1-(2,4-dimethylcyclohex-3-en-1-yl)propan-1-ol

Endpoint summary

Description of key information

The skin sensitisation potential of the test substance has been tested according to OECD TG 429: Local Lymph Node Assay" method. At 10, 25 and 50% the substance showed SI values of 1.35, 1.46 and 1.17 , respectively.

The skin sensitization potential of the testsubstance was evaluated in a Direct Peptide reactivity Assay, consistent with OECD TG 442C. The test article was determined to be a non-sensitizer, based on minimal peptide reactivity.

The skin sensitization potential of the test substance was evaluated in a KeratinoSens Assay, Consistent with )ECD TG 442D. The test article was predicted to be a non-sensitizer.

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records

Reference

Reference 1

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

The study was conducted between 04 November 2016 and 29 November 2016

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: The study is considered to be a reliability 1 as it has been conducted according to OECD Test Guideline 429 using the Skin Sensitisation: Local Lymph Node Assay method and in compliance with GLP.

Qualifier:

according to guideline

Guideline:

OECD Guideline 429 (Skin Sensitisation: Local Lymph Node Assay)

Version / remarks:

22 July 2010

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.42 (Skin Sensitisation: Local Lymph Node Assay)

Version / remarks:

EC No. 440/2008

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of study:

mouse local lymph node assay (LLNA)

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: Sponsor Batch No. PDJ378-75
- Expiration date of the lot/batch: 01 June 2018
- Purity test date: 11 July 2016
- Purity: 96%
- Appearance: White solid
- Storage condition of test material: room temperature in the dark

Species:

mouse

Strain:

CBA/Ca

Remarks:

CBA/CaOlaHsd

Sex:

female

Details on test animals and environmental conditions:

Female CBA/Ca (CBA/CaOlaHsd) strain mice were supplied by Envigo RMS B.V., Inc., Horst, The Netherlands. On receipt the animals were randomly allocated to cages. The animals were nulliparous and non pregnant. After an acclimatisation period of at least five days the animals were selected at random and given a number unique within the study by indelible ink marking on the tail and a number written on a cage card. At the start of the study the animals were in the weight range of 15 to 23 g, and were eight to twelve weeks old.

The animals were individually housed in suspended solid floor polypropylene cages furnished with softwood woodflakes. Free access to mains tap water and food (2014C Teklad Global Rodent diet supplied byEnvigo RMS (UK) Limited, Oxon, UK) was allowed throughout the study.
The temperature and relative humidity were controlled to remain within target ranges of xx toxx°C and xx toxx %, respectively. Any occasional deviations from these targets were considered not to have affected the purpose or integrity of the study. The rate of air exchange was approximately xxx changes per hour and the lighting was controlled by a time switch to give twelve hours continuous light and twelve hours darkness.

The animals were provided with environmental enrichment items which were considered not to contain any contaminant of a level that might have affected the purpose or integrity of the study.

Vehicle:

acetone/olive oil (4:1 v/v)

Concentration:

Preliminary Test:
Test item at a concentration of 50% w/w in acetone/olive oil 4:1

Main Test:
Test item at concentrations of 50%, 25% or 10% w/w in acetone/olive oil 4:1.

No. of animals per dose:

Preliminary test : one mouse

Main Test: 5 mice per concentration

Details on study design:

Dissiminated (delete when editing)

Preliminary Screening Test
Using available information regarding the irritancy potential of the test item, a preliminary screening test was performed using one mouse. The mouse was treated by daily application of 25 µl of the test item at a concentration of 50% w/w in acetone/olive oil 4:1, to the dorsal surface of each ear for three consecutive days (Days 1, 2, 3). The mouse was observed twice daily on Days 1, 2 and 3 and once daily on Days 4, 5 and 6. Local irritation was scored daily according to the erythema scores. Any clinical signs of toxicity, if present, were also recorded. The bodyweight was recorded on Day 1 (prior to dosing) and on Day 6.

The thickness of each ear was measured using a Mitutoyo 547 300S gauge (Mitutoyo Corporation), pre dose on Day 1, post dose on Day 3 and on Day 6. Any changes in the ear thickness were noted. Mean ear thickness changes were calculated between Days 1 to 3 and Days 1 to 6. A mean ear thickness increase of equal to or greater than 25 % was considered to indicate excessive irritation and limited biological relevance to the endpoint of sensitisation.

