Merbromin

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Justification for type of information:

Data is from peer reviewed journal.

Data source

Reference

Reference Type:

publication

Title:

Gold dermatitis due to ear piercing: correlations between gold and mercury hypersensitivities

Author:

Junko Osawa, Kazuko Kitamura, Zenro Ikezawa, Takeshi Hariya, Hiroshi Nakajima

Year:

1994

Bibliographic source:

Contact Dermatitis Volume 31, Issue 2 August 1994 Pages 89–91

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: An Adjuvant patch tes

Principles of method if other than guideline:

An Adjuvant patch test was conducted on five male Hartley guinea pigs to examine the sensitization effects caused by the test chemical

GLP compliance:

not specified

Type of study:

other: Adjuvant patch test

Justification for non-LLNA method:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

Merbromin

EC Number:

204-933-6

EC Name:

Merbromin

Cas Number:

129-16-8

Molecular formula:

C20H10Br2HgO6.2Na

IUPAC Name:

merbromin

Test material form:

solid: crystalline

Details on test material:

- Name of test material: disodium [2,7-dibromo-9-(2-carboxylatophenyl)-6-oxido-3-oxo-3H-xanthen-5-yl]mercurol
- Common name : Merbromin
- Molecular formula: C20H8Br2HgNa2O6
- Molecular weight: 750.6552 g/mol
- Smiles notation: c1ccc2c(c1)C(=O)OC23c4cc(c(cc4Oc5c3cc(c(c5[Hg]O)[O-])Br)[O-])Br.[Na+].[Na+]
- InChl: 1S/C20H9Br2O5.Hg.2Na.H2O/c21-13-5-11-17(7-15(13)23)26-18-8-16(24)14(22)6-12(18)20(11)10-4-2-1-3-9(10)19(25)27-20;;;;/h1-7,23-24H;;;;1H2/q;3*+1;/p-3
- Substance type: Organic
- Physical state: Solid

In vivo test system

Test animals

Species:

guinea pig

Strain:

Hartley

Sex:

male

Details on test animals and environmental conditions:

- Source: Funabashi Experimental Animal farm
- Age at study initiation: 400-500 kg

Study design: in vivo (non-LLNA)

Induction

Route:

epicutaneous, occlusive

Vehicle:

other: Distilled water

Concentration / amount:

2%

Day(s)/duration:

9 days

Adequacy of induction:

not specified

Challenge

No.:

#1

Route:

epicutaneous, occlusive

Vehicle:

other: Distilled water

Concentration / amount:

2%

Day(s)/duration:

48 hours

Adequacy of challenge:

not specified

No. of animals per dose:

5

Details on study design:

RANGE FINDING TESTS:

MAIN STUDY
A. INDUCTION EXPOSURE
- No. of exposures: 2
- Exposure period: no data
- Test groups: 5 male
- Control group: yes
- Site: shaved and abraded area of 2 × 4 cm2 nuchal skin, which was defined by 4 injections (0.1mlX4) of emulsified Freund’s complete adjuvant (FCA) at the corners.
- Frequency of applications: daily for 3 days and repeated on 9th day
- Duration: 9 days
- Concentrations: 2% (0.1 ml)

B. CHALLENGE EXPOSURE
- No. of exposures: 1
- Day(s) of challenge:3 weeks
- Exposure period: 48 hours
- Test groups: 5
- Control group: yes
- Site: shaved skin of flank
- Concentrations: 2%
- Evaluation (hr after challenge): after 4 hours

Challenge controls:

Yes concurrent vehicle

Positive control substance(s):

not specified

Results and discussion

In vivo (non-LLNA)

Results

Reading:

1st reading

Hours after challenge:

48

Group:

test chemical

Dose level:

2%

No. with + reactions:

3

Total no. in group:

5

Clinical observations:

3 out of 5 guinea pigs were sensitized with the chemical with mean score of 2.

Remarks on result:

positive indication of skin sensitisation

Applicant's summary and conclusion

Interpretation of results:

other: sensitizing

Conclusions:

3 out of 5 guinea pigs were sensitized with the chemical with mean score of 2.. Thus the chemical was considered to be sensitizing on skin of guinea pigs.

Executive summary:

An Adjuvant patch testwas conducted on five male Hartley guinea pigs to examine the sensitization effects caused by the test chemical

 

The method was described by the Sato et al. and it was a modification of maximization test. The guinea pigs were given single doses of 0.1 ml 2 % merbromin in water, applied occlusively, daily for 3 days on shaved and abraded area of 2 × 4 cm²nuchal skin at the corners of which were 4 FCA injection sites (each FCA injection: 0.1 ml). The epicutaneous treatment was repeated on day 9. On provocation 3 weeks after the beginning of the induction treatment, the guinea pigs were challenged topically with o.o1ml of chemical in distilled water directly to the shaved skin of the flank. Skin reactions were scored after 48 hours.A score greater than 2 was considered positive. The result was expressed as the mean score and frequency of positives. The Wilcoxon-Mann-Whitney test was used for statistical evaluation of the results.

 

3 out of 5 guinea pigs were sensitized with the chemical with mean score of 2. Thus the chemical was considered to be sensitizing on skin of guinea pigs.