Annex A Tables 2 to 13
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Table 2 In vitro toxicity studies for PFSAs – PFBS
|
Substance / CAS no. / purity / reference |
Test model / replicates / Guideline (GL) study / Good Laboratory Practice (GLP) status |
Conc. (nM) / duration |
Negative ctrl / positive ctrl Cytotoxicity |
Endpoints |
Results |
Study author conclusions |
Comments |
|
PFBS CAS No. not given. Purity not given. Croce et al. (2019). |
WST-1 assay: FRTL-5 cells. 2 x 104 cells/well (96 well plate). 3 expts. No. of replicates not given. cAMP assay: No. cells not given (80% confluence). 3 expts. No. of replicates not given. Non-GL study. GLP not stated. |
0, 1 x 10-1, 1, 1 x 101, 1 x 102, 1 x 103 or 1 x 105. 24 hr.
|
6H medium. 1 mU/L TSH (cAMP assay). WST-1 assay. Not cytotoxic (data only reported in figures) up to 1 x 105 nM. |
Thyroid cell viability. TSH-stimulated cAMP production. |
No effect on inhibition of TSH-induced. cAMP production in FRTL-5 cells (data only reported in figures). |
cAMP production is not modulated by PFBS. The study excludes an interference with the TSH-dependent control of thyroid function as a mechanism by which PFBS would interfere with thyroid function. |
K2 Aim of the study was to investigate whether PFBS could affect thyroid cell viability and/or interfere with the functional effect of TSH by investigating TSH-induced cAMP production in FRTL-5 cells. Number of replicates not given. Purity not given. No details of funding given. Authors declare no conflict of interest.
|
|
PFBS CAS No. not given. Purity not given. Ren et al. (2016). |
Human WT TTR. 50 nM. Human mutant TTRmutK15G. 500 nM. 3 expt. in triplicate. Non-GL study. GLP not stated. |
Human WT and TTRmutK15G. 1 – 1 x 106 (estimated from figures). 5 minutes.
|
Competitive binding assay: NA. 50 nM F-T4. Cytotoxicity NA.
|
Binding potency to TTR. |
WT TTR. IC50 = 1.33 x 104 nM. RP = 0.002 relative to T4. TTRmutK15G No observed effect.
|
Binding affinities of TTR to PFAS were much stronger than those of TBG to the same PFAS. PFAS might bind to TTR but not TBG when ingested and enter the blood stream. Displacement of T4 from TTR may be a concern for workers occupationally exposed to PFAS but not for the general population. |
K1 Aim of the study was to investigate the binding affinities of PFAS with human TH transport proteins TTR and TBG (see below). Purity not given. Funded by the Chinese Academy of Sciences and the National Natural Science Foundation of China. Authors declared no conflicts of interest. |
|
PFBS CAS No. not given. Purity not given. Ren et al. (2016) |
Human WT TBG. 50 nM. Human mutant TBGmutR378G. 1000 nM. Human mutant. TBGmutR381G. 1000 nM. 3 expt. in triplicate. Non-GL study. GLP not stated. |
Human WT TBG, TBGmutR378G and TBGmutR381G. 1 – 1 x 106 (estimated from figures). 5 minutes.
|
NA. 50 nM F-T4. Cytotoxicity NA.
|
Binding potency to TBG. |
WT TBG. No observed effect. TBGmutR378G. No observed effect. TBGmutR381G. No observed effect.
|
Binding affinities of TTR to PFAS were much stronger than those of TBG to the same PFAS. PFAS might bind to TTR but not TBG when ingested and enter the blood stream.. |
K1 Aim of the study was to investigate the binding affinities of PFAS with human TH transport proteins TTR and TBG. Purity not given. Funded by the Chinese Academy of Sciences and the National Natural Science Foundation of China. Authors declared no conflicts of interest. |
|
PFBS CAS No. 2795-39-3. Purity not given. Weiss et al. (2009) |
TTR. 30nM. No. of expts and replicates not given. Non-GL study. GLP not stated. |
1 x 10-1 – 1 x 105 Overnight. |
NA. T4. Cytotoxicity NA. |
T4-TTR-binding. |
IC50 = 1.94 x 104 nM. RP = 0.003 relative to T4. |
Competitive binding of PFCs to TTR, as observed for human TTR in the present study with certain PFAS, may explain altered TH levels described for PFC-exposed rats and monkeys. |
K2 Aim of the study was to investigate if PFAS compete with T4 for binding to TTR. Number of replicates and experiments not given. CAS No. given is for potassium perfluorooctanesulfonate, not perfluorobutane sulfonate which is the name given in the study. Study funded by EU-supported program MODELKEY and the Marie Curie Research Training Network KEYBIOEFFECTS. |
Table 3 In vitro toxicity studies for PFSAs - PFHxS
|
Substance / CAS no. / purity / reference |
Test model / replicates / GL study / GLP status |
Conc. (nM) / duration |
Negative ctrl / positive ctrl Cytotoxicity |
Endpoints |
Results |
Study author conclusions |
Comments |
|
PFHxS CAS No. 355-46-4. 98%. Long et al. (2013). |
GH3 cells. 3 x 103 cells/well (96 well plate). 3 expts. in quadruplicate. Non-GL study. GLP not stated. |
1 - 1 x 105. 6 days. |
0.02% DMSO. 0.5 nM T3. LDH. Cytotoxic at > 1 x 106 nM. |
Thyroid hormone-dependent cell growth (T-screen assay). |
Without T3 (agonistic response). ↓ cell proliferation. LOEC = 1 nM. REP at MOEC = -4.03% relative to T3. With T3 (competitive response). ↓ T3-induced cell proliferation. LOEC = 10 nM REP at MOEC = -1.49/1.80% relative to T3. |
PFHxS has the potential to inhibit the function of the TH system. |
K2 Aim of the study was to assess the potential impacts of seven PFAS on TH activity using the rat pituitary tumour cell line GH3 expressing intracellular TR and responding to physiological concentration of TH by proliferation (named as T-screen). T-screen assay exposure duration 6 days. Study funded by the Danish Strategic Research Council and Aarhus University. |
|
PFHxS CAS No. 355-46-4. 98%. Long et al. (2013). |
Hepa1.12cR cells. 6 × 104 cells/per well. 2 expts. in triplicate. Non-GL study. GLP not stated. |
1 - 1 x 105 4 hr. |
0.02% DMSO. 60 pM TCDD. LDH. Cytotoxic at > 1 x 106 nM. |
Activation / inhibition of AhR. (AhR transcriptional activation bioassay). |
Without TCDD (agonistic response). ↓ in AhR-tact LOEC = 1 x 105 nM. AhR-REP No effect. With TCDD (competitive response). No observed effect.
|
No obvious cytotoxicity at 1 x 10-4 M measured in LDH assay. The higher concentration. (1 x 106 nM) of PFHxS elicited cytotoxicity in the cells. Thus, the decreased AhR-tact of PFHxS might be related to the starting of cytotoxicity. |
K1 Aim of the study was to assess the potential impacts of seven PFAS on AhR function. The AhR transcriptional activity was determined by AhR-luciferase reporter gene bioassay using the stably transfected mouse Hepa1.1 2cR cell. Study funded by the Danish Strategic Research Council and Aarhus University. |
|
PFHxS CAS No. not given. Purity not given. Ren et al. (2016). |
Human WT TTR 50 nM. Human mutant TTRmutK15G. 500 nM. 3 expts. in triplicate. Non-GL study. GLP not stated. |
Human WT and mutant TTRmutK15G. 1 – 1 x 106 (estimated from figures). 5 minutes.
