Sulphanilic acid

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:

other: Study according to OECD test guideline 429 under GLP

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2010

Report date:

2010

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

Deviations:

yes

Remarks:

relative humidity out of range without any impact on study

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:

Sulphanilic acid

EC Number:

204-482-5

EC Name:

Sulphanilic acid

Cas Number:

121-57-3

Molecular formula:

C6H7NO3S

IUPAC Name:

4-aminobenzene-1-sulfonic acid

Details on test material:

Identity:Sulfanilic Acid (sieved)
Batch No.:M 002/10
Purity:98.5%
Storage:At room temperature, moisture protected
Expiration Date:May 01, 2012

In vivo test system

Test animals

Species:

mouse

Strain:

CBA

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Harlan Laboratories B.V., Postbus 6174, 5960 AD Horst / The Netherlands
- Age at study initiation: 8-12 weeks
- Weight at study initiation: 17.8 -22.1 g
- Housing: single caging (Makrolon Type II, with wire mesh top) with granulated soft wood bedding
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 + 2°C
- Humidity (%): 39-81 %
- Air changes (per hr): -
- Photoperiod (hrs dark / hrs light): 12/12

Study design: in vivo (LLNA)

Vehicle:

propylene glycol

Concentration:

5, 10, 25%

No. of animals per dose:

4

Details on study design:

MAIN STUDY
ANIMAL ASSIGNMENT AND TREATMENT
- Name of test method: LLNA
- Criteria used to consider a positive response:
A test item is regarded as a sensitiser in the LLNA if the following criteria are fulfilled:
- First, that exposure to at least one concentration of the test item resulted in an incorporation of 3HTdR at least 3-fold or greater than that recorded in control mice, as indicated by the stimulation index.
- Second, that 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.

TREATMENT PREPARATION AND ADMINISTRATION:
Each test group of mice was treated by topical (epidermal) application to the dorsal surface of each ear (left and right) with different test item concentrations of 5, 10, and 25% (w/w) in propylene glycol. The application volume, 25 µl, was spread over the entire dorsal surface (0 - 8 mm) of each ear once daily for three consecutive days. A further group of mice was treated with an equivalent volume of the relevant vehicle alone (control animals).

Positive control substance(s):

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

Results and discussion

Positive control results:

The sensitivity and reliability of the experimental technique employed was assessed by use of a-hexyl cinnamaldehyde dissolved in acetone:olive oil (4:1 v/v) (compound listed in OECD 429 Guideline) which is known to have skin sensitisation properties in mice, CBA/CaOlaHsd. The validation- / positive control experiment was performed with a-Hexylcinnamaldehyde in acetone:olive oil (4+1) using CBA/CaOlaHsd mice in May 2010,

In vivo (LLNA)

Results

Results 1

Parameter:

SI

Remarks on result:

other: 5%: 0.84 10%: 0.98 25%: 0.79

Results 2

Parameter:

other: disintegrations per minute (DPM)

Remarks on result:

other: negative control group: 2495 5%: 2101 10%: 2453 25%: 1966

Applicant's summary and conclusion

Interpretation of results:

not sensitising

Remarks:

Migrated information

Conclusions:

in a study according to OECD test guideline 429 under GLP, the test substance was determined to be not skin sensitising.

Executive summary:

In the study (acc. to OECD test guideline 429) the test substance suspended in propylene glycol was assessed for its possible contact allergenic potential. For this purpose a local lymph node assay was performed using test item concentrations of 5, 10, and 25%. The animals did not show any clinical signs during the course of the study and no cases of mortality were observed. A test item is regarded as a sensitiser in the LLNA if the exposure to one or more test concentration resulted in 3-fold or greater increase in incorporation of 3HTdR compared with concurrent controls, as indicated by the Stimulation Index (S.I.). The estimated concentration of test item required to produce a S.I. of 3 is referred to as the EC3 value. In this study Stimulation Indices (S.I.) of 0.84, 0.98, and 0.79 were determined with the test item at concentrations of 5, 10, and 25% in propylene glycol, respectively. The test substance was not a skin sensitiser in this assay.