Main Test
Test Item Administration
Groups of five mice were treated with the undiluted test item or the test item at concentrations of 50 % or 25 % v/v in acetone/olive oil 4:1. The preliminary screening test suggested that the test item would not produce systemic toxicity or excessive local irritation at the highest suitable concentration. The mice were treated by daily application of 25 µl of the appropriate concentration of the test item to the dorsal surface of each ear for three consecutive days (Days 1, 2, 3). The test item formulation was administered using an automatic micropipette and spread over the dorsal surface of the ear using the tip of the pipette.
A further group of five mice received the vehicle alone in the same manner.

The positive control animals were similarly treated to the test animals except that 25 µl of the positive control item, α Hexylcinnamaldehyde, 97.3 %, at a concentration of 25 % v/v in acetone/olive oil 4:1 was applied to the dorsal surface of each ear.

3H-Methyl Thymidine Administration
Five days following the first topical application of the test item, vehicle control or positive control item (Day 6) all mice were injected via the tail vein with 250 µl of phosphate buffered saline (PBS) containing 3H methyl thymidine (3HTdR:80µCi/ml, specific activity 2.0 Ci/mmol, ARC UK Ltd) giving a total of 20 µCi to each mouse.

Observations
Clinical Observations: All animals were observed twice daily on Days 1, 2 and 3 and on a daily basis on Days 4, 5 and 6. Any signs of toxicity or signs of ill health during the test were recorded.

Bodyweights: The bodyweight of each mouse was recorded on Day 1 (prior to dosing) and Day 6 (prior to termination).

Terminal Procedures
Termination: Five hours following the administration of 3HTdR all mice were killed by carbon dioxide asphyxiation followed by cervical separation. For each individual animal of each group the draining auricular lymph nodes were excised and processed. For each individual animal 1 ml of PBS was added to the lymph nodes.

Preparation of Single Cell Suspension: A single cell suspension of the lymph node cells for each individual animal was prepared by gentle mechanical disaggregation through a 200 mesh stainless steel gauze. The lymph node cells were rinsed through the gauze with 4 ml of PBS into a petri dish labelled with the project number and dose concentration. The lymph node cells suspension was transferred to a centrifuge tube. The petri dish was washed with an additional 5 ml of PBS to remove all remaining lymph node cells and these were added to the centrifuge tube. The lymph node cells were pelleted at 1400 rpm (approximately 190 g) for ten minutes. The pellet was resuspended in 10 ml of PBS and re-pelleted. To precipitate out the radioactive material, the pellet was resuspended in 3 ml of 5% Trichloroacetic acid (TCA).

Determination of 3HTdR Incorporation: After approximately eighteen hours incubation at approximately 4°C, the precipitates were recovered by centrifugation at 2100 rpm (approximately 450 g) for ten minutes, resuspended in 1 ml of TCA and transferred to 10 ml of scintillation fluid. 3HTdR incorporation was measured by beta scintillation counting. The "Poly QTM" vials containing the samples and scintillation fluid were placed in the sample changer of the scintillator and left for approximately twenty minutes. The purpose of this period of time in darkness was to reduce the risk of luminescence, which has been shown to affect the reliability of the results. After approximately twenty minutes, the vials were shaken vigorously. The number of radioactive disintegrations per minute was then measured using the Beckman LS6500 scintillation system (Beckman Instruments Inc, Fullerton, CA, USA).
3
Data Evaluation
The proliferation response of lymph node cells was expressed as the number of radioactive disintegrations per minute per animal and as the ratio of 3HTdR incorporation into lymph node cells of test nodes relative to that recorded for the control nodes (Stimulation Index).
The test item will be regarded as a sensitizer if at least one concentration of the test item results in a threefold or greater increase in 3HTdR incorporation compared to control values. Any test item failing to produce a threefold or greater increase in 3HTdR incorporation will be classified as a "non sensitizer".
The results were also interpreted according to Regulation (EC) No. 1272/2008, relating to the Classification, Labelling and Packaging of Substances and Mixtures and the Globally Harmonized Classification System.