|
Competitive binding assay: NA. 50 nM F-T4. Cytotoxicity NA.
|
Binding potency to TTR. |
WT TTR IC50 = 5.94 x 102 nM. RP = 0.053 relative to T4. TTRmutK15G. No observed effect.
|
Binding affinities of TTR to PFAS were much stronger than those of TBG to the same PFAS. PFAS might bind to TTR but not TBG when ingested and enter the blood stream. Displacement of T4 from TTR may be a concern for workers occupationally exposed to PFAS but not for the general population. |
K1 Aim of the study was to investigate the binding affinities of PFAS with human TH transport proteins TTR and TBG. Purity not given. Funded by the Chinese Academy of Sciences and the National Natural Science Foundation of China. Authors declared no conflicts of interest. |
|
PFHxS CAS No. not given. Purity not given. Ren et al. (2016) |
Human WT TBG. 50 nM. Human mutant TBGmutR378G. 1000 nM. Human mutant. TBGmutR381G. 1000 nM. 3 expts. in triplicate. Non-GL study. GLP not stated. |
Human WT TBG, mutant TBGmutR378G and mutant. TBGmutR381G. 1 – 1 x 106 (estimated from figures). 5 minutes.
|
NA. 50 nM F-T4. Cytotoxicity NA.
|
Binding potency to TBG. |
WT TBG. No observed effect. TBGmutR378G. No observed effect. TBGmutR381G. No observed effect.
|
Binding affinities of TTR to PFAS were much stronger than those of TBG to the same PFAS. PFAS might bind to TTR but not TBG when ingested and enter the blood stream. |
K1 Aim of the study was to investigate the binding affinities of PFAS with human TH transport proteins TTR and TBG. Purity not given. Funded by the Chinese Academy of Sciences and the National Natural Science Foundation of China. Authors declared no conflicts of interest. |
|
PFHxS CAS No. 3871-99-6. ≥98%. Weiss et al. (2009). |
TTR. 30nM. No. of expts. and replicates not given. Non-GL study. GLP not stated. |
1 x 101 – 1 x 104 Overnight. |
NA. T4. Cytotoxicity NA. |
T4-TTR-binding. |
IC50 = 7.17 x 102 nM. RP = 0.085 relative to T4. |
Competitive binding of PFCs to TTR, as observed for human TTR in the present study with certain PFAS, may explain altered TH levels described for PFC-exposed rats and monkeys. |
K2 Aim of the study was to investigate if PFAS compete with T4 for binding to TTR. Of the 24 PFAS studied, PFHxS had the highest potency, relative to T4. Number of experiments and replicates and not given. Study funded by EU-supported program MODELKEY and the Marie Curie Research Training Network KEYBIOEFFECTS. |
Table 4 In vitro toxicity studies for PFSAs - PFOS
|
Substance / CAS no. / purity / reference |
Test model / replicates / GL study / GLP status |
Conc. (nM) / duration |
Negative ctrl / positive ctrl Cytotoxicity |
Endpoints |
Results |
Study author conclusions |
Comments |
|
PFOS CAS No. not given. Purity not given. Conti et al. (2020). |
FRTL-5 cells. FRTL5-YFP cells. No. of cells not given. 6-9 expts. No. of replicates not given. Non-GL study. GLP not stated. |
0, 3 x 102, 1 x 103, 3 x 103, 1 x 105. 2 or 10 minutes. |
Coon’s modified nutrient mixture F-12 Ham. NaClO4. Quick Cell Proliferation Colorimetric Assay. No cytotoxicity up to 1 x 105 nM (FRTL-5 cells). |
Iodide accumulation by thyroid follicular FRTL5-YFP cells. |
↓ intracellular iodide concentration from 3 x 102 nM (150 ng/mL) (data only reported in figures).
|
PFOS inhibits NIS mediated iodide uptake by thyroid cells in vitro, although at concentrations unlikely to impact the general population. No effect on iodide efflux from thyroid cells. Disruption of iodide homeostasis in thyroid cells may be a potential mechanism for anti-thyroid health effects of PFOS. |
K2 Aim of the study was to evaluate the acute effects of PFOS on iodide transport by thyroid follicular cells in vitro. No data on the number of cells plated. Number of replicates not given. No details of funding given. Authors declare no conflicts of interest. |
|
PFOS CAS No. not given. Purity not given. Coperchini et al. (2015). |
FRTL-5 cells. 5 x 104 cells/well (6 well plate). 2 expts. in triplicate. Non-GL study. GLP not stated. |
0, 1, 1 x 101, 1 x 102, 1 x 103, 1 x 104, 1 x 105. 72 hr.
|
6H medium. NA.. Cytotoxicity. ↑ cell death at 1 x 105 nM (15.6% vs 47.5%).
|
Thyroid cell proliferation and viability. |
↓ cell proliferation at 1 x 105 nM (4.25% vs 3.9%). ↑ cell death at 1 x 105 nM (15.6% vs 47.5%).
|
At a concentration of 105 nM significant inhibition of cell proliferation mainly due to cell death. The experimental design only allows identification of an acute in vitro exposure, but the possibility that a toxic effect may be produced by prolonged in vivo exposure to even lower concentrations of PFCs cannot be ruled out. Results indicate that PFOS enters thyroid cells by a gradient-based passive diffusion mechanism. |
K1 Aim of the study was to evaluate the effect of the in vitro exposure to PFOS on thyroid cell proliferation and viability. No details of funding given. |
|
PFOS CAS No. not given. Purity not given. Coperchini et al. (2021).
|
FRTL-5 cells. WST-1 assay: 2 x 104 cells/well. (96 well plate). No. of expts. and replicates not given. Annexin V‑FITC/PI assay: 1 x 104 cells/well. (24 well plate). No. of expts. and replicates not given. Cell proliferation assay: 500 cells/well (12 well plate). No. of expts. and replicates not given Non-GL study. GLP not stated. |
WST-1 assay: 0, 2 x 10-2, 2 x 10-1, 2, 2 x 101, 2 x 102. (originally reported as 0, 0.01, 0.1, 1, 10 or 100 ng/mL). 24, 48, 72, or 144 hr. Annexin V‑FITC/PI assay: 0 or 2.0 x 102 (originally reported as 100 ng/mL). 144 hr. Cell proliferation assay: 0, 2 x 10-2, 2 x 10-1, 2, 2 x 101, 2 x 102. (originally reported as 0, 0.01, 0.1, 1, 10 or 100 ng/mL). 6 days. |
6H medium NA. WST-1 assay ↓ FRTL-5 cell viability from 2.0 x 101 nM (10 ng/mL) at 24, 48, 72, or 144 hr (data only reported in figures).
|
Cell viability Cell death (apoptosis), late apoptotic, or necrotic cells Cell proliferation. |
WST-1 assay: ↓ FRTL-5 cell viability from 2 x 101 nM (10 ng/mL) at 24, 48, 72, or 144 hr (data only reported in figures). Annexin V‑FITC/PI assay: ↑ FRTL-5 cell death (data only reported in figures). Cell proliferation assay: ↓ FRTL-5 cell proliferation from 1 nM (1 ng/mL) data only reported in figures). |
PFOS exposure reduced viability and proliferation of FRTL5 and NHT cells. |
K2 Aim of the study was to evaluate the in vitro effects of PFOS on a strain of differentiated rat-thyroid cells (FRTL5 cells) in terms of cell viability, proliferation rate, and reactive oxygen species (ROS) production, after both short and long time of exposure. No details of number of replicates or experiments given. Conversion from ng/mL based on a molecular weight of 500.13 for CAS No. 1763-23-1. Funded by Università degli Studi di Pavia. Authors declared no conflicts of interest.
