Reaction products of Dihydro-3-(tetrapropenyl)furan-2,5 dione with propane-1,2,diol

Endpoint summary

Description of key information

Under the conditions of the study, the test material was considered to be a non-sensitiser.

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records

Reference

Reference 1

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

25 January 2016 to 16 March 2016

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.6 (Skin Sensitisation)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.2600 (Skin Sensitisation)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of study:

Buehler test

Justification for non-LLNA method:

The LLNA is the study of choice for skin sensitisation. As detailed in the OECD 429 guideline, despite the advantages of the LLNA, it should be recognised that there are certain limitations that may necessitate the use of TG 406. Chemical groups such as metal salts, organometal, unsaturated compounds and surfactants have been known to be linked to false positives. The Substance is considered to be amphiphilic in nature and therefore would likely have surfactant characteristics, which are known to be falsely positive in the LLNA. Therefore a Guinea Pig Study, OECD 406, was selected to decrease the uncertainty of possible falsely positive effects.

Specific details on test material used for the study:

TREATMENT OF TEST MATERIAL PRIOR TO TESTING
- Treatment of test material prior to testing: For the purpose of the study, the test item was prepared immediately prior to dosing in liquid paraffin for the topical applications (pretests). This vehicle was chosen as it produced the most suitable formulation at the required concentration. Indeed, the preparation of the test item at 50 % in liquid paraffin (w/w) was a yellow solution.

Species:

guinea pig

Strain:

Dunkin-Hartley

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Age at study initiation: 3, 4, 5 or 6 weeks old at the beginning of the main test.
- Weight at study initiation: animal weight ranged between 262 g to 414 g
- Housing: The animals were housed in groups of maximum 3 in polycarbonate cages. The flooring of the cages was covered with dust-free wood shavings and the top fitted a stainless steel lid containing a feeding device and drinking device of 500 mL.
- Diet: Ad libitum
- Water: Ad libitum
- Acclimation period: Minimum acclimatization period of 5 days, under housing and diet conditions identical to those of the test.


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 °C ± 3 °C
- Humidity (%): 30 % to 70 %
- Air changes (per hr): At least 10 cycles per hour.
- Photoperiod (hrs dark / hrs light): Circadian cycle (12 hrs light/ 12 hrs darkness).

Route:

epicutaneous, occlusive

Vehicle:

paraffin oil

Remarks:

Liquid paraffin

Concentration / amount:

0.5 mL of the test item diluted at 10 % in liquid paraffin 10 % in liquid paraffin.

Day(s)/duration:

3 topical applications at 10 % in liquid paraffin under occlusive dressing for 6 hours

Adequacy of induction:

not specified

No.:

#1

Route:

epicutaneous, occlusive

Vehicle:

paraffin oil

Remarks:

Liquid paraffin

Concentration / amount:

0.5 mL of the test item diluted at 10 % in liquid paraffin

Day(s)/duration:

6 hours

Adequacy of challenge:

highest non-irritant concentration

No. of animals per dose:

GROUP 1 (negative control): 10 female guinea pigs
GROUP 2 (treated): 20 female guinea pigs

Details on study design:

RANGE FINDING TESTS
This test was carried out with a reduced number of animals, for the purpose of determining the maximal non-irritating test item concentration to be used for the challenge phase. Furthermore, this test evaluates the irritant potential of the test item, and defines, if possible, a mild to moderate irritant concentration to be used for the topical induction phase.
Three guinea pigs were treated with the test item placed onto the selected treatment sites and covered with an occlusive dressing (25 mm x 50 mm non-woven swab of 4-layer patch from MEDISTOCK held in contact with the skin by means of 50 mm wide hypoallergenic micropore™ adhesive tape from 3M and Blenderm™ from 3M) for a period of 6 hours at 4 different concentrations: 100 %, and diluted at 75 %, 50 % and 25 % in liquid paraffin. Washing of the skin after removal of the dressing was done with liquid paraffin.
The animals treated at the concentrations of 100 %, and diluted at 75 %, 50 % and 25 % received 0.5 mL of the corresponding preparation.
A macroscopic evaluation of the cutaneous reactions was conducted 24 and 48 hours after removal of the occlusive dressings. The skin reaction was observed and recorded according to the grades described hereafter.
Due to the results observed, three other guinea pigs were treated with the test item placed onto the selected treatment sites and covered with an occlusive dressing (25 mm x 50 mm non-woven swab of 4-layer patch from MEDISTOCK held in contact with the skin by means of 50 mm wide hypoallergenic micropore™ adhesive tape from 3M and Blenderm™ from 3M) for a period of 6 hours at 4 different concentrations: Diluted at 10 %, 5 %, 2 % and 1 % in liquid paraffin. Washing of the skin after removal of the dressing was done with liquid paraffin.
The animals treated at the diluted concentrations of 10 %, 5 %, 2 % and 1 % received 0.5 mL of the corresponding preparation.
A macroscopic evaluation of the cutaneous reactions was conducted 24 and 48 hours after removal of the occlusive dressings. The skin reaction was observed and recorded according to the grades described hereafter.
To confirm the results observed, two other guinea pigs were treated with the test item placed onto the selected treatment sites and covered with an occlusive dressing (25 mm x 50 mm non-woven swab of 4-layer patch from MEDISTOCK held in contact with the skin by means of 50 mm wide
hypoallergenic micropore™ adhesive tape from 3M and Blenderm™ from 3M) for a period of 6 hours at 4 different concentrations: Diluted at 25 %, 10 %, 5 % and 2 % in liquid paraffin. Washing of the skin after removal of the dressing was done with liquid paraffin.
The animals treated at the diluted concentrations of 25 %, 10 %, 5 % and 2 % received 0.5 mL of the corresponding preparation.
A macroscopic evaluation of the cutaneous reactions was conducted 24 and 48 hours after removal of the occlusive dressings. The skin reaction was observed and recorded according to the grades described hereafter.