Positive control substance(s):

hexyl cinnamic aldehyde (CAS No 101-86-0)

Statistics:

Data was processed to give group mean values for disintegrations per minute and standard deviations where appropriate. Individual and group mean disintegrations per minute values were assessed for dose response relationships. Data was first assessed for suitability by analysis of normality and homogeneity of variance. If the assumptions that the data are both normally distributed and has homogeneity of variances, then parametric one way analysis of variance (ANOVA) and Dunnett’s multiple comparison procedure were used to determine statistical significance. If the assumptions were not met, non parametric Kruskal Wallis Rank Sum and Mann Whitney U test procedures were used.
Probability values (p) are presented as follows:
P<0.001 ***
P<0.01 **
P<0.05 *
P>0.05 (not significant)

Positive control results:

The positive control item, α-Hexylcinnamaldehyde, 97.3%, gave a Stimulation Index of greater than 3 when tested at a concentration of 25 % v/v in acetone/olive oil 4:1.

Key result

Parameter:

SI

Remarks on result:

other: The following SI values were derived at 10, 25 and 50%:1.35, 1.46 and 1.17, respectively.

Preliminary screening test:

No signs of systemic toxicity or excessive irritation indicated by an equal to or greater than 25% increase in mean ear thickness were noted.  Based on this information the dose levels selected for the main test were 50%, 25% and 10% w/w in acetone/olive oil 4:1

Main Test

Estimation of the Proliferative Response of Lymph Node Cells

The radioactive disintegrations per minute per lymph node and the stimulation index are given in Appendix 4.

The Stimulation Index expressed as the mean radioactive incorporation for each treatment group divided by the mean radioactive incorporation of the vehicle control group are as follows:

Treatment Group	Concnetration	Simulation Index	Result
Test Item	10% w/w in acetone/olive oil 4:1	1.35	Negative
	25% w/w in acetone/olive oil 4:1	1.46	Negative
	50% w/w in acetone/olive oil 4:1	1.17	Negative
Positive Control Item	25% w/w in acetone/olive oil 4:1	5.68	Positive

Clinical Observations and Mortality Data

There were no deaths.  No signs of systemic toxicity were noted in the test or control animals during the test.

Body Weight

Body weight change of the test animals between Day 1 and Day 6 was comparable to that observed in the corresponding control group animals over the same period.

Interpretation of results:

other: considered to be a non-sensitizer under the conditions of the test

Conclusions:

The test item was considered not to be a sensitiser under the conditions of the test .

Executive summary:

The skin sensitisation potential of the test substance has been tested according to OECD TG 429: Local Lymph Node Assay" method. At 10, 25 and 50% the substance showed SI values of 1.35, 1.46 and 1.17 , respectively.

Reference 2

Endpoint:

skin sensitisation: in chemico

Type of information:

experimental study

Adequacy of study:

key study

Study period:

December 18, 2014 - June 25, 2015

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 442C (In Chemico Skin Sensitisation: Direct Peptide Reactivity Assay (DPRA))

Deviations:

not specified

Principles of method if other than guideline:

The DPRA assy utilizes an in chemico approach to measure the depletion of the cysteine and lysine containing peptides using HPLC. The peptides are custom materials containing phenylalanine to aid in detection of either cystein or lysine as the reactive center (Gerberick, et al, 2014). The concentrations of each peptide within each sample or control is then measured by HPLC and UV detection at 220 nm.

GLP compliance:

no

Remarks:

The GLP gap is related to the lack of involvement of the laboratory's Quality Assurance unit in the process of protocol review, review of the GLP draft report, etc. However, the study was otherwise conducted in the full spirit of GLP.

Type of study:

direct peptide reactivity assay (DPRA)

Details on the study design:

Test Article Preparation: The test articles tested in this assay were prepared at 100 mM concentrations in appropriate solvents based on the molecular weights and purities of the test articles supplied by the sponsor. On the day of the assay, the test articles were weighed into prelabeled glass vials and stored at room temperature. The test articles were not dissolved in the solvents until immediately before testing.

Test Article Solubility Test: The test articles were tested to determine appropriate solvents that completely dissolved each test article. The test articles were dissolved by vortexing in the appropriate solvent for approximately 1 minute. The solvent used for all of the test articles in this assay was acetonitrile. Solvent controls for the solvent used were run concurrently with the test articles.