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|
PFOS CAS No. not given. Purity not given. Coperchini et al. (2021).
|
NHT cells. WST-1 assay: 2 x 104 cells/well. (96 well plate). No. of expts. and replicates not given . Annexin V‑FITC/PI assay: 1 x 104 cells/well. (24 well plate). Replicates not given. Cell proliferation assay: 500 cells/well (12 well plate). Replicates not given. Non-GL study. GLP not stated. |
WST-1 assay: 0, 2 x 10-2, 2 x 10-1, 2, 2 x 101, 2 x 102. (originally reported as 0, 0.01, 0.1, 1, 10 or 100 ng/mL). 24, 48, 72, or 144 hr. Annexin V‑FITC/PI assay: 0 or 1 x 10-.1 (originally reported as100 ng/mL). 144 hr. Cell proliferation assay: 0, 2 x 10-2, 2 x 10-1, 2, 2 x 101, 2 x 102. (originally reported as 0, 0.01, 0.1, 1, 10 or 100 ng/mL). 6 days. |
6H medium. NA. WST-1 assay. ↓ NHT cell viability from 2 nM (1 ng/mL) at 24 hr, from 2.0 x 10-1 nM (0.1 ng/mL) at 24 hr, from 2.0 x 101 nM (10 ng/mL) at 72 hr and from 2.0 x 10-2 nM (0.01 ng/mL) at 144 hr (data only reported in figures).
|
Cell viability. Cell death (apoptosis), late apoptotic, or necrotic cells. Cell proliferation. |
WST-1 assay: ↓ NHT cell viability from 2.0 nM (1 ng/mL) at 24 hr, from 2 x 10-1 nM (0.1 ng/mL) at 24 hr, from 2 x 101 nM (10 ng/mL) at 72 hr and from 2 x 10-2 nM (0.01 ng/mL) at 144 hr (data only reported in figures). Annexin V‑FITC/PI assay: ↑ NHT cell death (data only reported in figures). Cell proliferation assay: ↓ NHT cell proliferation from 2 nM (1 ng/mL) (data only reported in figures). |
PFOS exposure reduced viability and proliferation of FRTL5 and NHT cells. |
K2 Aim of the study was to evaluate the in vitro effects of PFOA on primary cultures of normal human thyroid cells (NHT) in terms of cell viability, proliferation rate, and ROS production, after both short and long time of exposure. No details of number of replicates or experiments given. Conversion from ng/mL based on a molecular weight of 500.13 for CAS No. 1763-23-1. Funded by Università degli Studi di Pavia. Authors declared no conflicts of interest.
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|
PFOS CAS No. not given. Purity not given. Croce et al. (2019) |
WST-1 assay: FRTL-5 cells. 2 x 104 cells/well (96 well plate). 3 expts. No. of replicates not given, cAMP assay: No. cells not given (80% confluence). 3 expts. No. of replicates not given. Non-GL study. GLP not stated. |
1 x 10-1, 1, 1 x 101, 1 x 102, 1 x 103, 1 x 105 24 hr.
|
6H medium. 1 mU/LTSH (cAMP assay). WST-1 assay. Cytotoxic at 1 x 105 nM (data only reported in figures). |
Thyroid cell viability. TSH-stimulated cAMP production. |
No effect on inhibition of TSH-induced. cAMP production in FRTL-5 cells (data only reported in figures). |
PFOS is cytotoxic at high concentrations (rarely, if ever, observed in humans), and its effect appears to be concentration-dependent. cAMP production is not modulated by PFOS. The study excludes an interference with the TSH-dependent control of thyroid function as a mechanism by which PFOS would interfere with thyroid function. |
K2 Aim of the study was to investigate whether PFBS could affect thyroid cell viability and/or interfere with the functional effect of TSH by investigating TSH-induced cAMP production in FRTL-5 cells. Number of replicates not given. Purity not given. No details of funding given. Authors declare no conflict of interest.
|
|
PFOS CAS No. not given. Purity not given. De Toni et al. (2022).
|
FRTL-5 cells. Cell growth (MTT assay): 3-8 x 103 cells/well (96 well plate). 3 expts. in triplicate. cAMP assay: No. cells not given (80% confluence). (96 well plate). 3 expts. in triplicate. Iodide uptake assay: No. cells not given (60% confluence) (96 well plate). 3 expts. in triplicate. Non-GL study. GLP not stated. |
0, 2 x 10-1, 2, 2 x 101, 2 x 102 (originally reported as (originally reported as 0, 0.1, 1, 10 or 100 ng/mL). Cell growth: 24 hr. cAMP assay: 72h. Iodide uptake assay: 24 hr. |
Coon′s modified Ham′s F12. Medium. 1 mU/L TSH (cAMP assay). NaSCN (Iodide uptake assay). MTT assay. No effect on cytotoxicity up to 2 x 102 (100 ng/ml) (data only reported in figures). |
Cell growth and membrane fluidity. Total RNA. TSH-stimulated cAMP production. Iodide uptake. |
No effect on basal iodide uptake in cells in the absence of TSH stimulation. ↑ increase in iodide uptake in cells following TSH stimulation from 2 x 10-1 nM (0.1 ng/mL) (data only reported in figures). No effect on mean fluorescence intensity of MC540 staining (a proxy of membrane fluidity). ↓ intracellular cAMP levels at 2 x 102 (100 ng/ml) (data only reported in figures). No effect on NIS and TPO gene expression following TSH stimulation (data only reported in figures). |
Legacy and new generation PFAS can differentially influence TSH dependent signalling pathways through the direct interaction with TSH-R. Computer-Based Molecular Docking and Molecular Dynamics Analysis shows the possible interference the TSH/TSH-R interaction. |
K2 Aim of the study was to assess the potential disrupting effect of PFAS, on FRTL-5 normal rat thyroid follicular cell lines via cell function, cell toxicity, membrane biophysical properties and computational modelling of the possible interaction with TSH-Receptor. Number of replicates not given, Purity not given. Conversion from ng/mL based on a molecular weight of 500.13 for CAS No. 1763-23-1. Molecular docking studies were also conducted but no quantitative data reported. Study funded by Solvay Specialty Polymers Italy S.p.A. The funder had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data, or approval of the manuscript; and decision to submit the manuscript for publication. |
|
PFOS CAS No. 1763-23-1. 98%. Long et al. (2013). |
GH3 cells. 3 x 103 cells/well (96 well plate). 3 expts. in quadruplicate. Non-GL study. GLP not stated. |
1 – 1 x 105. 6 days. |
0.02% DMSO. 0.5 nM T3. LDH. Cytotoxic at >1 x 106. |
Thyroid hormone-dependent cell growth (T-screen assay). |
Without T3 (agonistic response). ↓ cell proliferation. LOEC = 1 nM. RPE at MOEC = -3.87% relative to T3. With T3 (competitive response). ↓ T3-induced cell proliferation. LOEC = 10 nM RPE at MOEC = -1.69% relative to T3. |
PFOS has the potential to inhibit the function of the TH system. Thus, PFOS might affect the endocrine homeostasis via interfering with nuclear receptor pathways including PPAR, ER, AR, TR and AhR. |
K2 Aim of the study was to assess in vitro the potential impacts of seven PFAS on TH activity using the rat pituitary tumour cell line GH3 expressing intracellular TR and responding to physiological concentration of TH by proliferation (named as T-screen). T-screen assay exposure duration 6 days. Study funded by the Danish Strategic Research Council and Aarhus University. |
|
PFOS CAS No. 1763-23-1. 98%. Long et al. (2013). |
Hepa1.12cR cells. 6 × 104 cells/per well. 2 expts. in triplicate. Non-GL study. GLP not stated. |
1 - 1 x 105 Duration not given. |
0.02% DMSO. 60 pM TCDD. LDH. Cytotoxic at >1 x 106. |
Activation / inhibition of AhR. (AhR transcriptional activation bioassay). |
Without TCDD (agonistic response). No observed effect. With TCDD (competitive response). No observed effect.
