Skip to main content
U.S. flag

An official website of the United States government

Here’s how you know

Dot gov

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

HTTPS

Secure .gov websites use HTTPS
A lock ( Lock A locked padlock ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

  • Environmental Topics
  • Laws & Regulations
  • Report a Violation
  • About EPA
IRIS
Contact Us

Isophorone

CASRN 78-59-1 | DTXSID8020759

  • IRIS Summary (PDF) (15 pp, 125 K)

On this page:

  • Key IRIS
    Values
  • Other EPA
    Information

Noncancer Assessment

Reference Dose for Oral Exposure (RfD) (PDF) (15 pp, 125 K) Last Updated: 09/01/1989

System RfD (mg/kg-day) Basis PoD Composite UF Confidence
Urinary 2 x 10 -1 Kidney pathology NOEL : 1.50 x 102
mg/kg-day
1000 Low

Reference Concentration for Inhalation Exposure (RfC) (PDF) (15 pp, 125 K) Last Updated: 03/01/1991

Information reviewed but value not estimated.

Cancer Assessment

Weight of Evidence for Cancer (PDF) (15 pp, 125 K) Last Updated: 10/01/1992

WOE Characterization Framework for WOE Characterization
C (Possible human carcinogen) Guidelines for Carcinogen Risk Assessment (U.S. EPA, 1986)
Basis:
  • Based on no data in humans; limited evidence of carcinogenicity of one tumor type in one sex of one animal species as shown by an increase of preputial gland carcinomas in male rats. The apparent renal tubular cell tumor in the male rat is associated with alpha-2u-globulin, considered to be of questionable relevance to humans.
  • This may be a synopsis of the full weight-of-evidence narrative.

Quantitative Estimate of Carcinogenic Risk from Oral Exposure (PDF) (15 pp, 125 K)

Oral Slope Factor: 9.5 x 10-4 per mg/kg-day
Drinking Water Unit Risk: 2.7 x 10-8 per µg/L
Extrapolation Method: Linearized multistage procedure, extra risk
Tumor site(s): Reproductive
Tumor type(s): Preputial gland carcinoma (NTP, 1986)


Quantitative Estimate of Carcinogenic Risk from Inhalation Exposure (PDF) (15 pp, 125 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 - Isophorone
  • eChemPortal - Isophorone

Critical Effects

Urinary
Urinary

Tumor Sites

Reproductive
Reproductive

Chemical Structure

Isophorone

Synonyms

  • Isoacetophorone
  • Isoforon
  • Isophoron
  • Isophorone
  • alpha-Isophoron
  • alpha-Isophorone
  • 3,5,5-Trimethyl-2-cyclohexenone
  • 78-59-1
  • IRIS Home
  • About IRIS
  • IRIS Recent Additions
  • IRIS Calendar
  • IRIS Assessments
  • Advanced Search
  • IRIS Program Materials
Contact Us to ask a question, provide feedback, or report a problem.
United States Environmental Protection Agency

Discover.

  • Accessibility Statement
  • Budget & Performance
  • Contracting
  • EPA www Web Snapshots
  • Grants
  • No FEAR Act Data
  • Privacy
  • Privacy and Security Notice

Connect.

  • Data.gov
  • Inspector General
  • Jobs
  • Newsroom
  • Open Government
  • Regulations.gov
  • Subscribe
  • USA.gov
  • White House

Ask.

  • Contact EPA
  • EPA Disclaimers
  • Hotlines
  • FOIA Requests
  • Frequent Questions

Follow.