Preparation of the Peptides: Custom synthetic peptides of lysine and cysteine (containing phenylalanine to aid in detection) were used in this assay. The purity of each peptide was 90-95%. Peptide samples were newly prepared for each sample set, and a single preparation of the peptide was used throughout the sample set. The cysteine peptide was prepared by weighing an appropriate amount of the peptide to achieve a 0.667 mM concentration in pH 7.5 phosphate buffer. The lysine peptide was prepared by weighing an appropriate amount of the peptide to achieve a 0.667 mM concentration in pH 10.2 ammonium acetate buffer. The peptide solutions were gently mixed on the shaker.

Peptide Standards: A set of serially diluted standards were prepared for each peptide. These standards were prepared by diluting the peptide solutions in dilution buffer (acetonitrile using either phosphate or ammonium acetate buffer). Six standards were prepared at concentrations of 0.534- 0.0167 mM. A seventh standard was prepared containing only dilution buffer. Approximately 1 mL of each standard was pipetted into the appropriate prelabeled autosampler vials.

Controls: The positive control used in this assay was cinnamic aldehyde prepared at a concentration of 100 mM. The positive control was reacted with the peptides in the same fashion as the test articles. Reference Controls were used for each solvent used in the assay. There were three sets of triplicate Reference Controls of acetonitrile run at different points throughout the assay. These controls consist of the solvent reacted with the peptide in the absence of test article. Co-elution controls were also prepared for each test article. The co-elution controls consisted of each test article without the peptide. The purpose of
the co-elution controls was to determine if the test article elution from the HPLC column overlapped with the peptide elution.

Sample Preparation: Immediately prior to testing, the test articles were diluted in the appropriate solvent to yield 100 mM test article samples. The test articles were mixed as determined during the solubility test. The final dosing solutions were prepared for the test articles, positive control, and Reference Controls in the prelabeled autosampler vials. Table 1 shows the composition of the final samples for HPLC analysis. Triplicate samples were prepared for the test articles and the controls. Single samples were prepared for the co-elution controls.

HPLC Set-up and Operation: The separations module used in this assay was a Waters 2690/5 HPLC system. This system consists of a solvent management system for the mobile phases and a sample management system for the test articles and controls. The HPLC system is coupled to a photodiode array detector set at 220 nm. The dimensions of the column used are 2.1 mm x 00 mm x 3.5 micron. The column was primed for at least two hours before the start of the assay. To prime the column, equal parts of mobile phase A (0.1% trifluoroacetic acid in HPLC grade water) and mobile phase B (0.08% trifluoroacetic acid in HPLC grade acetonitrile) were passed through the column. Once the column was equilibrated and the samples were prepared, the labeled autosampler vials were placed into the designated locations of the separations module carousels. The samples were incubated in the dark at room temperature for 24± 2 hours.

A gradient elution was used in this assay. The mobile phase changed from 10-25% acetonitrile over a 10 minute period to allow for optimal separation and to gradually elute most of the sample from the column. This was followed by a rapid increase to 90% acetonitrile to remove anything remaining on the column. The column was allowed to equilibrate back to initial specs for 7 minutes between injections.

The Empower PDA software was used to convert the absorbance data from the UV detector into chromatograms of intensity versus retention time for each sample and control. At the end of the run, the peak corresponding to either the cysteine peptide or the lysine peptide was integrated on each chromatogram in order for the software to calculate the area under the peptide peak. Cysteine and lysine elute from the column at known times, so it was possible to determinewhich peaks in the chromatograms represented the peptides and use the areas under those peaks for the subsequent calculations.

Positive control results:

Positive control was cinnamic aldehyde. For each definitive assay, the positive control acceptance range for cysteine depletion is 60.8 - 100.0, and the positive control acceptance range for lysine depletion is 40.2 - 69.4. The positive control must also meet the following standard deviation criteria: cystein depletion must be < 14.9%, and lysine depletion must be < 11.6%.

For the assay in which FRET 11-0571 was evaluated, the positive control depeletd cysteine peptides by 81.8%, and depeletd lysine peptides by 63.0%, thereby meeting the acceptance criteria for the validity of the assay rersults.

