IRIS toxicological review of perfluorohexanoic acid [PFHxA, CASRN 307-24-4] and related salts / Michelle Manente Angrish [and twenty-six others].

Format:

Book

Author/Creator:

Angrish, Michelle Manente, author.

Language:

English

Subjects (All):

Drugs--Dose-response relationship.

Drugs.

Risk assessment.

Physical Description:

1 online resource (1 PDF file (various pagings)) : illustrations

Place of Publication:

Washington, DC : Integrated Risk Information System, Center for Public Health and Environmental Assessment, Office of Research and Development, U.S. Environmental, 2023.

Summary:

Perfluorohexanoic acid (PFHxA, CASRN 307-24-4) and its related salts are members of the group per and polyfluoroalkyl substances (PFAS). This assessment applies to PFHxA as well as salts of PFHxA, including ammonium perfluorohexanoate (PFHxA-NH4, CASRN 21615-47-4), and sodium perfluorohexanoate (PFHxA-NA, CASRN 2923-26-4), and other nonmetal and alkali metal salts of PFHxA that would be expected to fully dissociate in aqueous solutions of pH ranging from 4-9 (e.g., in the human body) and not release other moieties that would cause toxicity independent of PFHxA. Notably, due to the possibility of PFHxA-independent contributions of toxicity, this assessment would not necessarily apply to nonalkali metal salts of PFHxA (e.g., silver perfluorohexanoate; CASRN 336-02-7). The synthesis of evidence and toxicity value derivation presented in this assessment focuses on the free acid of PFHxA and related ammonium and sodium salts given the currently available toxicity data.

Contents:

ABBREVIATIONS AND ACRONYMS

AUTHORS

CONTRIBUTORS

REVIEWERS

EXECUTIVE SUMMARY

1. OVERVIEW OF BACKGROUND INFORMATION AND ASSESSMENT METHODS

1.1. BACKGROUND INFORMATION ON PFHxA AND RELATED AMMONIUM AND SODIUM SALTS

1.2. SUMMARY OF ASSESSMENT METHODS

2. SUMMARY OF LITERATURE IDENTIFICATION AND STUDY EVALUATION RESULTS

2.1. LITERATURE SEARCH AND SCREENING RESULTS

2.2. STUDY EVALUATION RESULTS

3. PHARMACOKINETICS, EVIDENCE SYNTHESIS, AND EVIDENCE INTEGRATION

3.1. PHARMACOKINETICS

3.2. NONCANCER EVIDENCE SYNTHESIS AND INTEGRATION

3.3. CARCINOGENICITY

4. SUMMARY OF HAZARD IDENTIFICATION CONCLUSIONS

4.1. SUMMARY OF CONCLUSIONS FOR NONCANCER HEALTH EFFECTS

4.2. CONCLUSIONS REGARDING SUSCEPTIBLE POPULATIONS AND LIFESTAGES

4.3. SUMMARY OF CONCLUSIONS FOR CARCINOGENICITY

5. DERIVATION OF TOXICITY VALUES

5.1. HEALTH EFFECT CATEGORIES CONSIDERED (CANCER AND NONCANCER)

5.2. NONCANCER TOXICITY VALUES

5.3. CANCER TOXICITY VALUES

REFERENCES

SUPPLEMENTAL INFORMATION

APPENDIX A. SYSTEMATIC REVIEW PROTOCOL FOR THE PFAS IRIS ASSESSMENTS

APPENDIX B. BENCHMARK DOSE MODELING RESULTS

APPENDIX C. EVALUATION OF PFHXA ELIMINATION

APPENDIX D. QUALITY ASSURANCE FOR THE IRIS TOXICOLOGICAL REVIEW OF PFHXA

APPENDIX E. SUMMARY OF PUBLIC AND EXTERNAL PEER REVIEW COMMENTS AND EPA'S DISPOSITION

REFERENCES.

Notes:

Description based on publisher supplied metadata and other sources.