|
No effect on AhR. |
K1 Aim of the study was to assess in vitro the potential impacts of seven PFAS on AhR function. The AhR transcriptional activity was determined by AhR-luciferase reporter gene bioassay using the stably transfected mouse Hepa1.1 2cR cell. No data on the number of cells plated or duration of exposure. Study funded by the Danish Strategic Research Council and Aarhus University. |
|
PFOS CAS No. not given. Purity not given. Ren et al. (2016). |
Human WT TTR. 50 nM. Human mutant TTRmutK15G. 500 nM. in triplicate. Non-GL study. GLP not stated. |
Human WT and mutant TTRmutK15G. 1 – 1 x 106 (estimated from figures). 5 minutes.
|
Competitive binding assay: NA. 50 nM F-T4. Cytotoxicity NA.
|
Binding potency to TTR. |
WT TTR. IC50 = 1.30 x 102 nM. RP = 0.24 relative to T4. TTRmutK15G. IC50 = 4.31 x 104 nM.
|
Binding affinities of TTR to PFAS were much stronger than those of TBG to the same PFAS. PFAS might bind to TTR but not TBG when ingested and enter the blood stream. Displacement of T4 from TTR may be a concern for workers occupationally exposed to PFAS but not for the general population. PFOS could completely displace T4 from TTR in production workers. |
K1 Aim of the study to investigate the binding affinities of PFAS with human TH transport proteins TTR and TBG. Purity not given. Of the 16 PFAS studied, PFOS had the highest potency relative to T4 with WT TTR. Funded by the Chinese Academy of Sciences and the National Natural Science Foundation of China. Authors declared no conflicts of interest. |
|
PFOS CAS No. not given. Purity not given. Ren et al. (2016). |
Human WT TBG. 50 nM. Human mutant TBGmutR378G. 1000 nM. Human mutant. TBGmutR381G. 1000 nM. 3 expts. in triplicate. Non-GL study. GLP not stated. |
Human WT TBG, TBGmutR378G and TBGmutR381G. 1 – 1 x 106 (estimated from figures). 5 minutes.
|
NA. 50 nM F-T4. Cytotoxicity NA.
|
Binding potency to TBG. |
No observed effect. TBGmutR378G. No observed effect. TBGmutR381G. No observed effect.
|
Binding affinities of TTR to PFAS were much stronger than those of TBG to the same PFAS. PFAS might bind to TTR but not TBG when ingested and enter the blood stream. |
K1 Aim of the study to investigate the binding affinities of PFAS with human TH transport proteins TTR and TBG. Purity not given. Funded by the Chinese Academy of Sciences and the National Natural Science Foundation of China. Authors declared no conflicts of interest. |
|
PFOS CAS No. 2795-39-3. ≥98%. Weiss et al. (2009). |
TTR. 30nM. No. of expts. and replicates not given. Non-GL study. GLP not stated. |
1 x 101 – 1 x 104 . Overnight. |
NA T4. Cytotoxicity NA. |
T4-TTR-binding. |
IC50 = 9.4 x 102 nM. RP = 0.065 relative to T4. |
Competitive binding of PFCs to TTR, as observed for human TTR in the present study with certain PFAS, may explain altered TH levels described for PFC-exposed rats and monkeys. |
K2 Aim of the study was to investigate if PFAS compete with T4 for binding to TTR. Number of replicates and experiments not given. Study funded by EU-supported program MODELKEY and the Marie Curie Research Training Network KEYBIOEFFECTS. |
Table 5 In vitro toxicity studies for PFSAs – L-PFDS
|
Substance / CAS no. / purity / reference |
Test model / replicates/ GL study / GLP status |
Conc. (nM) / duration |
Negative ctrl / positive ctrl Cytotoxicity |
Endpoints |
Results |
Study author conclusions |
Comments |
|
L-PFDS CAS No. NA. ˃99%. Weiss et al. (2009). |
TTR. 30nM. No. of expts. and replicates not given. Non-GL study. GLP not stated. |
1 x 101 – 1 x 104. Overnight. |
NA. T4. Cytotoxicity NA. |
T4-TTR-binding. |
IC50 = ND. RP = ND relative to T4. |
RP not calculated due to IC50 falling below the laboratory detection limit. Competitive binding of PFCs to TTR, as observed for human TTR in the present study with certain PFAS, may explain altered TH levels described for PFC-exposed rats and monkeys. |
K2 Aim of the study was to investigate if PFAS compete with T4 for binding to TTR. Number of replicates and experiments not given. Study funded by EU-supported program MODELKEY and the Marie Curie Research Training Network KEYBIOEFFECTS. |
Table 6 In vitro toxicity studies for PFSIAs – L-PFOSi
|
Substance / CAS no. / purity / reference |
Test model / replicates / GL study / GLP status |
Conc. (nM) / duration |
Negative ctrl / positive ctrl Cytotoxicity |
Endpoints |
Results |
Study author conclusions |
Comments |
|
L-PFOSi CAS No. NA. ˃99%. Weiss et al. (2009). |
TTR. 30nM. No. of expts. and replicates not given. Non-GL study. GLP not stated. |
1 x 101 – 1 x 104 . Overnight. |
NA. T4. Cytotoxicity NA. |
T4-TTR-binding. |
IC50 = 1.73 x 103 nM. RP = 0.035 relative to T4. |
Competitive binding of PFCs to TTR, as observed for human TTR in the present study with certain PFAS, may explain altered TH levels described for PFC-exposed rats and monkeys. |
K2 Aim of the study to investigate if PFAS compete with T4 for binding to TTR. Number of replicates and experiments not given. Of the 24 PFAS studied, PFOS had the second highest potency, relative to T4. Study funded by EU-supported program MODELKEY and the Marie Curie Research Training Network KEYBIOEFFECTS. |
Table 7 In vitro toxicity studies for PFCAs – PFBA
|
Substance / CAS no. / purity / reference |
Test model / replicates / GL study / GLP status |
Conc. (nM) / duration |
Negative ctrl / positive ctrl Cytotoxicity |
Endpoints |
Results |
Study author conclusions |
Comments |
|
PFBA. CAS No. not given. Purity not given. Croce et al. (2019). |
WST-1 assay: FRTL-5 cells. 2 x 104 cells/well (96 well plate). 3 expts. No. of replicates not given. cAMP assay: No. cells not given (80% confluence). 3 expts. No. of replicates not given. Non-GL study. GLP not stated. |
0, 1 x 10-1, 1 x 10, 1 x 102, 1 x 103, 1 x 104, 1 x 105 24 hr.