Key result

Run / experiment:

other: Assay results from December 18, 2014

Parameter:

other: Cysteine depletion

Value:

0.064

Vehicle controls validity:

not specified

Negative controls validity:

not specified

Positive controls validity:

valid

Remarks on result:

no indication of skin sensitisation

Remarks:

Minimal reactivity

Key result

Run / experiment:

other: Assay results from December 18, 2014

Parameter:

other: Lysine depletion

Value:

0.051

Vehicle controls validity:

not specified

Negative controls validity:

not specified

Positive controls validity:

valid

Remarks on result:

no indication of skin sensitisation

Remarks:

Minimal reactivity

Key result

Run / experiment:

other: Assay results from December 18, 2014

Parameter:

other: Combine Cysteine + Lysine depletion

Value:

0.057

Vehicle controls validity:

not specified

Negative controls validity:

not specified

Positive controls validity:

valid

Remarks on result:

no indication of skin sensitisation

Remarks:

Minimal reactivity

Interpretation of results:

study cannot be used for classification

Conclusions:

The test article FRET 11-0571 was determined to be a non-sensitizer, based on minimal peptide reactivity.

Executive summary:

The test article FRET 11 -0571 was evaluated for skin sensitization potential using the Direct Peptide Reactivity Assay, which is consistent with OECD Test Guideline 442C. The test article was reacted with synthetic peptides of cysteine and lysine and the depletion of the peptide was evaluated using HPLC with UV detection. The percent depletion of the peptides incubated with the test article was calculated by comparing peak area of the test article incubated peptides to the mean peak area of the solvent control incubated peptides. This percent depletion was then correlated to a reactivity class and the sensitizing potential of the test article (negative or positive for skin sensitization potential). The test article FRET 11-0571 was determined to be a non-sensitizer, based on minimal peptide reactivity.

Reference 3

Endpoint:

skin sensitisation: in vitro

Type of information:

experimental study

Adequacy of study:

key study

Study period:

December 16, 2014 - January 23, 2015

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 442D (In Vitro Skin Sensitisation: ARE-Nrf2 Luciferase Test Method)

Deviations:

not specified

Principles of method if other than guideline:

The Induction of Antioxidant-Response-Element Dependent Gene Activity in the Keratinocyte ARE- Reporter Cell Line KeratinoSens skin sensitization assay is a
cell-based in vitro test to screen for the skin sensitization potential of chemicals. The KeratinoSens cells (Givaudan, Switzerland) were propagated as a reporter cell line. The KeratinoSens cells are transfected HaCaT keratinocytes that include a 56-base-pair insertion containing the ARE sequence from the AKR1C2 gene, a SV40 promoter, the luciferase gene in the vector pGL4 from Promega, and a stable insertion allowing for cells to be selected in the presence of Geneticin (G418). The signalling pathway with the repressor protein Keap1 and the transcription factor Nrf2, which binds to the antioxidant / electrophile response element
(ARE / EpRE), was shown to be a valuable cellular endpoint to detect skin sensitizers in vitro. The induction of luciferase directly indicates the activation of ARE-
dependent genes. Additionally, the cytotoxicity of a test article was assessed using cell MTT (3-[4,5 - dimethylthiazol-2-yl] - 2,5 - diphenyltetrazolium bromide).
Cytotoxicity was determined by measuring the relative conversion of MTT in test article-treated cultures compared to the solvent control.

GLP compliance:

no

Remarks:

The GLP gap is related to the lack of involvement of the laboratory's Quality Assurance unit in the process of protocol review, review of the GLP draft report, etc.However, the study was otherwise conducted in the full spirit of GLP.

Type of study:

activation of keratinocytes

Details on the study design:

The experimental design of this study consisted of three definitive assays to determine the maximal induction (Imax), the concentration for maximal gene induction(CImax), the EC1.5 value (concentration for a statistically significant induction of 50% above solvent controls), and a mean IC50 (concentration leading to 50%
viability as compared to solvent controls) for the test articles. For each definitive assay, the KeratinoSens cells were cultured in quadruplicate plates for 24
hours, treated with the test articles for 48 hours, and assessed for luciferase induction (3 plates) and cytotoxicity (1 plate). The procedures that were performedin this assay were a modification of the procedures previously described by Natsch, et al. (2008) and were performed similar to those procedures performed by the Institute for In Vitro Sciences, Inc. in the KeratinoSens ring-study.

