2-Butanone

Agent Name
2-Butanone
Alternative Name
Methyl ethyl ketone (MEK)
CAS Number
78-93-3
Formula
C4-H8-O
Major Category
Solvents
2-Butanone formula graphical representation
Synonyms
Methyl ethyl ketone (MEK); 2-Butanone; 3-Butanone; AI3-07540 (USDA); Acetone, methyl-; Aethylmethylketon [German]; Butanone 2 [French]; Ethyl methyl cetone [French]; Ethyl methyl ketone; Ethylmethylcetone [French]; Ethylmethylketon [Dutch]; Ketone, ethyl methyl; MEK; Meetco; Methyl acetone; Methylethyl ketone; Methylethylketone; Metiletilcetona [Spanish]; Metiletilchetone [Italian]; Metyl ethyl ketone; Metyloetyloketon [Polish]; [ChemIDplus] UN1193
Category
Ketones (<C12)
Description
Colorless liquid with a moderately sharp, fragrant, mint- or acetone-like odor; [NIOSH]
Sources/Uses
Used as a solvent for surface coatings, oils, resins, artificial leather, rubbers, and glues; usually found in mixtures with other solvents; It occurs naturally in food at low concentrations. [ACGIH]
Comments
Butanone is in the list of "Some volatile substances which may be abused by inhalation" published on the web site of the U.N. International Drug Control Programme, indicating its potential to cause narcosis in workers. [Reference #1] A skin, eye, and respiratory tract irritant; Inhalation of high concentrations can cause CNS depression; [ICSC] Causes contact urticaria; [Kanerva, p. 219] TLV Basis includes embryofetal damage. [ACGIH TLVs and BEIs]
Reference Link #1
Biomedical References

Exposure Assessment

BEI
MEK in urine = 2 mg/L; sample at end of shift; The determinant is nonspecific since it is also observed after exposure to other chemicals.
Skin Designation (ACGIH)
Yes
TLV (ACGIH)
200 ppm
STEL (ACGIH)
300 ppm
PEL (OSHA)
200 ppm
MAK
200 ppm
IDLH (NIOSH)
3000 ppm
Excerpts from Documentation for IDLHs
It has been reported that 3,000 ppm is irritating to the eyes and nose [Patty et al. 1935].
Vapor Pressure
90.6 mm Hg
Odor Threshold Low
2 ppm
Odor Threshold High
85 ppm
Lethal Concentration
LC50 (rat) = 23,500mg/m3/8H
Explanatory Notes
Detection odor threshold from AIHA (mean = 16 ppm); Flash point = 26 deg F; VP from HSDB; See 2023 "Notice of Intended Changes" for TLV; [ACGIH TLVs and BEIs]
Half Life
Blood: 49-96 minutes; urine: 4 hours; [TDR, p. 1700]
Reference Link #2
NFPA
may ignite at ambient temp

Adverse Effects

Neurotoxin
Acute solvent syndrome
Reproductive Toxin
Yes

Diseases, Processes, and Activities Linked to This Agent

Diseases

Occupational diseases associated with exposure to this agent:

Processes