# NIOSH Pocket Guide to Chemical Hazards
Acetylsalicyclic acid | CAS 50-78-2
CH3COOC6H4COOH | RTECS VO0700000
Synonyms & Trade Names Acetal, o-Acetoxybenzoic acid, 2-Acetoxybenzoic acid, Aspirin | DOT ID & Guide
Exposure Limits | NIOSH REL: TWA 5 mg/m3
OSHA PEL†: none
IDLH N.D. | Conversion
Physical Description Odorless, colorless to white, crystal-line powder. [aspirin] [Note: Develops the vinegar-like odor of acetic acid on contact with moisture.]
MW: 180.2 | BP: 284°F (Decomposes) | MLT: 275°F | Sol(77°F): 0.3%
VP: 0 mmHg (approx) | IP: NA |  | Sp.Gr: 1.35
Fl.P: NA | UEL: NA | LEL: NA | MEC: 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.]
Measurement Methods NIOSH 0500
Personal Protection & Sanitation 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 To be added later
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 Cancer Site Eyes, skin, respiratory system, blood, liver, kidneys
See also: INTRODUCTION