4,4'-dihydroxy-7,7'-iminodi(naphthalene-2-sulphonic acid)

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

weight of evidence

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 jounal

Data source

Reference

Reference Type:

publication

Title:

THE PERFORMANCE OF THE LOCAL LYMPH NODE ASSAY WITH CHEMICALS IDENTIFIED AS CONTACT ALLERGENS IN THE HUMAN MAXIMIZATION TEST

Author:

D. A. BASKETTR, E. W. SCHOLES and I. KIMBER

Year:

1994

Bibliographic source:

Food and Chemical Toxicology Vol. 32. No. 6. pp. 543-547. 1994

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

Principles of method if other than guideline:

The Local Lymph Node Assay (LLNA) was conducted on Female CBA/Ca mice to assess the skin sensitization potential of chemical Resorcinol (CAS No: 108-46-3).

GLP compliance:

not specified

Type of study:

mouse local lymph node assay (LLNA)

Justification for non-LLNA method:

not applicable

Test material

Test material information

Constituent 1

Reference substance name:

1,3 benzenediol

Cas Number:

108-46-3

Molecular formula:

C6H6O2

IUPAC Name:

1,3 benzenediol

Test material form:

solid

Details on test material:

- Name of test material (as cited in study report): Resorcinol
- Molecular formula: C6H6O2
- Molecular weight: 110.1114 g/mol
- Substance type: organic
- Physical state: solid
-Smiles: c1c(cccc1O)O
-InChI: 1S/C6H6O2/c7-5-2-1-3-6(8)4-5/h1-4,7-8H

Specific details on test material used for the study:

- Name of test material (as cited in study report): Resorcinol
- Molecular formula: C6H6O2
- Molecular weight: 110.1114 g/mol
- Substance type: organic
- Physical state: solid
-Smiles: c1c(cccc1O)O
-InChI: 1S/C6H6O2/c7-5-2-1-3-6(8)4-5/h1-4,7-8H

In vivo test system

Test animals

Species:

mouse

Strain:

CBA/Ca

Sex:

female

Details on test animals and environmental conditions:

Age at study initiation: 8-12 week.

Study design: in vivo (non-LLNA)

Challenge controls:

Control mice were treated with vehicle alone in an identical manner.

Positive control substance(s):

not specified

Study design: in vivo (LLNA)

Vehicle:

dimethylformamide

Concentration:

25 µl of 5%, 10% and 25%

No. of animals per dose:

4

Details on study design:

Treatment was performed daily for 3 consecutive days with 25 µl of one of three concentrations of the test chemical on the dorsum of each ear. 5 days after the first topical application, all mice were injected iv with 250µl phosphate buffered saline (PBS) containing 20µCi of [3H]methyl thymidine (3HTdR) .The mice were killed 5 hr later and the draining auricular lymph nodes excised and pooled for each experimental group. A single cell suspension of lymph node cells (LNC) was prepared by gentle disaggregation through 200 mesh stainless steel gauze. Pooled LNC were pelleted by centrifugation at 190g for 10 min, washed twice with 10 ml PBS and resuspended in 3 ml 5% trichloroacetic acid (TCA). After incubation overnight at 4°C, the precipitate was recovered by centrifugation, resuspended in 1 ml 5% TCA and transferred to 10 ml scintillation fluid. Incorporation of 3HTdR was measured by p-scintillation counting.

Results and discussion

In vivo (LLNA)

Results

Results 1

Parameter:

other: test: control (T:C) ratio

Value:

2.2

Test group / Remarks:

4

Remarks on result:

other: at concentration of 5% and 10%

Results 2

Parameter:

other: test: control (T:C) ratio

Value:

2.7

Test group / Remarks:

4

Remarks on result:

other: at concentration of 25%

Cellular proliferation data / Observations:

The test: control (T:C) ratio was less than 3 at each concentration.

Applicant's summary and conclusion

Interpretation of results:

other: Not sensitizing

Conclusions:

The resulted test: control (T:C) ratio was less than 3 at each concentration. Hence the chemical Resorcinol (CAS No: 108-46-3) was considered to be not sensitizing in Local Lymph Node Assay (LLNA).

Executive summary:

The Local Lymph Node Assay (LLNA) was conducted on Female CBA/Ca mice to assess the skin sensitization potential of chemical Resorcinol (CAS No: 108-46-3).

 

The LLNA was conducted on groups of CBA/Ca mice (8-12 weeks of age) by mean of topical application of chemical on the dorsum of both ears at a dose of 25µl of one of three concentrations (5%, 10% and 25%)of the test chemical.

 

5 days after the first topical application, all mice were injected iv with 250µl phosphate buffered saline (PBS) containing 20µCi of [³H]methyl thymidine (³HTdR) .The mice were killed 5 hr later and the draining auricular lymph nodes excised and pooled for each experimental group. A single cell suspension of lymph node cells (LNC) was prepared by gentle disaggregation through 200 mesh stainless steel gauze. Pooled LNC were pelleted by centrifugation at 190g for 10 min, washed twice with 10 ml PBS and resuspended in 3 ml 5% trichloroacetic acid (TCA). After incubation overnight at 4°C, the precipitate was recovered by centrifugation, resuspended in I ml 5% TCA and transferred to 10 ml scintillation fluid. Incorporation of³HTdR was measured by p-scintillation counting.

 

The proliferative response of LNC was expressed as mean radioactive disintegrations per minute per lymph node (dpm/node for each experimental group and as the ratio of³HTdR incorporation into LNC of test nodes relative to control nodes [test: control (T:C) ratio]. A chemical was regarded as a sensitizer in the LLNA if at least one concentration resulted in a T:C ratio of 3 or greater and the data were not incompatible with a biological dose response.

 

The test: control (T:C) ratios were 2.2, 2.2 and 2.7 at concentration of 5%, 10% and 25% respectively.

 

Since the resulted test: control (T:C) ratio was less than 3 at each concentration, the chemical Resorcinol (CAS No: 108-46-3) was considered to be not sensitizing in Local Lymph Node Assay (LLNA).