|
6H medium. 1 mU/L TSH (cAMP assay). WST-1 assay. No effect on cytotoxicity (data only reported in figures). |
Thyroid cell viability. TSH-stimulated cAMP production. |
No effect on inhibition of TSH-induced cAMP production in FRTL-5 cells (data only reported in figures). |
cAMP production is not modulated by PFBA. The study excludes an interference with the TSH-dependent control of thyroid function as a mechanism by which PFBA would interfere with thyroid function. |
K2 Aim of the study was to investigate whether PFBS could affect thyroid cell viability and/or interfere with the functional effect of TSH by investigating TSH-induced cAMP production in FRTL-5 cells. Number of replicates not given. Purity not given. No details of funding given. Authors declare no conflict of interest.
|
|
PFBA CAS No. not given. Purity not given. Ren et al. (2016). |
Human WT TTR. 50 nM. Human mutant TTRmutK15G. 500 nM. 3 expts. in triplicate. Non-GL study. GLP not stated. |
Human WT and TTRmutK15G. 1 – 1 x 106 (estimated from figures). 5 minutes.
|
Competitive binding assay: NA. 50 nM F-T4. Cytotoxicity NA.
|
Binding potency to TTR. |
WT TTR. IC50 = 8.92 x 104 nM. RP = 3 x 10-4 relative to T4. TTRmutK15G. No observed effect.
|
Binding affinities of TTR to PFAS were much stronger than those of TBG to the same PFAS. PFAS might bind to TTR but not TBG when ingested and enter the blood stream. Displacement of T4 from TTR may be a concern for workers occupationally exposed to PFAS but not for the general population. |
K1 Aim of the study was to investigate the binding affinities of PFAS with human TH transport proteins TTR and TBG. Purity not given. Funded by the Chinese Academy of Sciences and the National Natural Science Foundation of China. Authors declared no conflicts of interest. |
|
PFBA CAS No. not given. Purity not given. Ren et al. (2016). |
Human WT TBG. 50 nM.
Human mutant TBGmutR378G. 1000 nM. Human mutant. TBGmutR381G. 1000 nM. 3 expts. in triplicate. Non-GL study. GLP not stated. |
Human WT TBG, TBGmutR378G and TBGmutR381G. 1 – TTRmutK15G. 1 – 1 (estimated from figures) 5 minutes.
|
NA. 50 nM F-T4. Cytotoxicity NA.
|
Binding potency to TBG. |
WT TBG No observed effect. TBGmutR378G. No observed effect. TBGmutR381G. No observed effect.
|
Binding affinities of TTR to PFAS were much stronger than those of TBG to the same PFAS. PFAS might bind to TTR but not TBG when ingested and enter the blood stream. |
K1 Aim of the study was to investigate the binding affinities of PFAS with human TH transport proteins TTR and TBG. Purity not given. Funded by the Chinese Academy of Sciences and the National Natural Science Foundation of China. Authors declared no conflicts of interest. |
|
PFBA CAS No. 375-22-4. 99%. Weiss et al. (2009). |
TTR. 30nM. No. of expts. and replicates not given. Non-GL study. GLP not stated. |
1 x 101 – 1 x 104. Overnight. |
NA. T4. Cytotoxicity NA. |
T4-TTR-binding. |
IC50 = ND. RP = ND relative to T4. |
RP not calculated due to IC50 falling below the laboratory detection limit. Competitive binding of PFCs to TTR, as observed for human TTR in the present study with certain PFAS, may explain altered TH levels described for PFC-exposed rats and monkeys. |
K2 Aim of the study was to investigate if PFAS compete with T4 for binding to TTR. Number of replicates and experiments not given. Study funded by EU-supported program MODELKEY and the Marie Curie Research Training Network KEYBIOEFFECTS. |
Table 8 In vitro toxicity studies for PFCAs – PFPeA
|
Substance / CAS no. / purity / reference |
Test model / replicates / GL study / GLP status |
Conc. (nM) / duration |
Negative ctrl / positive ctrl Cytotoxicity |
Endpoints |
Results |
Study author conclusions |
Comments |
|
PFPeA CAS No. not given. Purity not given. Croce et al. (2019). |
WST-1 assay: FRTL-5 cells. 2 x 104 cells/well (96 well plate). 3 expts. No. of replicates not given. cAMP assay: No. cells not given (80% confluence) 3 expts. No. of replicates not given. Non-GL study. GLP not stated. |
0, 1 x 10-1, 1 x 10, 1 x 102, 1 x 103, 1 x 104, 1 x 105 24 hr.
|
6H medium. 1 mU/LTSH (cAMP assay). WST-1 assay. No effect on cytotoxicity (data only reported in figures). |
Thyroid cell viability. TSH-stimulated cAMP production. |
No effect on inhibition of TSH-induced. cAMP production in FRTL-5 cells (data only reported in figures). |
cAMP production is not modulated by PFPeA. The study excludes an interference with the TSH-dependent control of thyroid function as a mechanism by which PFPeA would interfere with thyroid function. |
K2 Aim of the study was to investigate whether PFPeA could affect thyroid cell viability and/or interfere with the functional effect of TSH by investigating TSH-induced cAMP production in FRTL-5 cells. Number of replicates not given. Purity not given. No details of funding given. Authors declare no conflict of interest. |
Table 9 In vitro toxicity studies for PFCAs – PFHxA
|
Substance / CAS no. / purity / reference |
Test model / replicates / GL study / GLP status |
Conc. (nM) / duration |
Negative ctrl / positive ctrl Cytotoxicity |
Endpoints |
Results |
Study author conclusions |
Comments |
|
PFHxA CAS No. not given. Purity not given. Ren et al. (2016). |
Human WT TTR. 50 nM. Human mutant TTRmutK15G. 500 nM. 3 expts. in triplicate. Non-GL study. GLP not stated. |
Human WT and mutant TTRmutK15G. 1 – 1 x 106 (estimated from figures). 5 minutes.
|
Competitive binding assay: NA. 50 nM F-T4. Cytotoxicity NA.
|
Binding potency to TTR. |
WT TTR. IC50 = 3.19 x 103 nM. RP = 9 x 10-3 relative to T4. TTRmutK15G. No observed effect.
|
Binding affinities of TTR to PFAS were much stronger than those of TBG to the same PFAS. PFAS might bind to TTR but not TBG when ingested and enter the blood stream. Displacement of T4 from TTR may be a concern for workers occupationally exposed to PFAS but not for the general population. |
K1 Aim of the study was to investigate the binding affinities of PFAS with human TH transport proteins TTR and TBG. Purity not given. Funded by the Chinese Academy of Sciences and the National Natural Science Foundation of China. Authors declared no conflicts of interest. |
|
PFHxA CAS No. not given. Purity not given. Ren et al. (2016). |
Human WT TBG. 50 nM.
