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HERO ID
5381282
Reference Type
Journal Article
Title
Development of an oral reference dose for the perfluorinated compound GenX
Author(s)
Thompson, CM; Fitch, SE; Ring, C; Rish, W; Cullen, JM; Haws, LC
Year
2019
Is Peer Reviewed?
Yes
Journal
Journal of Applied Toxicology
ISSN:
0260-437X
EISSN:
1099-1263
Volume
39
Issue
9
Page Numbers
1267-1282
Language
English
PMID
31215065
DOI
10.1002/jat.3812
Web of Science Id
WOS:000481847900003
Abstract
Ammonium 2,3,3,3-tetrafluoro-2-(heptafluoropropoxy)-propanoate, also known as GenX, is a processing aid used in the manufacture of fluoropolymers. GenX is one of several chemistries developed as an alternative to long-chain poly-fluoroalkyl substances, which tend to have long clearance half-lives and are environmentally persistent. Unlike poly-fluoroalkyl substances, GenX has more rapid clearance, but has been detected in US and international water sources. There are currently no federal drinking water standards for GenX in the USA; therefore, we developed a non-cancer oral reference dose (RfD) for GenX based on available repeated dose studies. The review of the available data indicate that GenX is unlikely to be genotoxic. A combination of traditional frequentist benchmark dose models and Bayesian benchmark dose models were used derive relevant points of departure from mammalian toxicity studies. In addition, deterministic and probabilistic RfD values were developed using available tools and regulatory guidance. The two approaches resulted in a narrow range of RfD values for liver lesions observed in a 2-year bioassay in rats (0.01-0.02 mg/kg/day). The probabilistic approach resulted in the lower, i.e., more conservative RfD. The probabilistic RfD of 0.01 mg/kg/day results in a maximum contaminant level goal of 70 ppb. It is anticipated that these values, along with the hazard identification and dose-response modeling described herein, should be informative for risk assessors and regulators interested in setting health-protective drinking water guideline values for GenX.
Keywords
benchmark dose (BMD) modeling; GenX; per- and polyfluoroalkyl substances (PFAS); reference dose (RfD); risk assessment
Tags
PFAS
•
Additional PFAS (formerly XAgency)
•
Expanded PFAS SEM (formerly PFAS 430)
Ammonium 4,8-dioxa-3H-perfluorononanoate
•
GenX Chemicals (CASRN 13252-13-6 and CASRN 62037-80-3)
LitSearch: GenX - Feb 2019-Oct 2019
WoS
PubMed
Additional Strategies
LitSearch: GenX Ammonium Salt - Feb 2019-Oct 2019
WoS
PubMed
•
PFAS 150
Missing 2021 searches
Literature Search August 2019
PubMed
Not prioritized for screening
Ammonium perfluoro-2-methyl-3-oxahexanoate
•
PFNA
•
Yale PFAS Liver study
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