Toxicological Review of Perfluorohexanoic Acid (Pfhxa) and Related Salts (Interagency Science Discussion Draft, 2023)
Alert
Notice - This site contains archived material(s)
Archive disclaimer
Archived files are provided for reference purposes only.
The file was current when produced, but is no longer maintained and may now be outdated.
Persons with disabilities having difficulty accessing archived files may contact the Risk Webmaster for assistance.
Please use the contact us form if you need additional support.
Abstract
In April 2023, EPA finalized the IRIS Toxicological Review of Perfluorohexanoic Acid (PFHxA) and Related Salts. The Toxicological Review was reviewed internally by EPA and by other federal agencies and White House Offices after public release in February 2022. Consistent with the May 2009 IRIS assessment development process, all written comments on IRIS assessments submitted by other federal agencies and White House Offices are made publicly available on this site.Perfluorohexanoic Acid (PFHxA) and its related salts are members of the group of per and polyfluoroalkyl substances (PFAS). Concerns about PFHxA and other PFAS stem from the resistance of these compounds to hydrolysis, photolysis, and biodegradation, which leads to their persistence in the environment. PFAS are not naturally occurring in the environment; they are man-made compounds that have been used widely over the past several decades in consumer products and industrial applications because of their resistance to heat, oil, stains, grease, and water.
PFHxA is a breakdown product of other PFAS that are used in stain-resistant fabrics, paper food packaging, and carpets; it is also used for manufacturing photographic film, and it is used as a substitute for longer chain perfluoroalkyl carboxylic acids (PFCAs) in consumer products. PFHxA has been found to accumulate in agricultural crops and has been detected in household dust, soils, food products, and surface, ground, and drinking water.
As such, exposure is possible via inhalation of indoor or outdoor air, ingestion of drinking water and food, and dermal contact with PFHxA-containing products.
Impact/Purpose
EPA is undertaking an update of the Integrated Risk Information System (IRIS) health assessment for PFHxA and it's related salts. The outcome of this project is an IRIS Toxicological Review and Executive Summary for PFHxA that will be entered into the IRIS database.Status
Now that the interagency review draft has been completed and finalized, the PFHxA assessment has been loaded into the IRIS Web site and Database.Citation
U.S. EPA. Toxicological Review of Perfluorohexanoic Acid (Pfhxa) and Related Salts (Interagency Science Discussion Draft, 2023). U.S. Environmental Protection Agency, Washington, DC, EPA/635/R-23/021, 2023.History/Chronology
| Date | Description |
|---|---|
| 01- Nov 2019 | EPA released the Systematic Review Protocol for the PFAS IRIS Assessment (Preliminary Assessment Materials). [Federal Register Notice Nov 8, 2019] |
| 02- Jul 2020 | EPA released an update to the Systematic Review Protocol for the PFBA, PFHxA, PFHxS, PFNA, and PFDA IRIS Assessments in response to public comments. |
| 03- Aug 2021 | EPA sent an interagency science consultation PFHxA draft for review and comment. |
| 04- Feb 2022 | EPA released the draft IRIS Toxicological Review of Perfluorohexanoic Acid (PFHxA) and Related Salts for a 60-day public comment period and external peer review. EPA also released the interagency science consultation documents, comments from reviewers, and EPA's response to major comments. [Federal Register Notice: Feb 2, 2022 ] |
| 05- Aug 2022 | EPA posted the final peer review report from the contractor on the EPA website. |
| 06- Feb 2023 | EPA submitted the revised interagency science discussion draft for final Agency and Interagency review. |
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.
- 1. ATSDR PFHxA IASD Comments March 2023 (PDF) (1 pp, 134.8 KB, about PDF)
- 2. DOD PFHxA IASD Comments March 2023 (PDF) (1 pp, 205.1 KB, about PDF)
- 3. EOP PFHxA IASD Comments March 2023 (PDF) (1 pp, 125.0 KB, about PDF)
- 4. FDA PFHxA IASD Comments March 2023 (PDF) (3 pp, 143.6 KB, about PDF)
- 5. NIEHS PFHxA IASD Comments March 2023 (PDF) (2 pp, 192.4 KB, about PDF)
- 6. NIOSH PFHxA IASD Comments March 2023 (PDF) (3 pp, 181.6 KB, about PDF)
- 7. USDA PFHxA IASD Comments March 2023 (PDF) (1 pp, 135.7 KB, about PDF)
Related Link(s)
- Systematic Review Protocol for the PFAS IRIS Assessments (2021)
- Systematic Review Protocol for the Perfluorohexanoic Acid (PFHxA) IRIS Assessment (Preliminary Assessment Materials, 2019)
- IRIS Toxicological Review of Perfluorohexanoic Acid (PFHxA) and Related Salts (Public Comment and External Review Draft, 2022)
- External Peer Review Activities for PFHxA Integrated Risk Information System (IRIS) Assessment (Feb 2022)
- Toxicological Review of Perfluorohexanoic Acid (PFHxA) and Related Salts (Final Report, 2023)