Bis(pentane-2,4-dionato-O,O')zinc

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:

2012

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

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:

Bis(pentane-2,4-dionato-O,O')zinc

EC Number:

237-860-3

EC Name:

Bis(pentane-2,4-dionato-O,O')zinc

Cas Number:

14024-63-6

Molecular formula:

C10H14O4Zn

IUPAC Name:

zinc bis(4-oxopent-2-en-2-olate)

Test material form:

solid: particulate/powder

In vivo test system

Test animals

Species:

mouse

Strain:

CBA/Ca

Sex:

female

Details on test animals and environmental conditions:

Test animals were supplied by Harlan Laboratories UK Ltd., Oxon, UK.

Study design: in vivo (LLNA)

Vehicle:

dimethyl sulphoxide

Concentration:

The animals were treated with 50 μI (25 μI per ear) of the test item as a solution in dimethyl sulphoxide at concentrations of 25%, 10% or 5% w/w, respectively.

No. of animals per dose:

Three groups, each of five animals, were used to conduct the test.

Positive control substance(s):

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

Results and discussion

Positive control results:

a-Hexylcinnamaldehyde, tech., 85% gave a Stimulation Index of greater than 3 when tested at a concentration of 25% v/v in dimethyl sulphoxide.

In vivo (LLNA)

Results

Results 1

Key result

Parameter:

EC3

Remarks:

EC3 value calculated based on 3 test results

Value:

11

Results 2

Key result

Parameter:

SI

Value:

2.33

Test group / Remarks:

5% w/w in dimethyl sulphoxide

Results 3

Key result

Parameter:

SI

Value:

2.94

Test group / Remarks:

10% w/w in dimethyl sulphoxide

Results 4

Key result

Parameter:

SI

Value:

3.94

Test group / Remarks:

25% w/w in dimethyl sulphoxide

Any other information on results incl. tables

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	Concentration	Stimulation index	Result
Test item	5% w/w in dimethyl sulphoxide	2.33	Negative
Test item	10% w/w in dimethyl sulphoxide	2.94	Negative
Test item	25% w/w in dimethyl sulphoxide	3.94	Positive
Positive control item	25% v/v dindimethyl sulphoxide	8.24	Positive

The concentration of test item expected to cause a 3 fold increase in 3HTdR incorporation (EC3 value) was calculated to be 11 %.

Applicant's summary and conclusion

Interpretation of results:

Category 1 (skin sensitising) based on GHS criteria

Conclusions:

The concentration of test item expected to cause a 3 fold increase in 3HTdR incorporation (EC3 value) was calculated to be 11 %.
At a concentration of 25% w/w in dimethyl sulphoxide the test item caused a stimulation index of 3.94.
The test item was considered to be a sensitiser category 1B under the conditions of the test.

Executive summary:

According to Regulation (EC) No 1272/2008, chapter 3.4.2.2.3.1, a classification as a skin sensitiser category 1B has to be applied:

The EC3 value is above 2 %