Registration Dossier

Administrative data

Description of key information

- Skin sensitisation (Buehler, OECD 406): not sensitising

- Skin sensitisation (LLNA, OECD 429): not sensitising

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:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Qualifier:
according to guideline
Guideline:
OECD Guideline 406 (Skin Sensitisation)
GLP compliance:
yes
Type of study:
Buehler test
Justification for non-LLNA method:
A non-LLNA test is available that was performed prior to the current data requirements, stipulated in Regulation (EC) No 1907/2006. In accordance with the same Regulation, the data was included to avoid unnecessary testing.
Species:
guinea pig
Strain:
Hartley
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Elm Hill Breeding Labs, Chelmsford, MA
- Weight at study initiation: 292-352 gms
- Housing:
- Diet: ad libitum
- Water:ad libitum
- Acclimation for at least 5 days

ENVIRONMENTAL CONDITIONS
- Photoperiod (hrs dark / hrs light): 12 hrs

IN-LIFE DATES: From: 01/04/2009 To: 08/05/09
Route:
epicutaneous, occlusive
Vehicle:
corn oil
Concentration / amount:
100%
Route:
epicutaneous, occlusive
Vehicle:
corn oil
Concentration / amount:
25%
No. of animals per dose:
10 M/10 F
Details on study design:
RANGE FINDING TESTS: non irritating dose = 25%

MAIN STUDY
A. INDUCTION EXPOSURE
- No. of exposures: 3
- Frequency of applications: once a week
- Duration: 3 weeks
- Concentrations: 100%


B. CHALLENGE EXPOSURE
- No. of exposures: 1
- Day(s) of challenge: 2 weeks following last induction
- Concentrations: 25%
- Evaluation (hr after challenge): 24 and 48 hours

Positive control substance(s):
yes
Remarks:
HCA
Positive control results:
Testing with 85% hexylcinnamaldehyde are confirmed in the laboratory every 6 months. Data from the study conducted in summer 2009 included with results as expected.
Reading:
1st reading
Hours after challenge:
24
Group:
negative control
Dose level:
25%
No. with + reactions:
0
Total no. in group:
10
Reading:
2nd reading
Hours after challenge:
48
Group:
negative control
Dose level:
25%
No. with + reactions:
0
Total no. in group:
10
Key result
Reading:
1st reading
Hours after challenge:
24
Group:
test chemical
Dose level:
25%
No. with + reactions:
1
Total no. in group:
20
Key result
Reading:
2nd reading
Hours after challenge:
48
Group:
test chemical
Dose level:
25%
No. with + reactions:
0
Total no. in group:
20
Group:
positive control
Remarks on result:
positive indication of skin sensitisation
Interpretation of results:
other: CLP/EU GHS criteria not met, no classification required according to Regulation (EC) No 1272/2008
Conclusions:
2-PO (MPKO) is not a skin sensitizer under conditions of this study.
Endpoint:
skin sensitisation: in vivo (LLNA)
Type of information:
experimental study
Adequacy of study:
supporting study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Qualifier:
according to guideline
Guideline:
OECD Guideline 429 (Skin Sensitisation: Local Lymph Node Assay)
GLP compliance:
yes (incl. QA statement)
Remarks:
Food and Consumer Product Safety Authority (VWA), Den Haag, The Netherlands
Type of study:
mouse local lymph node assay (LLNA)
Species:
mouse
Strain:
CBA
Sex:
female
Vehicle:
acetone/olive oil (4:1 v/v)
Concentration:
25%, 50%, and 100%
No. of animals per dose:
5
Key result
Parameter:
SI
Value:
1.5
Test group / Remarks:
25%
Key result
Parameter:
SI
Value:
1.1
Test group / Remarks:
50%
Key result
Parameter:
SI
Value:
1.3
Test group / Remarks:
100%
Interpretation of results:
other: CLP/EU GHS criteria not met, no classification required according to Regulation (EC) No 1272/2008
Conclusions:
2-PO (MPKO) was not a skin sensitizer in the LLNA study.
Endpoint conclusion
Endpoint conclusion:
no adverse effect observed (not sensitising)
Additional information:

A Buehler test was performed with 2-pentanone oxime (2-PO; CAS 623-40-5) under GLP and according to OECD Guideline 406 (Key, 2009). Based on the results of a dose range-finding study, ten male and 10 female guinea pigs of the Hartley strain were induced with test item (100%) moistened in corn oil for 6 h during topical induction. The animals were induced under occlusive conditions once per week for an induction period of three weeks in total. A similar constituted group of 10 animals remained untreated and served as control. The epicutaneous challenge exposure was conducted two weeks after the third induction. Test and control animals received a dermal exposure of test substance (25% in corn oil) for 6 h under occlusive conditions. Local skin reactions were evaluated 24 and 48 h after removal of the patches. There was only one animal of the test group showing skin reactions 24 h after removal of the patches for the challenge. However, no animal of the test group showed skin reactions 48h after the removal of the patches for the challenge. Negative and positive (85% hexylcinnamaldehyde) controls showed expected results, thus confirming the reliability and sensitivity of the test system. In summary, based on the available data the test substance is not considered as skin sensitiser.

A Local Lymph Node Assay was performed with 2-PO (CAS 623-40-5) under GLP according to OECD Guideline 429 (Supporting, 2009). Ear skins of 5 female CBA mice were treated with 2-PO at concentrations of 25, 50 and 100% diluted with acetone/olive oil (4:1 v/v). The SI values were 1.5, 1.1 and 1.3 for the test groups treated with 25%, 50% and 100%, respectively. Thus, based on the study result, the test substance is not a skin sensitiser.

Respiratory sensitisation

Endpoint conclusion
Endpoint conclusion:
no study available

Justification for classification or non-classification

The available data on skin sensitisation do not meet the criteria for classification according to Regulation (EC) 1272/2008 and are therefore conclusive but not sufficient for classification.