Registration Dossier

Administrative data

Description of key information

Skin sensitisation: non-sensitiser (in vivo, in silico).

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records

Referenceopen allclose all

Endpoint:
skin sensitisation: in vivo (non-LLNA)
Type of information:
read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
key study
Justification for type of information:
For details on endpoint specific justification please refer to the read-across report, endpoint specific justification.
Reason / purpose:
assessment report
Reason / purpose:
read-across source
Key result
Reading:
1st reading
Hours after challenge:
24
Group:
test group
Dose level:
25% test substance preparation
No. with + reactions:
0
Total no. in group:
10
Clinical observations:
not reported
Remarks on result:
no indication of skin sensitisation
Remarks:
Effect conc. are identical for the submission substance, because target and source substance have the same MW.
Key result
Reading:
2nd reading
Hours after challenge:
48
Group:
test group
Dose level:
25% test substance preparation
No. with + reactions:
0
Total no. in group:
10
Clinical observations:
not reported
Remarks on result:
no indication of skin sensitisation
Remarks:
Effect conc. are identical for the submission substance, because target and source substance have the same MW.
Reading:
1st reading
Hours after challenge:
24
Group:
negative control
Dose level:
Freund's adjuvant / 90% aqueous NaCl-solution (1 : 1)
No. with + reactions:
0
Total no. in group:
5
Clinical observations:
not reported
Remarks on result:
no indication of skin sensitisation
Reading:
2nd reading
Hours after challenge:
48
Group:
negative control
Dose level:
Freund's adjuvant / 90% aqueous NaCl-solution (1 : 1)
No. with + reactions:
0
Total no. in group:
10
Clinical observations:
not reported
Remarks on result:
no indication of skin sensitisation
Reading:
1st reading
Hours after challenge:
24
Group:
positive control
Dose level:
Alpha-Hexylcinnamaldehyde 85%
No. with + reactions:
14
Total no. in group:
20
Clinical observations:
not reported
Remarks on result:
positive indication of skin sensitisation
Reading:
2nd reading
Hours after challenge:
48
Group:
positive control
Dose level:
Alpha-Hexylcinnamaldehyde 85%
No. with + reactions:
10
Total no. in group:
20
Clinical observations:
not reported
Remarks on result:
positive indication of skin sensitisation
Interpretation of results:
GHS criteria not met
Conclusions:
Based on the evaluation criteria cited under 3.6. the results of this study show that 2.3-Butandiol does not have a sensitizing effect on the skin of the guinea pig in the Maximization Test under the test conditions chosen.
Executive summary:

The study used as source investigated skin sensitisation to guinea pig after induction with 25 % test substance and challenge with 50 % test substance. The study results of the source compound were considered applicable to the target compound, and were used for classification and labelling acc. to Regulation (EC) No 1272/2008. Justification and applicability of the read-across approach (structural analogue) is outlined in the read-across report in section 13

