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THIOGLYCOLIC ACID
| CAS # | 68-11-1 |
|---|---|
| Formula |
C₂H₄O₂S |
| Synonyms |
Acetyl mercaptan; Mercaptoacetate; Mercaptoacetic acid; 2-Mercaptoacetic acid; 2-Thioglycolic acid; Thiovanic acid |
| Physical description | Colorless liquid with a strong, disagreeable odor characteristic of mercaptans. | ||
|---|---|---|---|
| Boiling point | 248°F at 20 mmHg | Molecular weight | 92.12 |
| Freezing point/melting point | 2.3°F | Vapor pressure | 10 mmHg at 64°F |
| Flash point | 235°F | Vapor density | |
| Specific gravity | 1.33 | Ionization potential | |
| Lower explosive limit (LEL) | 5.9% | Upper explosive limit (UEL) | |
| NFPA health rating | NFPA fire rating | ||
| NFPA reactivity rating | NFPA special instruction | ||
| Vapor hazard ratio (VHR) | |||
| Historical exceedance percentage | |||
| Target organs | |||
| Analyte code (IMIS no.) | |||
|---|---|---|---|
| Sampling group | |||
| Sampler/Sampling media | |||
| Sampling time* | |||
| Sampling volume (TWA)* | |||
| Sampling flow rate (TWA)* | |||
| Sampling volume (STEL/Peak/C)* | |||
| Sampling flow rate (STEL/Peak/C)* | |||
| Analytical method instruments | |||
| Method reference | |||
| Notes | |||
| Special requirements |
* All sampling instructions above are recommended guidelines for OSHA Compliance Safety and Health Officers (CSHOs), please see the corresponding OSHA method reference for complete details.
| Wipe Sampler/Sampling media | |
|---|---|
| Bulk Method |
| Device | |||||
|---|---|---|---|---|---|
| Model/Type | |||||
|
Sampling information (see manufacturer instructions) |
|
OSHA PEL
8-hour TWA (ST) STEL (C) Ceiling Peak |
NIOSH REL
Up to 10-hour TWA (ST) STEL (C) Ceiling |
ACGIH TLV©
8-hour TWA (ST) STEL (C) Ceiling |
|||||
|---|---|---|---|---|---|---|---|
| PEL-TWA | REL-TWA |
1 ppm (4 mg/m³) |
TLV-TWA |
1 ppm [2017] |
PEL-TWA |
1 ppm (3.8 mg/m³) |
|
| PEL-STEL | REL-STEL | TLV-STEL | PEL-STEL | ||||
| PEL-C | REL-C | TLV-C | PEL-C | ||||
| Skin notation |
NA |
Skin notation |
Y |
Skin notation |
Y |
Skin notation |
Y |
|
Notes:
Not established |
Notes: |
Notes:
dermal sensitization (DSEN) |
Notes: | ||||
| Health factors: See NIH-NLM PubChem. | IDLH | ||||||
| Carcinogenic classifications: | Notes: | ||||||
| AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3: | |||||||
Additional Resources and Literature References
|
NOAA: CAMEO Chemicals - Thioglycolic acid NIOSH: Pocket Guide to Chemical Hazards - Thioglycolic acid Literature References
|
Last Updated Date : 01/13/2021