Positive control substance(s):

other: Cinnamic Aldehyde (CAS 104-55-2)

Positive control results:

The positive control, Cinnamic Aldehyde, was tested at 5 concentrations ranging from 64 to 4 μM. The KeratinoSens assay was accepted when the positive control caused an in vitro score that fell within two standard deviations of the historical mean. The EC1.5 value of the positive control was 8.92 um, the mean IC50 was > 64 um, and cinnamic aldehyde was determined to be a sensitizer, and therefore the validityof the assay was confirmed.

Key result

Run / experiment:

other: Test Article code 14AQ08

Parameter:

other: EC1.5

Value:

2 000

Vehicle controls validity:

not specified

Negative controls validity:

not specified

Positive controls validity:

valid

Key result

Run / experiment:

other: Test article code 14AQ08

Parameter:

other: Mean IC50

Value:

1 089.96

Vehicle controls validity:

not specified

Negative controls validity:

not specified

Positive controls validity:

valid

Key result

Run / experiment:

other: Test article code 14AQ08

Parameter:

other: Maximal induction (Imax)

Value:

1.09

Vehicle controls validity:

not specified

Negative controls validity:

not specified

Positive controls validity:

not applicable

Key result

Run / experiment:

other: Test article code 14AQ08

Parameter:

other: Concentration for maximal gene induction (CImax)

Value:

7.81

Vehicle controls validity:

not specified

Negative controls validity:

not specified

Positive controls validity:

not applicable

Interpretation of results:

study cannot be used for classification

Conclusions:

According to the prediction model, the test article FRET 11-0571 was predicted to be a non-sensitizer.

Executive summary:

The Induction of Antioxidant-Response-Element Dependent Gene Activity in the Keratinocyte ARE- Reporter Cell Line KeratinoSens skin sensitization assay is a cell-based in vitro test to screen for the skin sensitization potential of chemicals, and is consistent with OECD Test Guideline 442D. The KeratinoSens cells (Givaudan, Switzerland) were propagated as a reporter cell line. The KeratinoSens cells are transfected HaCaT keratinocytes that include a 56-base-pair insertion containing the ARE sequence from the AKR1C2 gene, a SV40 promoter, the luciferase gene in the vector pGL4 from Promega, and a stable insertion allowing for cells to be selected in the presence of Geneticin (G418). The signalling pathway with the repressor protein Keap1 and the transcription factor Nrf2, which binds to the antioxidant / electrophile response element (ARE / EpRE), was shown to be a valuable cellular endpoint to detect skin sensitizers in vitro1,2. The induction of luciferase directly indicates the activation of ARE-dependent genes. Additionally, the cytotoxicity of a test article was assessed using cell MTT (3-[4,5 - dimethylthiazol-2-yl] - 2,5 - diphenyltetrazolium bromide). Cytotoxicity was determined by measuring the relative conversion of MTT in test article-treated cultures compared to the solvent control. According to the prediction model, the test article FRET 11-0571 was predicted to be a non-sensitizer.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Respiratory sensitisation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information:

Migrated from Short description of key information:
Respiratory sensitisation can be assessed using human data such as indicated in R7.3.5.2 of the ECHA guidance (2015) that indicate respiratory reactions e. g. from consumer experience or occupational exposure. In case no such data are available the respiratory sensitisation can be assessed using the integrated evaluation strategy for respiratory sensitisation data in the ECHA guidance (R7A, Fig. 7.3-2, 2015), which says that if the substance is a non skin sensitiser, than it is unlikely to be a respiratory sensitiser.

Justification for classification or non-classification

In view of the negative results in the LLNA study the substance does not need to be classifief for skin sensitisation.

The substance FRET 11-0571 is negative in the LLNA skin sensitisation study and therefore classification of this substance for skin and respiratory sensitisation is not warranted according to EU Classification, Labelling and Packaging of Substances and Mixtures (CLP) Regulation (EC) No. 1272/2008.

In addition, the negative results of the in chemico assay (DPRA) and in vitro assay (KeratinoSens) support the conclusion that the test substance FRET 11 -0571 is not a sensitizer, and therefore does not need to be classified for this endpoint.