Sodium N-(2-carboxyethyl)-N-dodecyl-β-alaninate

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1963

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1963

Report date:

1963

Materials and methods

Principles of method if other than guideline:

The testing method was based on the Draize test as described in Draize et al. (1944), J Pharm and Exp Ther 82. Each of ten guinea pigs received a series of 10 injections of 0.1% test item solution, every other day, in a depilated skin region below the midline of the back. The first injected volume was 0.05 mL, the following injected volumes were 0.1 mL each. After 2 weeks following the last induction injection, challenge was conducted by injection of 0.05 mL of the test solution in the skin of the flank. The injection site was examined for skin reaction after a period of 24 hours following challenge.

GLP compliance:

no

Type of study:

Draize test

Justification for non-LLNA method:

Currently no LLNA study is available for assessment. The Draize test has been carried out as an animal test to predict human sensitisation for over a decade and is recommended by international test guidelines.

Test material

Test material information

Constituent 1

Reference substance name:

Sodium N-(2-carboxyethyl)-N-dodecyl-β-alaninate

EC Number:

239-032-7

EC Name:

Sodium N-(2-carboxyethyl)-N-dodecyl-β-alaninate

Cas Number:

14960-06-6

Molecular formula:

C18H35NO4.Na

IUPAC Name:

sodium 3-[(2-carboxyethyl)(dodecyl)amino]propanoate

In vivo test system

Test animals

Species:

guinea pig

Strain:

not specified

Sex:

male

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: not specified
- Weight at study initiation: 350 - 450 g
- No further details given

Study design: in vivo (non-LLNA)

Induction

Route:

intradermal

Vehicle:

physiological saline

Concentration / amount:

0.1%

Day(s)/duration:

daily injections for a period of 20 days

Challenge

Route:

intradermal

Vehicle:

physiological saline

Concentration / amount:

0.15%

Day(s)/duration:

2 weeks after last induction injection / single injection

No. of animals per dose:

10

Details on study design:

A. INDUCTION EXPOSURE
- No. of exposures: 10
- Exposure period: 20 days
- Site: depilated skin region below the midline of the back
- Frequency of applications: injection was done every other day
- Concentrations: 0.1% test item solution
- Injected volume: 0.1 mL, except for the first injection (0.05 mL)
- Reading: skin readings were made at the injection sites, 24 hours after each injection had been done; the skin was examined for diameter, heigh and colour.

B. CHALLENGE EXPOSURE
- No. of exposures: one
- Challenge: done after 2 weeks following the last induction injection
- Site: skin of the flank.
- Concentrations: 0.1% test item solution
- Injected volume: 0.05 mL
- Evaluation (hr after challenge): 24 hours

READING
The application site was examined for diameter, heigh and colour. The readings were compared with those made at the sites of the first injection series (induction). If the reactions after challenge were appreciably more pronounced than those observed during induction, the test item was defined as a sensitizer. The degree of sensitization was considered to be, in part, proportional to the observed increase in skin reaction.

Results and discussion

In vivo (non-LLNA)

Results

Key result

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

0.1%

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

Skin reaction at induction was characterized by a mean diameter of 3.6 mm, a mean height of < 1 mm, and a pink coloration (indicates slight erythema). Reaction after challenge had a mean diameter of 3.5 mm, a mean height of < 1mm, and a pink coloration.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met