Methylium, triphenyl-, tetrakis(pentafluorophenyl)borate(1-).

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2 - 30 October 2006

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2006

Report date:

2006

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

April 2002

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.42 (Skin Sensitisation: Local Lymph Node Assay)

Version / remarks:

April 2004

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:

-

EC Number:

472-690-5

EC Name:

-

Cas Number:

136040-19-2

Molecular formula:

C24BF20.C19H15

IUPAC Name:

Methylium, triphenyl-, tetrakis(pentafluorophenyl)borate(1-).

Test material form:

solid: particulate/powder

In vivo test system

Test animals

Species:

mouse

Strain:

CBA

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Charles River France, L'Arbresle Cedex, France
- Females (if applicable) nulliparous and non-pregnant: yes
- Age at study initiation: approx. 11 weeks
- Weight at study initiation: 20-26 g
- Housing: individual housing in labeled Macrolon cages containing sterilized sawdust as bedding material
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: at least 5 days before the start of treatment under lab conditions

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20.1-23.3 C
- Humidity (%): 42-89%
- Air changes (per hr): 15
- Photoperiod (hrs dark / hrs light): 12/12

Study design: in vivo (LLNA)

Vehicle:

methyl ethyl ketone

Concentration:

0%, 0.05%, 0.1%, 0.25%

No. of animals per dose:

5

Details on study design:

PRE-SCREEN TESTS:
- Doses: 0.25-0.5-1-2.5-5-10-25-50% test substance in methyl ethyl keton
- Systemic toxicity: noted at dose levels 25% (hunched posture) and 50% (sacrificed)
- Erythema scores: ranging between 2 and 3 on day 3 of all doses tested, oedema score was 0.

Positive control substance(s):

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

Results and discussion

Positive control results:

Six monthly reliability check at 5%, 10% and 25%: EC3 value of 13.1%.

In vivo (LLNA)

Results

Results 1

Key result

Parameter:

SI

Value:

3.5

Test group / Remarks:

0.05%

Results 2

Key result

Parameter:

SI

Value:

9.8

Test group / Remarks:

0.1%

Results 3

Key result

Parameter:

SI

Value:

6.7

Test group / Remarks:

0.25%

Cellular proliferation data / Observations:

Erythema was observed in all animals while no oedema was noted. The irritation of the ears was considered not to have a toxicologically significant effect on the activity of the nodes. All nodes of the control and 0.05% treated groups were normal in size and the majority of the nodes of animals treated at 0.1% and 0.25% were increased in size. No macroscopic abnormalities of the surrounding area were noted. No adverse effects on body weight were noted.
No mortality occurred and no symptoms of systemic toxicity were observed in the animals of the main study.

Applicant's summary and conclusion

Interpretation of results:

Category 1 (skin sensitising) based on GHS criteria

Conclusions:

The results indicate that the test substance could elicit a SI >= 3. No reliable EC3 value could be calculated as the response of the 0.25% group did not follow the expected dose-response relationship. Since systemic toxicity was evident at higher dose levels, the response of the 0.25% concentration might be less due to underlying systemic toxicity. Based on these results, the substance would be regarded as a skin sensitiser.