MAIN STUDY
A. INDUCTION EXPOSURE
After shearing of the scapular zone, the 3 local applications were performed on D0, D6 and D13 for 6 hours under occlusive dressing (25 mm x 50 mm non-woven swab of 4-layer patch from MEDISTOCK held in contact with the skin by means of 50 mm wide hypoallergenic micropore™ adhesive tape from 3M and Blenderm™ from 3M).
The animals of the control group received 0.5 mL of liquid paraffin and the animals of the treated group received 0.5 mL of the test item diluted at 10 % in liquid paraffin. Washing of the skin after removal of the dressing was done with liquid paraffin.
The animals of both groups were left untreated for 13 days.

B. CHALLENGE EXPOSURE
The experimental procedure of this phase was identical for both groups Group 1 (Control) and Group 2 (Treated) according to this approach: On the previously shorn dorso-lumbar zone, an application on either side of the spine, under occlusive dressing (25 mm x 50 mm non-woven swab of 4-layer patch from MEDISTOCK held in contact with the skin by means of 50 mm wide hypoallergenic micropore™ adhesive tape from 3M and Blenderm™ from 3M), was performed for 6 hours:
- 1 area containing 0.5 mL of the test item diluted at 10 % (MNIC = maximal non-1mtant concentration) on the left flank, and
- 1 area containing 0.5 mL of liquid paraffin on the right flank. Washing of the skin after removal of the dressing was done with liquid paraffin.

OTHER: PREPARATION OF ANIMALS
The animals were carefully shorn before each test item application:
- On the inter-scapular zone for the induction phase,
- On the dorso-lumbar zone for the challenge phase and the re-challenge phase.
At least 3 hours before the first reading (challenge phase and re-challenge phase) they were shorn a second time in this dorso-lumbar zone.
The animals were weighed at the beginning, before the second induction, after the reading at 48 hours and at the end of the study.

OTHER: MACROSCOPIC EXAMINATION AND EVALUATION OF CUTANEOUS REACTIONS
A macroscopic evaluation of the cutaneous reactions (erythema and oedema) was conducted and all the local or systemic reactions were recorded for animals of Group 1 (Control) and Group 2 (Treated):
• Approximately 24 hours after removal of the occlusive dressing, the cutaneous reactions were observed and graded according to the scale given below.
• Approximately 24 hours later (i.e. 48 hours after removal of the occlusive dressing), a second observation was made.

Challenge controls:

The animals of the control groups were subject to the same experimental procedure as the treatment groups.

Positive control substance(s):

no

Remarks:

The results of the last three positive control groups treated with the reference substance α-hexylcinnamaldehyde carried out to demonstrate method sensibility were appended to the report.

Positive control results:

The results of the positive control show that the reference substance α-Hexylcinnamaldehyde caused skin sensitisation and therefore confirms the validity of the test.

Key result

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

10 % test material in liquid paraffin

No. with + reactions:

0

Total no. in group:

20

Clinical observations:

No abnormal clinical signs related to the administration of the test item were observed.

Remarks on result:

no indication of skin sensitisation

Key result

Reading:

2nd reading

Hours after challenge:

48

Group:

test chemical

Dose level:

10 % test material in liquid paraffin

No. with + reactions:

0

Total no. in group:

20

Clinical observations:

No abnormal clinical signs related to the administration of the test item were observed.

Remarks on result:

no indication of skin sensitisation

Reading:

1st reading

Hours after challenge:

24

Group:

negative control

Dose level:

10 % test material in liquid paraffin

No. with + reactions:

0

Total no. in group:

10

Remarks on result:

no indication of skin sensitisation

Reading:

2nd reading

Hours after challenge:

48

Group:

negative control

Dose level:

10 % test material in liquid paraffin

No. with + reactions:

0

Total no. in group:

10

Remarks on result:

no indication of skin sensitisation

Reading:

1st reading

Hours after challenge:

24

Group:

positive control

Dose level:

50 %

No. with + reactions:

8

Total no. in group:

20

Remarks on result:

positive indication of skin sensitisation

Reading:

2nd reading

Hours after challenge:

48

Group:

positive control

Dose level:

50 %

No. with + reactions:

4

Total no. in group:

20

Remarks on result:

positive indication of skin sensitisation

Preliminary Study

- MNIC determination: At the tested concentrations of 100 %, 75 % and 50 %, 24 and 48 hours after removal of the patches, intense erythema was noted in all animals (3/3).

