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Methyl ethyl ketone (MEK)

CASRN 78-93-3 | DTXSID3021516

  • Toxicological Review (PDF) (152 pp, 570 K)
  • IRIS Summary (PDF) (33 pp, 211 K)

On this page:

  • Key IRIS
    Values
  • Other EPA
    Information

Noncancer Assessment

Reference Dose for Oral Exposure (RfD) (PDF) (33 pp, 211 K) Last Updated: 09/26/2003

System RfD (mg/kg-day) Basis PoD Composite UF Confidence
Developmental 6 x 10 -1 Decreased pup body weight LED 5 : 639
mg/kg-day
1000 Low

Reference Concentration for Inhalation Exposure (RfC) (PDF) (33 pp, 211 K) Last Updated: 09/26/2003

System RfC (mg/m3) Basis PoD Composite UF Confidence
Developmental, Musculoskeletal 5 Developmental toxicity (skeletal variations) LEC (HEC): 1517
mg/m3
300 Medium

Cancer Assessment

Weight of Evidence for Cancer (PDF) (33 pp, 211 K) Last Updated: 09/26/2003

WOE Characterization Framework for WOE Characterization
Data are inadequate for an assessment of human carcinogenic potential Revised Draft Guidelines for Carcinogen Risk Assessment (U.S. EPA, 1999)
Basis:
  • Under the draft revised guidelines for carcinogen risk assessment (U.S. EPA, 1999), EPA concludes the data are inadequate for an assessment of human carcinogenic potential of MEK. Studies of humans chronically exposed to MEK are inconclusive, and MEK has not been tested for carcinogenicity in animals by the oral or inhalation routes.
  • This may be a synopsis of the full weight-of-evidence narrative.

Quantitative Estimate of Carcinogenic Risk from Oral Exposure (PDF) (33 pp, 211 K)

Not assessed under the IRIS Program.

Quantitative Estimate of Carcinogenic Risk from Inhalation Exposure (PDF) (33 pp, 211 K)

Not assessed under the IRIS Program.

Other EPA Information

Additional EPA toxicity information may be available by visiting the following sites:
  • Human Health Benchmarks for Pesticides (HHBP). This database provides human health benchmarks for pesticides that may be present in drinking water.
  • Office of Pesticide Programs Pesticide Chemical Search. This database provides links to health effects information and registration status for pesticides.
  • Chemistry Dashboard. This database provides information on chemical structures, experimental and predicted physicochemical, and toxicity data.

Related Links

  • EPA Chemicals Dashboard - Methyl ethyl ketone (MEK)
  • eChemPortal - Methyl ethyl ketone (MEK)

Critical Effects

Developmental
Developmental

Musculoskeletal
Musculoskeletal

Chemical Structure

Methyl ethyl ketone (MEK)

Synonyms

  • Aethylmethylketon
  • Butanone-2
  • Ethyl methyl cetone
  • Ethyl methyl ketone
  • Ethylmethylketon
  • Ketone, ethyl methyl
  • Meetco
  • Mek
  • Methyl acetone
  • Methyl ethyl ketone
  • Metiletilchetone
  • Metyloetyloketon
  • RCRA Waste Number U159
  • UN 1193
  • UN 1232
  • 2-Butanone
  • 78-93-3
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