Endpoint:
skin sensitisation: in vivo (non-LLNA)
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Qualifier:
according to
Guideline:
OECD Guideline 406 (Skin Sensitisation)
Deviations:
no
GLP compliance:
yes (incl. certificate)
Type of study:
guinea pig maximisation test
Justification for non-LLNA method:
A valid skin sensitisation study was available from 2002 (before REACh came into force) and therefore no additional LLNA test was performed.
Species:
guinea pig
Sex:
female
Route:
intradermal
Vehicle:
water
Concentration / amount:
test substance in 25% doubly distilled water
Route:
epicutaneous, occlusive
Vehicle:
water
Concentration / amount:
test substance in 25% doubly distilled water
No. of animals per dose:
10
Positive control substance(s):
yes
Remarks:
Alpha-Hexylcinnamaldehyde
Key result
Reading:
1st reading
Hours after challenge:
24
Group:
test group
Dose level:
25% test substance preparation
No. with + reactions:
0
Total no. in group:
10
Clinical observations:
not reported
Remarks on result:
no indication of skin sensitisation
Key result
Reading:
2nd reading
Hours after challenge:
48
Group:
test group
Dose level:
25% test substance preparation
No. with + reactions:
0
Total no. in group:
10
Clinical observations:
not reported
Remarks on result:
no indication of skin sensitisation
Reading:
1st reading
Hours after challenge:
24
Group:
negative control
Dose level:
Freund's adjuvant / 90% aqueous NaCl-solution (1 : 1)
No. with + reactions:
0
Total no. in group:
5
Remarks on result:
no indication of skin sensitisation
Reading:
2nd reading
Hours after challenge:
48
Group:
negative control
Dose level:
Freund's adjuvant / 90% aqueous NaCl-solution (1 : 1)
No. with + reactions:
0
Total no. in group:
5
Clinical observations:
not reported
Remarks on result:
no indication of skin sensitisation
Reading:
1st reading
Hours after challenge:
24
Group:
positive control
Dose level:
Alpha-Hexylcinnamaldehyde 85%
No. with + reactions:
14
Total no. in group:
20
Remarks on result:
positive indication of skin sensitisation
Remarks:
a separate study is performed twice a year in the laboratory
Reading:
2nd reading
Hours after challenge:
48
Group:
positive control
Dose level:
Alpha-Hexylcinnamaldehyde 85%
No. with + reactions:
10
Total no. in group:
20
Clinical observations:
not reported
Remarks on result:
positive indication of skin sensitisation
Interpretation of results:
GHS criteria not met
Conclusions:
Based on the evaluation criteria cited under 3.6. the results of this study show that 2.3-Butandiol does not have a sensitizing effect on the skin of the guinea pig in the Maximization Test under the test conditions chosen.
Executive summary:

After the intradermal induction intense erythema and swelling were observed at the injection sites of all control group animals and all test group animals at which only Freund's adjuvant/0.9% aqueous NaCI-solution was applied. At the injection sites of a 5% test substance preparation in Freund's adjuvant/0.9% aqueous NaCI-solution intense erythema and swelling were seen in all test group animals. Injections of a 5% test substance preparation in 0.9% aqueous NaCI-solution caused moderate and confluent erythema and swelling in all test group animals. The control group animals, injected with 0.9% aqueous NaCI-solution did not show any skin reaction. A 50% formulation of 0.9% aqueous NaCI-solution with Freund's adjuvant/0.9% aqueous NaCI-solution caused intense erythema and swelling in all control group animals. The epicutaneous induction with a 50% test substance preparation in doubly distilled water led to incrustation, partially open (caused by the intradermal induction) and moderate and confluent erythema with swelling in all test group animals.

The challenge with a 25% test substance preparation in doubly distilled water did not cause any skin reactions neither in control group 1 nor in the test group 24 and 48 hours after removal of the patches. Since no borderline results were observed, a 2nd challenge was not performed. Control group 2, that had been intended for a potential 2nd challenge was not applied and therefore not reported.

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed (not sensitising)
Additional information:

No key study is available on skin sensitisation for the submission substance. However, adequate and reliable data are reported here for a structural analogue (source substance 2,3 -Butandiol). Please also refer to the read-across justification document.

In the available key study, 2,3-Butandiol does not have a sensitizing effect on the skin of the guinea pig in the Maximization Test under the test conditions chosen.

In a supporting study performed with the submission substance, skin sensitisation of (2R,3S)-butane-2,3-diol was predicted using the OECD QSAR Toolbox 4.2 automated workflow (Read-across analysis, executed via Automated "Skin sensitization"). No adaptations such as data pruning were performed, and the automated prediction was accepted as valid by the programme.

Prediction summary

Predicted endpoint: EC3, Skin sensitisation; No effect specified; No species specified; No duration

specified; No guideline specified

Predicted value: Negative

Unit/scale: Skin sensitisation II (ECETOC)

Data gap filling method: Read-across analysis, executed via Automated "Skin sensitization"

 

2,3-butanediol ((2R,3S)-rich) is not sensitising to skin (negative). Therefore, (2R,3S)-butane-2,3-diol is not expected to cause allergic skin reactions to humans. The prediction was considered reliable and adequate to be used in human hazard assessment.

Respiratory sensitisation

Endpoint conclusion
Endpoint conclusion:
no study available

Justification for classification or non-classification

No classification and labelling for skin sensitisation is necessary according to the Regulation (EC) No 1272/2008 based on the available data. No data is available on respiratory sensitisation.