Tetrahydrogen [29H,31H-phthalocyanine-2,9,16,23-tetrasulphonato(6-)-N29,N30,N31,N32]cobaltate(4-)

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

Justification for type of information:

In vitro methods not applicable, therefore in vivo was conducted.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

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:

Tetrahydrogen [29H,31H-phthalocyanine-2,9,16,23-tetrasulphonato(6-)-N29,N30,N31,N32]cobaltate(4-)

EC Number:

238-200-7

EC Name:

Tetrahydrogen [29H,31H-phthalocyanine-2,9,16,23-tetrasulphonato(6-)-N29,N30,N31,N32]cobaltate(4-)

Cas Number:

14285-59-7

Molecular formula:

C32H16CoN8O12S4

IUPAC Name:

tetrahydrogen [29H,31H-phthalocyanine-2,9,16,23-tetrasulphonato(6-)-N29,N30,N31,N32]cobaltate(4-)

Specific details on test material used for the study:

The solubility of the test item was examined in a short Preliminary Compatibility Test. The following standard OECD vehicles were assessed: AOO (acetone:olive oil 4:1 (v:v) mixture), N,N-dimethylformamide (DMF), Methyl ethyl ketone (MEK), Propylene glycol (PG), Dimethyl sulfoxide (DMSO) and 1% aqueous Pluronic® PE9200 (1% Pluronic). The best vehicle taking into account the test item characteristics and the requirements of the relevant OECD guideline was considered to be DMSO. The highest achievable concentration based on the regulatory requirements of the OECD guideline and the physical characteristics of the test item was 25 % (w/v). The formulations at 10% (w/v), 5% (w/v), 2% (w/v) and 1% (w/v) in DMSO were also suitable for treatment. Dark (blue) dense formulation (suspension) was observed at 25% (w/v) and 10% (w/v) concentrations and dark (blue) suspension was observed at 5%, 2% and 1% (w/v) concentrations by visual examination. None of the normal vehicles produces a solution at these concentrations.

In vivo test system

Test animals

Species:

mouse

Strain:

CBA

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Envigo
- Females (if applicable) nulliparous and non-pregnant: yes
- Age at study initiation: 11 weeks old (age-matched, within one week)
- Weight at study initiation: 21.3 – 23.6 grams (The weight variation in animals in the study did not exceed ± 20 % of the mean weight.)
- Housing:
- Diet (e.g. ad libitum): ad libidum
- Water (e.g. ad libitum): ad libidum
- Acclimation period: 28 days


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 18.3 – 24.8°C
- Humidity (%): 22 - 67 %
- Air changes (per hr): 15-20 air exchanges/hour
- Light 12 hours daily, from 6.00 a.m. to 6.00 p.m.

Study design: in vivo (LLNA)

Vehicle:

dimethyl sulphoxide

Concentration:

2%
5%
10%
25%

No. of animals per dose:

4

Details on study design:

PRE-SCREEN TESTS:
- Compound solubility: Based on the observation of the solubility test, the maximum available concentration was 25% (w/v).
- Irritation: There were no indications of any irritancy at the site of application.
- Systemic toxicity: no mortality or signs of systemic toxicity were observed.
- Ear thickness measurements: Both ears of each mouse were observed for erythema. Ear thickness was also measured using a thickness gauge on Day 1 (pre-dose), Day 3 (approximately 48 hours after the first dose) and Day 6. Additional quantification of the ear thickness was performed by ear punch weight determination after the euthanasia of the experimental animals.

ANIMAL ASSIGNMENT AND TREATMENT
- Criteria used to consider a positive response:
The test item is regarded as a sensitizer if both of the following criteria are fulfilled:
- That exposure to at least one concentration of the test item resulted in an incorporation of 3HTdR at least 3-fold or greater than recorded in control mice, as indicated by the stimulation index.
- The data are compatible with a conventional dose response, although allowance must be made (especially at high topical concentrations) for either local toxicity or immunological suppression.

Positive control substance(s):

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

Results and discussion

Positive control results:

The positive control substance produces a significant lymphoproliferative response increases (SI>3)

In vivo (LLNA)

Results

Results 1

Key result

Parameter:

SI

Value:

5

Test group / Remarks:

Test group 25%

Results 2

Key result

Parameter:

SI

Value:

6.4

Test group / Remarks:

Test group 10%

Results 3

Key result

Parameter:

SI

Value:

5.9

Test group / Remarks:

Test group 5%

Results 4

Key result

Parameter:

SI

Value:

3.7

Test group / Remarks:

Test group 2%

Results 5

Parameter:

SI

Value:

5

Test group / Remarks:

Positive control

Results 6

Parameter:

SI

Value:

1

Test group / Remarks:

Negative control

Cellular proliferation data / Observations:

The appearance of the lymph nodes was normal in the negative control. Larger than normal lymph nodes were observed in all test item treated groups and in the positive control group.

Any other information on results incl. tables

Since the test item gave a positive response and data permitted, the EC3 value of the test item was calculated (EC3 means the effective chemical concentration required for SI=3). The calculation of the EC3 value was conducted by log-linear interpolation.

The extrapolated EC3 value is 1.5% (w/v).

Applicant's summary and conclusion

Interpretation of results:

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

Conclusions:

In conclusion, under the conditions of the present assay, the test item was shown to have sensitization potential in the Local Lymph Node Assay. The extrapolated EC3 value (that is, the effective chemical concentration required for SI=3) is 1.5% (w/v).
According to Regulation (EC) No 1272/2008 (CLP) and GHS criteria, the test item should be classified in Skin Sensitisation, Category 1 (sub-category 1A) - H317 May cause an allergic skin reaction.