Thiodiglycolic acid

  • Thiodiacetic acid
  • Mercaptodiacetic acid
  • Dicarboxymethyl sulfide
  • 2,2'-Thiobis[acetic acid]
  • (Carboxymethylthio)acetic acid
Formula
S(CH2COOH)2
Structure
Description
Gray powder.
Uses
Detection of copper, lead, mercury, silver.

Registry Numbers and Inventories.
CAS
123-93-3
EC (EINECS/ELINCS)
204-663-9
EC Class
irritant
S 26 36/37/39 45
RTECS
AJ6475000
RTECS class
Other
UN (DOT)
3261
Merck
12,9467
Beilstein/Gmelin
1764392
Beilstein Reference
4-03-00-00612
Swiss Giftliste 1
G-7290
Canada DSL/NDSL
DSL
US TSCA
Listed
Austrailia AICS
Listed
New Zealand
Listed
Korea ECL
Listed

Properties.
Formula
C4H6O4S
Formula mass
150.15
Melting point, °C
128 - 131
Boiling point, °C
168 (14 torr)
Density
1.661 g/cm3
Solubility in water
Very soluble
pKa/pKb
3.25 (pKa)

Hazards and Protection.
Storage
Store in a cool, dry place. Keep container closed when not in use. Corrosives area.
Handling
All chemicals should be considered hazardous. Avoid direct physical contact. Use appropriate, approved safety equipment. Untrained individuals should not handle this chemical or its container. Handling should occur in a chemical fume hood.
Protection
Wear appropriate safety goggles, protective clothing and gloves.
Respirators
A respiratory protection program that meets OSHA's 29 CFR ß1910.134 and ANSI Z88.2 requirements or European Standard EN 149 must be followed whenever workplace conditions warrant a respirator's use.
Small spills/leaks
Evacuate area and ventilate. Wear protective equipment. If required, use an inert absrobent. Sweep up and place in an appropriate container for disposal. Wash contaminated surfaces.
Disposal code
4
Stability
Stable under normal temperatures and pressures.
Incompatibilities
Keep away from strong oxidizing agents.

Fire.
Autoignition, °C
350
Fire fighting
Wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear. Use agent most appropriate to extinguish fire.

Health.
Poison_Class
3
Exposure effects
   Ingestion
Causes chemical burns.
   Inhalation
Causes chemical burns.
   Skin
Exposures to thioglycolates for 90 days produced severe cutaneous reaction in animals tested. Acute exposures also caused reactions, but these were much less severe.
   Eyes
Causes chemical burns.

First aid
 
   Ingestion
Seek medical attention. If individual is drowsy or unconscious, do not give anything by mouth; place individual on the left side with the head down. Contact a physician, medical facility, or poison control center for advice about whether to induce vomiting. If possible, do not leave individual unattended.
   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
Remove contaminated clothing and wash exposed area thoroughly with soap and water. A physician should examine the area if irritation or pain persists.
   Eyes
Irrigate exposed eyes with copious amounts of tepid water for at least 15 minutes. If irritation, pain, swelling, lacrimation, or photophobia persist, the patient should be seen in a health care facility.

Transport.
UN number
3261
Response guide
HS Code
2930 90 70