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

Chromium(VI)

CASRN 18540-29-9 | DTXSID7023982

  • Toxicological Review (PDF)  (538  pp, 9.6 MB, about PDF)
  • IRIS Summary (PDF)  (14  pp, 461.9 KB, about PDF)
  • Key IRIS
    Values
  • Organ/System
    Specific Values
  • Chemical
    Documents
  • Report
    Details
  • Other EPA
    Information

IRIS Toxicological Review of Hexavalent Chromium (External Review Draft, 2022)

On this page:

  • Overview
  • Background
  • Downloads

Alert
Alert Notice

EPA’S Science Advisory Board (SAB) released a final report of their review of the 2022 draft IRIS Toxicological Review of Hexavalent Chromium. The report can be found on the SAB website here: Review of EPA’s draft IRIS Toxicological Review of Hexavalent Chromium (Report number EPA-SAB-23-009).

Overview

In October 2022, EPA publicly released the draft hexavalent chromium assessment for review and comment. The IRIS Toxicological Review of Hexavalent Chromium provides the scientific support and rationale for the hazard and dose-response assessment of exposure to hexavalent chromium. Following public comment, the assessment will undergo an independent external scientific peer review managed by EPA’s Science Advisory Board (SAB).

Background

Cr(VI) is a naturally occurring metal that has been most commonly used commercially to prevent rust and corrosion and can be found in a variety of industries, including pigment manufacturing, chrome plating, and stainless-steel production. The general population may be exposed to Cr(VI) compounds when they inhale ambient air, and ingest water or food containing Cr(VI). EPA’s previous IRIS assessment on Cr(VI) was posted in 1998. This new draft assessment updates the information based on the latest science. The draft assessment provides a comprehensive systematic review of hundreds of studies on cancer and multiple noncancer health effects of inhalation and oral exposure to Cr(VI), resulting in a state-of-the-science human health assessment.

History/Chronology
Date Description
Apr 2014 EPA released preliminary meeting materials for chromium (VI), part 1, in preparation for the June 2014 Bimonthly Public Science Meeting.
Jun 2014 EPA hosted a public science meeting to discuss preliminary meeting materials for chromium (VI), part 1.
Aug 2014 EPA released preliminary meeting materials for chromium (VI), part 2, in preparation for the October 2014 Bimonthly Public Science Meeting.
Oct 2014 EPA hosted a public science meeting to discuss preliminary meeting materials for chromium (VI), part 2.
Mar 2019 EPA released the Systematic Review Protocol for the Hexavalent Chromium IRIS Assessment (Preliminary Assessment Materials). [Federal Register Notice Mar 15, 2019]
Apr 2019 EPA announced that they will host a public science meeting on April 24, 2019 (by webinar) to discuss the draft document.
Feb 2022 EPA initiated an interagency science consultation on the draft IRIS Toxicological Review of Hexavalent Chromium.
Oct 2022 EPA released an update to the CrVI protocol (preliminary assessment materials), see related links for details.
Oct 2022 EPA released the draft IRIS Toxicological Review of Hexavalent Chromium (External Review Draft) for public comment and subsequent external peer review by EPA’s Science Advisory Board (SAB). Also, the EPA-led Interagency Science Consultation draft was released with comments. [Federal Register Notice Oct 20, 2022]
Dec 2024 EPA released an update to the IRIS Chloroform (inhalation) protocol.

Status

Following public comment and external peer review, the assessment will be revised prior to final posting to the IRIS Web site.

Download(s)

This download(s) is distributed solely for the purpose of pre-dissemination peer review under applicable information quality guidelines. It has not been formally disseminated by EPA. It does not represent and should not be construed to represent any Agency determination or policy.

  • IRIS Toxicological Review of Hexavalent Chromium (External Review Draft) (PDF)  (507  pp, 6.6 MB, about PDF)
  • IRIS Toxicological Review of Hexavalent Chromium - Supplemental Information (External Review Draft) (PDF)  (433  pp, 13.0 MB, about PDF)
  • Appendix A: Systematic Review Protocol for the Hexavalent Chromium IRIS Assessment (Updated Oct 2022) (PDF)  (158  pp, 2.1 MB, about PDF)
  • Review of EPA’s draft IRIS Toxicological Review of Hexavalent Chromium (Report number EPA-SAB-23-009)
  • Charge to the External Reviewers (PDF)  (8  pp, 234.4 KB, about PDF)
  • IRIS TOXICOLOGICAL REVIEW OF HEXAVALENT CHROMIUM (FINAL REPORT, 2024) (PDF)  (538  pp, 944.1 MB, about PDF)
  • An Update to the Systematic Review Protocol for the IRIS Toxicological Review of Chloroform (Inhalation) (Dec 2024) (PDF)  (151  pp, 2.5 MB, about PDF)

If you have a disability and the format of any material on our web pages interferes with your ability to access the information, please reach out to us using the Contact Us about IRIS form for assistance. To enable us to respond in a manner most helpful to you, please indicate the nature of the accessibility problem, the web address of the requested material, your preferred format in which you want to receive the material (electronic format (ASCII, etc.), standard print, large print, etc.), and your contact information.

Document Related Link(s)

  • IRIS Toxicological Review of Hexavalent Chromium Part 1: Experimental Animal Studies (Preliminary Assessment Materials, 2014)
  • IRIS Toxicological Review of Hexavalent Chromium Part 2: Human, Toxicokinetic, and Mechanistic Studies (Preliminary Assessment Materials, 2014)
  • Updated Systematic Review Protocol for the Hexavalent Chromium IRIS Assessment (Preliminary Assessment Materials, 2019)
  • IRIS Toxicological Review of Hexavalent Chromium (Interagency Science Consultation Draft, 2022)

HERO Project

  • Primary Literature Search References Sorted by Author (Chromium VI)

Federal Register Notices

  • FR Notice: Oct 20, 2022

Docket

Comments on the assessment may be submitted and reviewed using the Docket ID EPA-HQ-ORD-2014-0313

Related Links

  • EPA Chemicals Dashboard - Chromium(VI)
  • eChemPortal - Chromium(VI)

Critical Effect Systems

Developmental
Developmental

Gastrointestinal
Gastrointestinal

Hematologic
Hematologic

Hepatic
Hepatic

Respiratory
Respiratory

Tumor Sites

Gastrointestinal
Gastrointestinal

Respiratory
Respiratory

Chemical Structure for
Chromium(VI)

Chromium(VI)

Synonyms

  • Chromic ion
  • Chromium
  • Chromium (VI)
  • Chromium (VI) ion
  • Chromium, ion
  • 18540-29-9
  • 7440-47-3
  • 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.
Last updated on August 15, 2024
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.