sodium 4-[(4-chlorobenzoyl)amino]benzoate

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: GLP guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2014

Report date:

2014

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

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:

sodium 4-[(4-chlorobenzoyl)amino]benzoate

EC Number:

807-461-4

Cas Number:

1489170-67-3

Molecular formula:

C14H9ClNNaO3

IUPAC Name:

sodium 4-[(4-chlorobenzoyl)amino]benzoate

Test material form:

solid: particulate/powder

Remarks:

migrated information: powder

Details on test material:

- Storage condition of test material: room temperature in the dark
- Description: white powder

In vivo test system

Test animals

Species:

mouse

Strain:

other: CBA/Ca (CBA/CaOlaHsd)

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Female CBA/Ca (CBA/CaOlaHsd) strain mice were supplied by Harlan Laboratories UK Ltd., Oxon, UK
- Age at study initiation: eight to twelve weeks
- Weight at study initiation: 15 to 23 g
- Housing: individually housed in suspended solid floor polypropylene cages furnished with softwood woodflakes
- Diet (e.g. ad libitum) and water (e.g. ad libitum): Free access to mains tap water and food (2014C Teklad Global Rodent diet supplied by Harlan Laboratories UK Ltd., Oxon, UK) was allowed throughout the study
- Acclimation period: at least five days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19 to 25 °C
- Humidity (%): 30 to 70%
- Air changes (per hr): approximately fifteen changes per hour
- Photoperiod (hrs dark / hrs light): twelve hours continuous light (06.00 to 18.00) and twelve hours darkness

Study design: in vivo (LLNA)

Vehicle:

other: 1% pluronic L92 in distilled water

Concentration:

Preliminary screening test: maximum attainable concentration of 10% w/w in 1% pluronic L92 in distilled water
Main test: 10%, 5% or 2.5% (w/w) in 1% pluronic L92 in distilled water

No. of animals per dose:

Preliminary screening test: one mouse
Main test: groups of four mice

Details on study design:

RANGE FINDING TESTS:
- Compound solubility: Not stated in report
- Irritation: None
- Lymph node proliferation response: The proliferation response of lymph node cells was expressed as the number of radioactive disintegrations per minute per lymph node (disintegrations per minute/node) and as the ratio of 3HTdR incorporation into lymph node cells of test nodes relative to that recorded for the control nodes (Stimulation Index).

MAIN STUDY
ANIMAL ASSIGNMENT AND TREATMENT:
- Name of test method: Local Lymph Node Assay in the Mouse
- Criteria used to consider a positive response: The test item will be regarded as a sensitizer if at least one concentration of the test item results in a threefold or greater increase in3HTdR incorporation compared to control values. Any test item failing to produce a threefold or greater increase in3HTdR incorporation will be classified as a non-sensitizer.

TREATMENT PREPARATION AND ADMINISTRATION:
Groups of four mice were treated with the test item at concentrations of 10%, 5% or 2.5% w/w in 1% pluronic L92 in distilled water. The preliminary screening test suggested that the test item would not produce systemic toxicity or excessive local skin irritation at the highest suitable concentration. The mice were treated by daily application of 25 µL of the appropriate concentration of the test item to the dorsal surface of each ear for three consecutive days (Days 1, 2, 3). The test item formulation was administered using an automatic micropipette and spread over the dorsal surface of the ear using the tip of the pipette.
A further group of four mice received the vehicle alone in the same manner.
3H-Methyl Thymidine Administration:
Five days following the first topical application of the test item or vehicle (Day 6) all mice were injected via the tail vein with 250 µL of phosphate buffered saline (PBS) containing 3H-methylthymidine (3HTdR: 80 µCi/mL, specific activity 2.0 Ci/mmoL, ARC UK Ltd) giving a total of 20 µCi to each mouse.

Positive control substance(s):

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

Results and discussion

Positive control results:

The Stimulation Index expressed as the mean radioactive incorporation for each treatment group divided by the mean radioactive incorporation of the vehicle control group are as follows:
Concentration (% v/v) in 1% pluronic L92 in distilled water: 25
Stimulation Index: 4.66
Result: Positive

Conclusion: alpha Hexylcinnamaldehyde was considered to be a sensitiser under the conditions of the test.

In vivo (LLNA)

Results

Results 1

Parameter:

SI

Remarks on result:

other: 2.5 % concentration: 0.74 5 % concentration: 1.04 10 % concentration: 1.04

Results 2

Parameter:

other: disintegrations per minute (DPM)

Remarks on result:

other: 2.5 % concentration: 9329.85 5 % concentration: 13156.43 10 % concentration: 13153.05

Applicant's summary and conclusion

Interpretation of results:

not sensitising

Remarks:

Migrated information Criteria used for interpretation of results: other: EU GHS

Conclusions:

The test substance was considered to be non-sensitising under the conditions of this test. The study was performed under GLP according to OECD guideline 429 and EU Method B.42 and therefore reliability of Klimisch 1 has been assigned.