At the tested concentration of 25 %, 24 hours after removal of the patches, intense erythema was noted in all animals (3/3). 48 hours after removal of the patches, moderate erythema was noted in one animal (1/3) and intense erythema in two animals (2/3).

24 and 48 hours after removal of the patches, no cutaneous reaction was noted at the tested concentrations of 10 %, 5 %, 2 % and 1 %.

24 and 48 hours after removal of the patches, no cutaneous reaction was noted at the tested concentrations of 25 %, 10 %, 5 % and 2 %.

In view of these results, and considering that the concentration of 25 % caused skin reactions in 3 out of 5 animals, the concentration selected was 10 % for the 3 inductions of the main study and the challenge phase.

Main Study

- Induction Phase: After the first induction in the treated group, moderate erythema was noted in one animal (1/20), discrete erythema was noted in three animals (3/20) and no cutaneous reaction was noted in the other animals (16/20).

After the second induction in the treated group, moderate erythema was noted in four animals (4/20) and discrete erythema was noted in sixteen animals (16/20).

After the third induction in the treated group, moderate erythema was noted in six animals (6/20), discrete erythema was noted in ten animals (10/20) and no cutaneous reaction was noted in the other animals (4/20).

No cutaneous reaction was recorded during the induction phase in the control group.

- Challenge Phase: In the treated group (treatment dose of 10 %), no macroscopic cutaneous reactions attributable to allergy were observed during the examination following the removal of the occlusive dressing. In the control group (associated with the treatment dose of 10 %), no cutaneous intolerance reactions were observed during the examination following the removal of the occlusive dressing. No cutaneous reaction was recorded in animals from the treated and control groups after the challenge phase on the treated area with liquid paraffin.

Weight evolution

No abnormalities and no differences in the body weight between the control and the treated group were observed.

Mortality

No mortality occurred during the main test.

Clinical signs

No abnormal clinical signs related to the administration of the test item were observed.

Interpretation of results:

GHS criteria not met

Conclusions:

Under the conditions of the study, the test material was considered to be a non-sensitiser.

Executive summary:

The potential of the test material to act as a sensitiser was investigated in a GLP study in accordance with the standardised guidelines OECD 406, EU Method B.6 and US EOA OPPTS 870.2600.

The induction phase (3 topical applications at 10 % in liquid paraffin under occlusive dressing for 6 hours) was conducted with the test material to 20 Guinea pigs and a 13-day rest phase. The challenge phase conducted under occlusive dressing for 6 hours, consisted of a single topical application of the test item diluted at 10 % in liquid paraffin and of a negative control (liquid paraffin).

The concentration selected for the induction phase and the challenge was based on the result of three pre-tests in which the concentration of 25 % caused skin reactions in 3 out of 5 animals, the concentration selected was 10 % for the 3 inductions of the main study and the challenge phase.

Readings were performed 24 and 48 hours after removal of the patches.

In the treated group (treatment dose of 10 %), no macroscopic cutaneous reactions attributable to allergy were observed during the examination following the removal of the occlusive dressing. In the control group (associated with the treatment dose of 10 %), no cutaneous intolerance reactions were observed during the examination following the removal of the occlusive dressing. No cutaneous reaction was recorded in animals from the treated and control groups after the challenge phase on the treated area with liquid paraffin.

Under the conditions of the study, the test material was considered to be a non-sensitiser.

Reference 2

Endpoint:

skin sensitisation: in vitro

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

other:

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Additional information:

The potential of the test material to act as a sensitiser was investigated in a GLP study in accordance with the standardised guidelines OECD 406, EU Method B.6 and US EOA OPPTS 870.2600. The study was assigned a reliability score of 1 in accordance with the criteria for assessing data quality set forth by Klimisch et al. (1997).

The induction phase (3 topical applications at 10 % in liquid paraffin under occlusive dressing for 6 hours) was conducted with the test material to 20 Guinea pigs and a 13-day rest phase. The challenge phase conducted under occlusive dressing for 6 hours, consisted of a single topical application of the test item diluted at 10 % in liquid paraffin and of a negative control (liquid paraffin).

The concentration selected for the induction phase and the challenge was based on the result of three pre-tests in which the concentration of 25 % caused skin reactions in 3 out of 5 animals, the concentration selected was 10 % for the 3 inductions of the main study and the challenge phase.

Readings were performed 24 and 48 hours after removal of the patches.

In the treated group (treatment dose of 10 %), no macroscopic cutaneous reactions attributable to allergy were observed during the examination following the removal of the occlusive dressing. In the control group (associated with the treatment dose of 10 %), no cutaneous intolerance reactions were observed during the examination following the removal of the occlusive dressing. No cutaneous reaction was recorded in animals from the treated and control groups after the challenge phase on the treated area with liquid paraffin.

Under the conditions of the study, the test material was considered to be a non-sensitiser.

Respiratory sensitisation

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

In accordance with the criteria for classification as defined in Annex I, Regulation (EC) No 1272/2008, the substance does not require classification with respect to skin sensitization.