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Acetylsalicylic acid

Synonyms & Trade Names
2-Acetoxybenzoic acid, o-Acetoxybenzoic acid, Aspirin
CAS No.
50-78-2
RTECS No.
DOT ID & Guide
Formula
CH₃COOC₆H₄COOH
Conversion
IDLH
N.D.
See: IDLH INDEX
Exposure Limits
NIOSH REL
TWA 5 mg/m3
OSHA PEL
none See Appendix G
Measurement Methods
NIOSH 0500
See: NMAM or OSHA Methods
Physical Description
Odorless, colorless to white, crystal-line powder. [aspirin] [Note: Develops the vinegar-like odor of acetic acid on contact with moisture.]
Molecular Weight
180.2
Boiling Point
284°F (Decomposes)
Melting Point
275°F
Solubility
(77°F): 0.3%
Vapor Pressure
0 mmHg (approx)
Ionization Potential
NA
Specific Gravity
1.35
Flash Point
NA
Upper Explosive Limit
NA
Lower Explosive Limit
NA
Minimum Explosive Concentration
40 g/m3
Combustible Powder; explosion hazard if dispersed in air.
Incompatibilities & Reactivities
Solutions of alkali hydroxides or carbonates, strong oxidizers, moisture [Note: Slowly hydrolyzes in moist air to salicyclic & acetic acids.]
Exposure Routes
inhalation, ingestion, skin and/or eye contact
Symptoms
irritation eyes, skin, upper respiratory system; increased blood clotting time; nausea, vomiting; liver, kidney injury
Target Organs
Eyes, skin, respiratory system, blood, liver, kidneys
Personal Protection/Sanitation
(See protection codes)
Skin:Prevent skin contact
Eyes:Prevent eye contact
Wash skin:When contaminated
Remove:No recommendation
Change:Daily
Provide:Eyewash, Quick drench
First Aid
(See procedures)
Eye:Irrigate immediately
Skin:Soap wash
Breathing:Respiratory support
Swallow:Medical attention immediately
Respirator Recommendations
See also
INTRODUCTION   ICSC CARD: 0822
Page last reviewed: October 30, 2019