | 31 | 190 |
Technical Basis
A review of available sources did not identify acute toxicity data or exposure limits for 2-hydroxy-2-methylpropanoic acid. Reported GHS health hazard ratings (H318, Category 1; H315, Category 2; H335, inhalation Category 3) indicate a mid-level health hazard, approximately equivalent to an HHR=2. Considering this, analysts assumed an HHR=2 as the TEEL-3 basis (Section 3.4.5). TEEL-2 and TEEL-1 values were derived according to Table 3.5.
• PAC-1 = TEEL-1 = TEEL-2/11
• PAC-2 = TEEL-2 = TEEL-3/6
• PAC-3 = TEEL-3 = HHR=2
This review generated PAC values inconsistent with Rev. 29A. The Rev. 29A TEEL-1 basis was a TLV-TWA for particles not otherwise specified (Section 3.5.2), from which the TEEL-2 and TEEL-3 were derived (Table 3.5). The current TEEL-3 basis is an assumed HHR=2, from analysis of GHS health hazard statements, from which TEEL-2 and TEEL-1 were derived (Table 3.5).
• PAC-1 = TEEL-1 = TEEL-2/11
• PAC-2 = TEEL-2 = TEEL-3/6
• PAC-3 = TEEL-3 = HHR=2
This review generated PAC values inconsistent with Rev. 29A. The Rev. 29A TEEL-1 basis was a TLV-TWA for particles not otherwise specified (Section 3.5.2), from which the TEEL-2 and TEEL-3 were derived (Table 3.5). The current TEEL-3 basis is an assumed HHR=2, from analysis of GHS health hazard statements, from which TEEL-2 and TEEL-1 were derived (Table 3.5).
References
Chemical information and GHS health hazard ratings retrieved from: https://pubchem.ncbi.nlm.nih.gov/compound/2-Hydroxyisobutyric-acid