Human mutant TBGmutR378G. 1000 nM. Human mutant. TBGmutR381G. 1000 nM. 3 expts. in triplicate Non-GL study. GLP not stated. |
Human WT TBG, TBGmutR378G and TBGmutR381G. 1 – 1 x 106 (estimated from figures) 5 minutes.
|
NA. 50 nM F-T4. Cytotoxicity NA.
|
Binding potency to TBG. |
WT TBG. No observed effect. TBGmutR378G. No observed effect. TBGmutR381G. No observed effect.
|
Binding affinities of TTR to PFAS were much stronger than those of TBG to the same PFAS. PFAS might bind to TTR but not TBG when ingested and enter the blood stream. |
K1 Aim of the study was to investigate the binding affinities of PFAS with human TH transport proteins TTR and TBG. Purity not given. Funded by the Chinese Academy of Sciences and the National Natural Science Foundation of China. Authors declared no conflicts of interest. |
|
PFHxA CAS No. 307-24-4. ≥98%. Weiss et al. (2009). |
TTR. 30nM. No. of expts. and replicates not given. Non-GL study. GLP not stated. |
1 x 101 – 1 x 104. Overnight. |
NA. T4. Cytotoxicity NA. |
T4-TTR-binding. |
IC50 = 8.22 x 103 nM. RP = 0.007 relative to T4. |
Competitive binding of PFCs to TTR, as observed for human TTR in the present study with certain PFAS, may explain altered TH levels described for PFC-exposed rats and monkeys. |
K2 Aim of the study was to investigate if PFAS compete with T4 for binding to TTR. Number of replicates and experiments not given. Study funded by EU-supported program MODELKEY and the Marie Curie Research Training Network KEYBIOEFFECTS. |
Table 10 In vitro toxicity studies for PFCAs – 7H-PFHpA
|
Substance / CAS no. / purity / reference |
Test model / replicates / GL study / GLP status |
Conc. (nM) / duration |
Negative ctrl / positive ctrl Cytotoxicity |
Endpoints |
Results |
Study author conclusions |
Comments |
|
7-H PFHpA CAS No. 1546-95-8. 98%. Weiss et al. (2009). |
TTR. 30nM. No. of expts. and replicates not given. Non-GL study. GLP not stated. |
1 x 101 – 1 x 104. Overnight. |
NA. T4. Cytotoxicity NA. |
T4-TTR-binding. |
IC50 = 8.64 x 103 nM. RP = 0.007 relative to T4. |
Competitive binding of PFCs to TTR, as observed for human TTR in the present study with certain PFAS, may explain altered TH levels described for PFC-exposed rats and monkeys. |
K2 Aim of the study was to investigate if PFAS compete with T4 for binding to TTR. Number of replicates and experiments not given. Study funded by EU-supported program MODELKEY and the Marie Curie Research Training Network KEYBIOEFFECTS. |
Table 11 In vitro toxicity studies for PFCAs – 6:2 FTUA
|
Substance / CAS no. / purity / reference |
Test model / replicates / GL study / GLP status |
Conc. (nM) / duration |
Negative ctrl / positive ctrl Cytotoxicity |
Endpoints |
Results |
Study author conclusions |
Comments |
|
6:2 FTUA CAS No. NA. 98%. Weiss et al. (2009). |
TTR. 30nM. No. of expts. and replicates not given. Non-GL study. GLP not stated. |
1 x 101 – 1 x 104 . Overnight. |
NA. T4. Cytotoxicity NA. |
T4-TTR-binding. |
IC50 = 8.85 x 103 nM. RP = 0.007 relative to T4. |
Competitive binding of PFCs to TTR, as observed for human TTR in the present study with certain PFAS, may explain altered TH levels described for PFC-exposed rats and monkeys. |
K2 Aim of the study was to investigate if PFAS compete with T4 for binding to TTR. Number of experiments and replicates not given. Study funded by EU-supported program MODELKEY and the Marie Curie Research Training Network KEYBIOEFFECTS. |
Table 12 In vitro toxicity studies for PFCAs – PFHpA
|
Substance / CAS no. / purity / reference |
Test model / replicates / GL study / GLP status |
Conc. (nM) / duration |
Negative ctrl / positive ctrl Cytotoxicity |
Endpoints |
Results |
Study author conclusions |
Comments |
|
PFHpA CAS No. not given. Purity not given. Ren et al. (2016). |
Human WT TTR. 50 nM. Human mutant TTRmutK15G. 500 nM. 3 expts. in triplicate. Non-GL study. GLP not stated. |
Human WT and TTRmutK15G. 1 – 1 x 106 (estimated from figures) 5 minutes.
|
Competitive binding assay: NA. 50 nM F-T4. Cytotoxicity NA.
|
Binding potency to TTR. |
WT TTR. IC50 = 1.13 x 103 nM. RP = 0.028 relative to T4. TTRmutK15G. No observed effect.
|
Binding affinities of TTR to PFAS were much stronger than those of TBG to the same PFAS. PFAS might bind to TTR but not TBG when ingested and enter the blood stream. Displacement of T4 from TTR may be a concern for workers occupationally exposed to PFAS but not for the general population. |
K1 Aim of the study was to investigate the binding affinities of PFAS with human TH transport proteins TTR and TBG. Purity not given. Funded by the Chinese Academy of Sciences and the National Natural Science Foundation of China. Authors declared no conflicts of interest. |
|
PFHpA CAS No. not given. Purity not given. Ren et al. (2016). |
Human WT TBG 50 nM.
Human mutant TBGmutR378G. 1000 nM. Human mutant. TBGmutR381G. 1000 nM. 3 expts. in triplicate. Non-GL study. GLP not stated. |
Human WT TBG, TBGmutR378G and TBGmutR381G. 1 – 1 x 106 (estimated from figures) 5 minutes.
|
NA. 50 nM F-T4. Cytotoxicity NA.
|
Binding potency to TBG. |
WT TBG. No observed effect. TBGmutR378G. No observed effect. TBGmutR381G. No observed effect.
|
Binding affinities of TTR to PFAS were much stronger than those of TBG to the same PFAS. PFAS might bind to TTR but not TBG when ingested and enter the blood stream.. |
K1 Aim of the study was to investigate the binding affinities of PFAS with human TH transport proteins TTR and TBG. Purity not given. Funded by the Chinese Academy of Sciences and the National Natural Science Foundation of China. Authors declared no conflicts of interest. |
|
PFHpA CAS No. 375-85-9. 96%. Weiss et al. (2009). |
TTR. 30 nM. No. of expts. and replicates not given. Non-GL study. GLP not stated. |
1 x 101 – 1 x 104. Overnight. |
NA. T4. Cytotoxicity NA. |
T4-TTR-binding. |
IC50 = 1.56 x 103 nM. RP = 0.039 relative to T4. |
Competitive binding of PFCs to TTR, as observed for human TTR in the present study with certain PFAS, may explain altered TH levels described for PFC-exposed rats and monkeys. |
K2 Aim of the study was to investigate if PFAS compete with T4 for binding to TTR. Number of experiments and replicates not given. Study funded by EU-supported program MODELKEY and the Marie Curie Research Training Network KEYBIOEFFECTS. |
Table 13 In vitro toxicity studies for PFCAs – PFOA
|
Substance / CAS no. / purity / reference |
Test model / replicates / GL study / GLP status |
Conc. (nM) / duration |
Negative ctrl / positive ctrl Cytotoxicity |
Endpoints |
Results |
Study author conclusions |
Comments |
|
PFOA CAS No. not given. Purity not given. Conti et al. (2020). |
FRTL-5 cells. FRTL5-YFP cells. 6-9 expts Replicates not given. Non-GL study. GLP not stated. |
0 or 1 x 105. 2 or 10 minutes. |
Coon’s modified nutrient mixture F-12 Ham. NaClO4. Quick Cell Proliferation Colorimetric Assay. Not cytotoxic up to 1 x 105 nM. |
Iodide accumulation by thyroid follicular cells. |
No effect on intracellular iodide concentration at 1 x 105 nM (100 µM) (data only reported in figures).
