Thiolactic acid

  • 2-Mercaptopropionic acid
  • 2-Mercaptopropanoic acid
Formula
CH3CH(SH)COOH
Structure
Description
An oily liquid with an unpleasant odor.
Uses
Substance is used in depilatory and hair waving prepns.

Registry Numbers and Inventories.
CAS
79-42-5
EC (EINECS/ELINCS)
201-206-5
EC Class
harmful, corrosive
R 22 34
S 26 36/37/39 45
RTECS
UF5250000
RTECS class
Other
UN (DOT)
2936
Merck
12,9476
Beilstein/Gmelin
506218
Beilstein Reference
4-03-00-00682
Canada DSL/NDSL
DSL
US TSCA
Listed
Austrailia AICS
Listed
New Zealand
Listed

Properties.
Formula
C3H6O2S
Formula mass
106.14
Melting point, °C
10 - 14
Boiling point, °C
205
Vapor pressure, mmHg
0.1 (25 C)
Density
1.193 g/cm3 (19 C)
Solubility in water
Miscible
Refractive index
1.4827 (13 C)
pKa/pKb
3.74 (pKa)
Partition coefficient, pKow
0.44
Heat of vaporization
48.7 kJ/mol

Hazards and Protection.
Storage
Keep away from sources of ignition. Store in a cool, dry place. Store in a tightly closed container. Corrosives area.
Handling
Wash thoroughly after handling. Remove contaminated clothing and wash before reuse. Avoid contact with heat, sparks and flame. Do not get on skin or in eyes. Do not ingest or inhale. Use only in a chemical fume hood.
Protection
Eyes: Wear appropriate protective eyeglasses or chemical safety goggles as described by OSHA's eye and face protection regulations in 29 CFR 1910.133 or European Standard EN166. Skin: Wear appropriate protective gloves and clothing to prevent skin exposure. Clothing: Wear appropriate protective clothing to prevent skin exposure.
Respirators
Follow the OSHA respirator regulations found in 29CFR 1910.134 or European Standard EN 149. Always use a NIOSH or European Standard EN 149 approved respirator when necessary.
Small spills/leaks
Absorb spill with inert material, (e.g., dry sand or earth), then place into a chemical waste container.
Disposal code
6
Stability
Has not been fully evaluated.
Incompatibilities
Strong oxidizing agents, strong bases, strong reducing agents.
Decomposition
Carbon monoxide, carbon dioxide, sulfur oxides (SOx), including sulfur oxide and sulfur dioxide.

Fire.
Flash Point,°C
87
Fire fighting
Wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear. Will burn if involved in a fire. To extinguish fire use water spray, dry chemical, carbon dioxide, or chemical foam.
Fire potential
May burn but does not ignite readily.
Hazards
When heated, vapors may form explosive mixtures with air: indoors, outdoors, and sewers explosion hazards. May polymerize explosively when heated or involved in a fire. Contact with metals may evolve flammable hydrogen gas. Containers may explode when heated. Runoff may pollute waterways. Substance may be transported in a molten form.
Combustion products
Fire may produce irritating, corrosive and/or toxic gases.

Health.
Exposure effects
   Ingestion
Causes gastrointestinal tract burns. May cause perforation of the digestive tract.
   Inhalation
May cause irritation of the respiratory tract with burning pain in the nose and throat, coughing, wheezing, shortness of breath and pulmonary edema. Inhalation may be fatal as a result of spasm, inflammation, edema of the larynx and bronchi, chemical pneumonitis and pulmonary edema.
   Skin
Causes skin burns.
   Eyes
Causes eye burns. Lachrymator.

First aid
 
   Ingestion
Do NOT induce vomiting. If victim is conscious and alert, give 2-4 cupfuls of milk or water. Get medical aid immediately.
   Inhalation
Get medical aid immediately. Remove from exposure to fresh air immediately. If not breathing, give artificial respiration. If breathing is difficult, give oxygen.
   Skin
Get medical aid. Immediately flush skin with plenty of soap and water for at least 15 minutes while removing contaminated clothing and shoes.
   Eyes
Immediately flush eyes with plenty of water for at least 15 minutes, occasionally lifting the upper and lower eyelids. Get medical aid immediately.

Transport.
UN number
2936
Response guide
Hazard class
6.1
Packing Group
II
 
HS Code
2930 90 70
 
Std. Transport #
4921696