Methyl ethyl ketoxime

Synonyms

2-Butanone oxime; Butanone oxime; Ethyl methyl ketone oxime; Ethyl methyl ketoxime; Ethyl-methylketonoxim [Czech]; MEK-oxime; Methyl ethyl ketone oxime; Skino #2; Troykyd anti-skin B; [ChemIDplus] MEKO; [AIHA] UN1993

Category

Oximes

Description

Colorless liquid with a musty odor; [CAMEO]

Sources/Uses

Used as an anti-skinning agent in alkyd paints; Also used as a blocking agent (urethane polymers) and a corrosion inhibitor (boilers); [AIHA]

Comments

A skin sensitizer; [Quick CPC] Dermal sensitization, hemolytic anemia, and CNS depression reported in animal studies; Hemolytic effects were seen in a 4-week inhalation study at 533 ppm, but not at 283 ppm; MEKO has been produced since 1958, and no adverse effects in workers have been reported; Painters using alkyd paints containing MEKO were exposed at levels <1-2 ppm; [AIHA] 8-hour exposure of 12 rats to saturated atmosphere caused no mortalities; Hematological changes (increased methemoglobin and reticulocytes and decreased hemoglobin) observed in 4-week inhalation study of rats at 400 ppm; In a 13-week oral neurotoxicity study of rats, transient neurobehavioral changes were observed immediately following administration, but reversed by the next day; No progressive long term neurotoxicity observed; [IUCLID]

Biomedical References

0.904 mm Hg

LC50 (rat) > 1350 ppm/4hr

Explanatory Notes

LC50 (rat) > 50,000 mg/m3/4hr; [ChemIDplus] The Guide in the Emergency Response Guidebook is for "Flammable liquid, n.o.s."

high ambient temp required

10 ppm

Hemolytic anemia

Yes

MetHgb is secondary toxic effect

Other CNS neurotoxin

Diseases

Occupational diseases associated with exposure to this agent:

• Contact dermatitis, allergic

Processes

Industrial Processes with risk of exposure:

• Painting (Pigments, Binders, and Biocides)