|
PFOA did not inhibit NIS mediated iodide uptake by thyroid cells in vitro. |
K2 Aim of the study was to evaluate the acute effects of PFOA on iodide transport by thyroid follicular cells in vitro. No data on the number of cells plated. Number of replicates not given. No details of funding given. Authors declare no conflicts of interest. |
|
PFOA CAS No. not given. Purity not given. Coperchini et al. (2015). |
FRTL-5 cells. 5 x 104 cells/well (6 well plate). 2 expts. in triplicate. Non-GL study GLP not stated. |
0, 1, 10, 1 x 102, 1 x 103, 1 x 104, and 1 x 105. 6H medium 72 hr. |
6H medium. NA. Cytotoxicity. ↑ cell death at 105 (15.6% vs 37.9%).
|
Thyroid cell proliferation and viability. |
↓ cell proliferation at 1 x 105 nM (4.25% vs 7.5%). ↑ cell death at 1 x 105 nM (15.6% vs 37.9%).
|
At a concentration of 1 x 104 nM significant inhibition of cell proliferation mainly due to cell death. Results indicate that PFOA enters thyroid cells by a gradient-based passive diffusion mechanism. |
K1 Aim of the study was to evaluate the effect of the in vitro exposure to PFOS on thyroid cell proliferation and viability. No details of funding given. |
|
PFOA CAS No. not given. Purity not given. Coperchini et al. (2021).
|
FRTL-5 cells. WST-1 assay: 2 x 104 cells/well. (96 well plate) No. of expts. and replicates not given. Annexin V‑FITC/PI assay: 1 x 104 cells/well. (24 well plate) No. of expts. and replicates not given. Cell proliferation assay: 500 cells/well (12 well plate). No. of expts. and replicates not given. Non-GL study. GLP not stated. |
WST-1 assay: 0, 2.41 x 10-2, 2.41 x 10-1, 2.41, 2.41 x 101 or 2.41 x 102. (originally reported as 0, 0.01, 0.1, 1, 10 or 100 ng/mL). 6H medium. 24, 48, 72, or 144 hr. Annexin V‑FITC/PI assay: 0 or 2.41 x 102. (originally reported as 100 ng/mL). 6H medium. 144 hr. Cell proliferation assay: 0, 2.41 x 10-2, 2.41 x 10-1, 2.41, 2.41 x 101 or 2.41 x 102. (originally reported as 0, 0.01, 0.1, 1, 10 or 100 ng/mL). 6H medium. 6 days. |
6H medium NA. WST-1 assay. ↓ FRTL-5 cell viability from 2.41 x 101 nM (10 ng/mL) at 144 hr (data only reported in figures).
|
Cell viability. Cell death (apoptosis), late apoptotic, or necrotic cells Cell proliferation. |
WST-1 assay: ↓ FRTL-5 cell viability from 2.41 x 101 (10 ng/mL) at 144 hr (data only reported in figures). Annexin V‑FITC/PI assay: ↑ FRTL-5 cell death (data only reported in figures). Cell proliferation assay: ↓ FRTL-5 cell proliferation from 2.41 nM (1 ng/mL) (data only reported in figures).
|
PFOA exposure reduced viability and of FRTL5 cells, and proliferation of FRTL5 and NHT cells. |
K2 Aim of the study was to evaluate the effect of the in vitro exposure to PFOA on thyroid cell proliferation and viability. Number of experiments and replicates not given. Conversion from ng/mL based on a molecular weight of 414 for CAS No. 335-67-1. Funded by Università degli Studi di Pavia. Authors declared no conflicts of interest.
|
|
PFOA CAS No. not given. Purity not given. Coperchini et al. (2021).
|
NHT cells. WST-1 assay: 2 x 104 cells/well. (96 well plate). No. of expts. and replicates not given. Annexin V‑FITC/PI assay: 1 x 104 cells/well. (24 well plate). No. of expts. and replicates not given. Cell proliferation assay: 500 cells/well (12 well plate)No. of expts. and replicates not given. Non-GL study. GLP not stated. |
WST-1 assay: 0, 2.41 x 10-2, 2.41 x 10-1, 2.41, 2.41 x 101 or 2.41 x 102. (originally reported as 0, 0.01, 0.1, 1, 10 or 100 ng/mL). 6H medium. 24, 48, 72, or 144 hr. Annexin V‑FITC/PI assay: 0 or 2.41 x 102. (originally reported as 100 ng/mL). 6H medium. 144 hr. Cell proliferation assay: 0, 2.41 x 10-2, 2.41 x 10-1, 2.41, 2.41 x 101 or 2.41 x 102. (originally reported as 0, 0.01, 0.1, 1, 10 or 100 ng/mL). 6H medium. 6 days. |
6H medium. NA. WST-1 assay. No effect on cytotoxicity. |
Cell viability. Cell death (apoptosis), late apoptotic, or necrotic cells. Cell proliferation. |
WST-1 assay: No effect on NHT cells (data only reported in figures). Annexin V‑FITC/PI assay: No effect on NHT cells (data only reported in figures). Cell proliferation assay: No effect on NHT cells (data only reported in figures).
|
PFOA exposure reduced viability and of FRTL5 cells, and proliferation of FRTL5 and NHT cells. |
K2 Aim of the study was to evaluate the in vitro effects of PFOA on primary cultures of NHT cells in terms of cell viability, proliferation rate, and ROS production, after both short and long time of exposure. Number of experiments and replicates not given. Conversion from ng/mL based on a molecular weight of 414 for CAS No. 335-67-1. Funded by Università degli Studi di Pavia. Authors declared no conflicts of interest.
|
|
PFOA CAS No. not given. Purity not given. Croce et al. (2019). |
WST-1 assay: FRTL-5 cells. 2 x 104 cells/well (96 well plate). 3 expts. No. of replicates not given. cAMP assay: No. cells not given (80% confluence). No. of replicates not given, 3 expts. Non-GL study. GLP not stated. |
0, 1 x 10-1, 1 x 10, 1 x 102, 1 x 103, 1 x 104 or 1 x 105 24 hr.
|
6H medium. 1 mU/LTSH (cAMP assay). WST-1 assay. No effect on cytotoxicity (data only reported in figures). |
Thyroid cell viability. TSH-stimulated cAMP production. |
No effect on inhibition of TSH-induced cAMP producton in FRTL-5 cells (data only reported in figures). |
cAMP production is not modulated by PFOA. The study excludes an interference with the TSH-dependent control of thyroid function as a mechanism by which PFOA would interfere with thyroid function. |
K2 Aim of the study was to investigate whether PFBS could affect thyroid cell viability and/or interfere with the functional effect of TSH by investigating TSH-induced cAMP production in FRTL-5 cells. Number of replicates not given. Purity not given. No details of funding given. Authors declare no conflict of interest.
|
|
PFOA CAS No. not given. Purity not given. De Toni et al. (2022).
