2-Propenoic acid, (2,2-dimethyl-1,3-dioxolan-4-yl)methyl ester

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2019

Report date:

2019

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of study:

mouse local lymph node assay (LLNA)

Test material

Test material information

Constituent 1

Reference substance name:

(2,2-dimethyl-1,3-dioxolan-4-yl)methyl prop-2-enoate

EC Number:

814-155-4

Cas Number:

13188-82-4

Molecular formula:

C9H14O4

IUPAC Name:

(2,2-dimethyl-1,3-dioxolan-4-yl)methyl prop-2-enoate

Test material form:

liquid

In vivo test system

Test animals

Species:

mouse

Strain:

CBA/Ca

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Envigo RMS GmbH, NL-5800 AN Venray
- Age at study initiation: 8 - 12 weeks
- Weight at study initiation: 17.7 g – 18.7 g (pretest); 17.0 g – 21.8 g (main test)
- Housing: single housing (Polycarbonate cages type MII with mesh wire tops)
- Diet (e.g. ad libitum): Mouse and rat maintenance diet “GLP”, Granovit AG, Kaiseraugst, Switzerland; ad libitum
- Water (e.g. ad libitum): drinking water; ad libitum
- Acclimation period: at least 5 days before the first application

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 – 24°C
- Humidity (%): 45 – 65%
- Photoperiod (hrs dark / hrs light): 12/12

Study design: in vivo (LLNA)

Vehicle:

methyl ethyl ketone

Concentration:

1, 5 and 10%

No. of animals per dose:

5

Positive control substance(s):

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

Statistics:

Mean values and standard deviations of the measured parameters were calculated per test group from the individual values. The stimulation indices of 3H-thymidine incorporation, cell count, lymph node weight and ear weight measurements were calculated by dividing the mean values and/or single animal values of the test substance treated groups by the mean of the vehicle treated group.
3H-thymidine incorporation, cell count, lymph node weight and ear weight (WILCOXON-Test)

Results and discussion

In vivo (LLNA)

Results

Results 1

Parameter:

EC3

Remarks:

%

Value:

6.2

Results 2

Parameter:

other: EC1.5 %

Value:

5.3

Any other information on results incl. tables

Test Group	Treatment	^3H-thymidine incorporation Stimulattion Index^1	Cell Count Stimulation Index^1	Lymph Node Weight Stimulatin Index^1	Ear Weight Stimulation Index^1
1	Vehicle MEK	1.00	1.00	1.00	1.00
2	1% in MEK	1.40	1.17	1.01	0.97
3	5% in MEK	2.17  ##	1.44 ##	1.19 #	0.96
4	10% in MEK	5.76  ##	2.40 ##	1.82 ##	0.99

 ¹versus mean of test group 1 (vehicle control)

The statistical evaluations were performed using the WILCOXON-test ( # for p≤0.05, ##for p≤0.01)

Applicant's summary and conclusion

Interpretation of results:

Category 1B (indication of skin sensitising potential) based on GHS criteria

Conclusions:

Thus, it is concluded that Laromer IPGA exhibits a skin sensitizing potential in the Murine Local Lymph Node Assay under the test conditions chosen.
The threshold concentration for sensitization induction was >5% <10%. The EC 3 (estimated concentration that leads to the SI of 3.0) for 3H-thymidine incorporation and the EC 1.5 (estimated concentration that leads to the SI of 1.5) for cell count was calculated by linear regression from the results of these concentrations to be 6.2% and 5.3%, respectively.