Chromium(VI)
CASRN 18540-29-9 | DTXSID7023982
- Toxicological Review (PDF) (70 pp, 195 K)
- IRIS Summary (PDF) (34 pp, 203 K)
- Status: Chromium(VI) is in step 5 at this time; see Quick Check.
Noncancer Assessment
Reference Dose for Oral Exposure (RfD) (PDF)
(34 pp, 203 K)
Last Updated: 09/03/1998
| System | RfD (mg/kg-day) | Basis | PoD | Composite UF | Confidence |
|---|---|---|---|---|---|
| Other | 3 x 10 -3 | None reported |
NOAEL
(ADJ):
2.5
mg/kg-day |
300
MF: 3 |
Low |
Reference Concentration for Inhalation Exposure (RfC) (PDF)
(34 pp, 203 K)
Last Updated: 09/03/1998
| System | RfC (mg/m3) | Basis | PoD | Composite UF | Confidence |
|---|---|---|---|---|---|
| Respiratory | 8 x 10 -6
(Chromic acid mists and dissolved Cr(VI) aerosols) |
Nasal septum atrophy |
LOAEL
(ADJ):
7.14
x 10-4 mg/m3 |
90 | Low |
| Respiratory | 1 x 10 -4
(Cr(VI) particulates) |
Lactate dehydrogenase in bronchioalveolar lavage fluid |
BMCL
10
(HEC):
3.4
x 10-2 mg/m3 |
300 | Medium |
Cancer Assessment
Weight of Evidence for Cancer (PDF)
(34 pp, 203 K)
Last Updated: 09/03/1998
| WOE Characterization | Framework for WOE Characterization |
|---|---|
| A (Human carcinogen) (Inhalation route) | Guidelines for Carcinogen Risk Assessment (U.S. EPA, 1986) |
| D (Not classifiable as to human carcinogenicity) (Oral route) | Guidelines for Carcinogen Risk Assessment (U.S. EPA, 1986) |
| Carcinogenic potential cannot be determined (Oral route) | Proposed Guidelines for Carcinogen Risk Assessment (U.S. EPA, 1996) |
| Known/likely human carcinogen (Inhalation route) | Proposed Guidelines for Carcinogen Risk Assessment (U.S. EPA, 1996) |
- Under the current guidelines (EPA, 1986), Cr(VI) is classified as Group A - known human carcinogen by the inhalation route of exposure. Carcinogenicity by the oral route of exposure cannot be determined and is classified as Group D. Under the proposed guidelines (EPA, 1996), Cr(VI) would be characterized as a known human carcinogen by the inhalation route of exposure on the following basis. The oral carcinogenicity of Cr(VI) cannot be determined. No data were located in the available literature that suggested that Cr(VI) is carcinogenic by the oral route of exposure.
- This may be a synopsis of the full weight-of-evidence narrative.
Quantitative Estimate of Carcinogenic Risk from Oral Exposure (PDF) (34 pp, 203 K)
Information reviewed but value not estimated.
Quantitative Estimate of Carcinogenic Risk from Inhalation Exposure (PDF) (34 pp, 203 K)
Inhalation Unit Risk:
1.2
x 10-2
per µg/m3
Extrapolation Method: Multistage, extra risk
Tumor site(s): Respiratory
Tumor type(s): Lung cancer (Mancuso, 1975)
Program Outlook Details
| Public Assessment Materials | Date |
|---|---|
| Problem Formulation Materials/IRIS Assessment Plan | Aug-2014 |
| Preliminary Assessment Materials/Systematic Review Protocol | Mar-2019 |
| Public Comment | Oct-2022 |
| External Peer Review | Mar-2023 |
| Post Final Assessment | TBD |
Note: Any future dates displayed in the table above should be considered estimates and are subject to change. Once the external peer review is complete, estimated dates for release of the final assessment will be published. For the latest information on the status of this assessment, please refer to the IRIS Program Outlook. To access assessment documents, meeting materials or other supporting documents related to this assessment, visit the Chemical Documents tab. For more information about the development process, visit the IRIS Process page.
Oct 2022: IRIS Toxicological Review of Hexavalent Chromium (External Review Draft, 2022) (Report)
Sep 2013: Hexavalent Chromium Workshops (2013) (Other)
Sep 2010: IRIS Toxicological Review of Hexavalent Chromium (2010 External Review Draft) (Report)
Sep 1998: IRIS Toxicological Review of Chromium VI (1998 Final) (Report)
Apr 1990: Noncarcinogenic Effects of Chromium: Update to Health Assessment Document (Report)
Sep 1984: Health Effects Assessment for Hexavalent Chromium (1984 Final) (Report)
Aug 1983: Health Assessment Document for Chromium (1983 Final) (Report)
- 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.
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Quick Check
Critical Effect Systems
Tumor Sites
Chemical Structure for
Chromium(VI)