|
FRTL-5 cells. Cell growth (MTT assay): 3-8 x 103 cells/well (96 well plate). 3 expts. in triplicate. cAMP assay: No. cells not given (80% confluence). (96 well plate). 3 expts. in triplicate. Iodide uptake assay: No. cells not given (60% confluence) (96 well plate). 3 expts. in triplicate. Non-GL study. GLP not stated. |
0, 2.41 x 10-1, 2.41, 2.41 x 101 or 2.41 x 102. (originally reported as 0, 0.1, 1, 10 or 100 ng/mL). Cell growth: 24h. cAMP assay: 72h. Iodide uptake assay: 24 hr. |
Coon′s modified Ham′s F12. Medium. 1 mU/LTSH (cAMP assay). NaSCN (Iodide uptake assay). MTT assay. No effect on cytotoxicity. |
Cell growth and membrane fluidity. Total RNA. TSH-stimulated cAMP production. Iodide uptake. |
↓ basal iodide uptake in cells in the absence of TSH stimulation at 2.41 x 10-1nM (0.1 ng/mL) and ≥ 24.1 nM (10 ng/mL) (data only reported in figures). ↑ increase in iodide uptake in cells following TSH stimulation from 2.41 x 10-1nM (0.1 ng/mL) (data only reported in figures). No effect on mean fluorescence intensity of MC540 staining (a proxy of membrane fluidity). ↓ intracellular cAMP levels from 2.41 x 10-1nM (0.1 ng/mL) (data only reported in figures). ↓ NIS and TPO gene expression from 2.41 x 10-1 nM (0.1 ng/mL) following TSH stimulation (data only reported in figures). |
Legacy and new generation PFAS can differentially influence TSH dependent signalling pathways through the direct interaction with TSH-R. Computer-Based Molecular Docking and Molecular Dynamics Analysis shows the possible interference the TSH/TSH-R interaction. Focusing on the amino acid region of TSH-R around ASP160, previously shown to highly involved in the activation by TSH, shows that the modelled binding of PFOA was associated with an increase of the backbone flexibility. |
K2 Aim of the study was to assess the potential disrupting effect of PFAS, on FRTL-5 cells via cell function, cell toxicity, membrane biophysical properties and computational modelling of the possible interaction with TSH-Receptor. Number of replicates not given, Purity not given. Conversion from ng/mL based on a molecular weight of 414 for CAS No. 335-67-1. Study funded by Solvay Specialty Polymers Italy S.p.A. The funder had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data, or approval of the manuscript; and decision to submit the manuscript for publication. |
|
PFOA CAS No. 335-67-1. 95%. Long et al. (2013). |
GH3 cells. 3 x 103 cells/well (96 well plate). 3 expts. in quadruplicate. Non-GL study. GLP not stated. |
1 - 1 x 105. 6 days. |
0.02% DMSO / 0.02% EtOH. 0.5 nM T3. LDH. Cytotoxic at >1 x 106 nM. |
Thyroid hormone-dependent cell growth (T-screen assay). |
Without T3 (agonistic response). ↓ cell proliferation. LOEC = 1 nM RPE at MOEC = -2.71% relative to T3. With T3 (competitive response). No effect on T3-induced cell proliferation. |
PFOA has the potential to inhibit the function of the TH system. Thus, PFOA might affect the endocrine homeostasis via interfering with nuclear receptor pathways including PPAR, ER, AR, TR and AhR. |
K2 Aim of the study was to assess in vitro the potential impacts of seven PFAS on AhR function. T-screen assay exposure duration 6 days. Study funded by the Danish Strategic Research Council and Aarhus University. |
|
PFOA CAS No. 335-67-1. 95%. Long et al. (2013). |
Hepa1.12cR cells. 6 × 104 cells/per well. 2 expts. in triplicate. Non-GL study GLP not stated. |
1 - 1 x 105 Duration not given. |
0.02% DMSO. 60 pM TCDD. LDH. Cytotoxic at >1 x 106 nM. |
Activation / inhibition of AhR (AhR transcriptional activation bioassay). |
Without TCDD (agonistic response). No observed effect. With TCDD (antagonistic response). No observed effect.
|
No effect on AhR. |
K1 No data on the number of cells plated. The AhR transcriptional activity was determined by AhR-luciferase reporter gene bioassay using the stably transfected mouse Hepa1.1 2cR cell. Study funded by the Danish Strategic Research Council and Aarhus University. |
|
PFOA CAS No. not given. Purity not given. Ren et al. (2016). |
Human WT TTR. 50 nM. Human mutant TTRmutK15G. 500 nM. 3 expts. in triplicate. Non-GL study. GLP not stated. |
Human WT and TTRmutK15G. 1 – 1 x 106 (estimated from figures. 5 minutes.
|
Competitive binding assay: NA. 50 nM F-T4. Cytotoxicity NA.
|
Binding potency to TTR. |
WT TTR. IC50 = 3.78 x 102 5 nM. RP = 0.083 relative to T4. TTRmutK15G. No observed effect.
|
Binding affinities of TTR to PFAS were much stronger than those of TBG to the same PFAS. PFAS might bind to TTR but not TBG when ingested and enter the blood stream. Displacement of T4 from TTR may be a concern for workers occupationally exposed to PFAS but not for the general population. PFOA could completely displace T4 from TTR in production workers. |
K1 Aim of the study was to investigate the binding affinities of PFAS with human TH transport proteins TTR and TBG. Of the 16 PFAS studied, PFOA had the second highest potency relative to T4, for WT TTR. Purity not given. Funded by the Chinese Academy of Sciences and the National Natural Science Foundation of China. Authors declared no conflicts of interest. |
|
PFOA CAS No. not given. Purity not given. Ren et al. (2016). |
Human WT TBG. 50 nM.
Human mutant TBGmutR378G. 1000 nM. Human mutant. TBGmutR381G. 1000 nM. 3 expts in triplicate. Non-GL study. GLP not stated. |
Human WT TBG, TBGmutR378G and TBGmutR381G. 1 – 1 x 106 (estimated from figures). 5 minutes.
|
NA. 50 nM F-T4. Cytotoxicity NA.
|
Binding potency to TBG. |
WT TBG. No observed effect. TBGmutR378G. No observed effect. TBGmutR381G. No observed effect.
|
Binding affinities of TTR to PFAS were much stronger than those of TBG to the same PFAS. PFAS might bind to TTR but not TBG when ingested and enter the blood stream. |
K1 Aim of the study was to investigate the binding affinities of PFAS with human TH transport proteins TTR and TBG. Purity not given. Funded by the Chinese Academy of Sciences and the National Natural Science Foundation of China. Authors declared no conflicts of interest. |
|
PFOA CAS No. 335-67-1. 96%. Weiss et al. (2009). |
TTR. 30nM. No. of expts. and replicates not given. Non-GL study. GLP not stated. |
1 x 101 – 1 x 104. Overnight. |
NA. T4. Cytotoxicity NA. |
T4-TTR-binding. |
IC50 = 9.49 x 102 nM. RP = 0.064 relative to T4. |
Competitive binding of PFCs to TTR, as observed for human TTR in the present study with certain PFAS, may explain altered TH levels described for PFC-exposed rats and monkeys. |
K2 Aim of the study was to investigate if PFAS compete with T4 for binding to TTR. Number of experiments and replicates not given. Study funded by EU-supported program MODELKEY and the Marie Curie Research Training Network KEYBIOEFFECTS. |