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Zhao X, Meng X, Yang D, Dong S, Xu J, Chen D, Shi Y, Sun Y, Ding G. Thyroid disrupting effects and the developmental toxicity of hexafluoropropylene oxide oligomer acids in zebrafish during early development. CHEMOSPHERE 2024; 361:142462. [PMID: 38815816 DOI: 10.1016/j.chemosphere.2024.142462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Revised: 05/10/2024] [Accepted: 05/25/2024] [Indexed: 06/01/2024]
Abstract
As perfluorooctanoic acid (PFOA) alternatives, hexafluoropropylene oxide dimeric acid (HFPO-DA) and hexafluoropropylene oxide trimeric acid (HFPO-TA) have been increasingly used and caused considerable water pollution. However, their toxicities to aquatic organisms are still not well known. Therefore, in this study, zebrafish embryos were exposed to PFOA (0, 1.5, 3 and 6 mg/L), HFPO-DA (0, 3, 6 and 12 mg/L) and HFPO-TA (0, 1, 2 and 4 mg/L) to comparatively investigate their thyroid disrupting effects and the developmental toxicity. Results demonstrated that waterborne exposure to PFOA and its two alternatives decreased T4 contents, the heart rate and swirl-escape rate of zebrafish embryos/larvae. The transcription levels of genes related to thyroid hormone regulation (crh), biosynthesis (tpo and tg), function (trα and trβ), transport (transthyretin, ttr), and metabolism (dio1, dio2 and ugt1ab), were differently altered after the exposures, which induced the thyroid disrupting effects and decreased the heart rate. In addition, the transcription levels of some genes related to the nervous system development were also significantly affected, which was associated with the thyroid disrupting effects and consequently affected the locomotor activity of zebrafish. Therefore, HFPO-DA and HFPO-TA could not be safe alternatives to PFOA. Further studies to uncover the underlying mechanisms of these adverse effects are warranted.
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Affiliation(s)
- Xiaohui Zhao
- College of Environmental Science and Engineering, Dalian Maritime University, Dalian 116026, China
| | - Xianghan Meng
- College of Environmental Science and Engineering, Dalian Maritime University, Dalian 116026, China
| | - Dan Yang
- College of Environmental Science and Engineering, Dalian Maritime University, Dalian 116026, China
| | - Shasha Dong
- College of Environmental Science and Engineering, Dalian Maritime University, Dalian 116026, China
| | - Jianhui Xu
- College of Environmental Science and Engineering, Dalian Maritime University, Dalian 116026, China
| | - Dezhi Chen
- College of Environmental Science and Engineering, Dalian Maritime University, Dalian 116026, China
| | - Yawei Shi
- College of Environmental Science and Engineering, Dalian Maritime University, Dalian 116026, China
| | - Ya Sun
- College of Environmental Science and Engineering, Dalian Maritime University, Dalian 116026, China
| | - Guanghui Ding
- College of Environmental Science and Engineering, Dalian Maritime University, Dalian 116026, China.
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Renyer A, Ravindra K, Wetmore BA, Ford JL, DeVito M, Hughes MF, Wehmas LC, MacMillan DK. Dose Response, Dosimetric, and Metabolic Evaluations of Replacement PFAS Perfluoro-(2,5,8-trimethyl-3,6,9-trioxadodecanoic) Acid (HFPO-TeA). TOXICS 2023; 11:951. [PMID: 38133352 PMCID: PMC10747602 DOI: 10.3390/toxics11120951] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Revised: 10/20/2023] [Accepted: 11/18/2023] [Indexed: 12/23/2023]
Abstract
Few studies are available on the environmental and toxicological effects of perfluoroalkyl ether carboxylic acids (PFECAs), such as GenX, which are replacing legacy PFAS in manufacturing processes. To collect initial data on the toxicity and toxicokinetics of a longer-chain PFECA, male and female Sprague Dawley rats were exposed to perfluoro-(2,5,8-trimethyl-3,6,9-trioxadodecanoic) acid (HFPO-TeA) by oral gavage for five days over multiple dose levels (0.3-335.2 mg/kg/day). Clinically, we observed mortality at doses >17 mg/kg/day and body weight changes at doses ≤17 mg/kg/day. For the 17 mg/kg/day dose level, T3 and T4 thyroid hormone concentrations were significantly decreased (p < 0.05) from controls and HFPO-TeA plasma concentrations were significantly different between sexes. Non-targeted analysis of plasma and in vitro hepatocyte assay extractions revealed the presence of another GenX oligomer, perfluoro-(2,5-dimethyl-3,6-dioxanonanoic) acid (HFPO-TA). In vitro to in vivo extrapolation (IVIVE) parameterized with in vitro toxicokinetic data predicted steady-state blood concentrations that were within seven-fold of those observed in the in vivo study, demonstrating reasonable predictivity. The evidence of thyroid hormone dysregulation, sex-based differences in clinical results and dosimetry, and IVIVE predictions presented here suggest that the replacement PFECA HFPO-TeA induces a complex and toxic exposure response in rodents.
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Affiliation(s)
- Aero Renyer
- Oak Ridge Institute for Science and Education (ORISE), Oak Ridge, TN 37830, USA;
| | - Krishna Ravindra
- Oak Ridge Associated Universities (ORAU), Oak Ridge, TN 37830, USA;
| | - Barbara A. Wetmore
- Center for Computational Toxicology and Exposure, Office of Research and Development, U.S. Environmental Protection Agency (EPA), Durham, NC 27709, USA; (B.A.W.); (J.L.F.); (M.D.); (M.F.H.); (L.C.W.)
| | - Jermaine L. Ford
- Center for Computational Toxicology and Exposure, Office of Research and Development, U.S. Environmental Protection Agency (EPA), Durham, NC 27709, USA; (B.A.W.); (J.L.F.); (M.D.); (M.F.H.); (L.C.W.)
| | - Michael DeVito
- Center for Computational Toxicology and Exposure, Office of Research and Development, U.S. Environmental Protection Agency (EPA), Durham, NC 27709, USA; (B.A.W.); (J.L.F.); (M.D.); (M.F.H.); (L.C.W.)
| | - Michael F. Hughes
- Center for Computational Toxicology and Exposure, Office of Research and Development, U.S. Environmental Protection Agency (EPA), Durham, NC 27709, USA; (B.A.W.); (J.L.F.); (M.D.); (M.F.H.); (L.C.W.)
| | - Leah C. Wehmas
- Center for Computational Toxicology and Exposure, Office of Research and Development, U.S. Environmental Protection Agency (EPA), Durham, NC 27709, USA; (B.A.W.); (J.L.F.); (M.D.); (M.F.H.); (L.C.W.)
| | - Denise K. MacMillan
- Center for Computational Toxicology and Exposure, Office of Research and Development, U.S. Environmental Protection Agency (EPA), Durham, NC 27709, USA; (B.A.W.); (J.L.F.); (M.D.); (M.F.H.); (L.C.W.)
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