Dodecane-12-lactam

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1989-04-11 - 1989-05-05

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: No positive control (not required by 1981 version of Test Guideline)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1989

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

Version / remarks:

1981

Deviations:

no

GLP compliance:

no

Type of study:

guinea pig maximisation test

Justification for non-LLNA method:

A skin sensitization test according to OECD 406 has already excisted since 1989 and is sufficient for evaluation of the skin sensitisation potential of the test substance.

Test material

Test material information

Constituent 1

Reference substance name:

Dodecane-12-lactam

EC Number:

213-424-8

EC Name:

Dodecane-12-lactam

Cas Number:

947-04-6

Molecular formula:

C12H23NO

IUPAC Name:

1-azacyclotridecan-2-one

Test material form:

solid

Details on test material:

Dodecane-12-lactam of Hüls AG, purity approx. 99.9 %; main impurity cyclododecanone approx. 100 ppm

In vivo test system

Test animals

Species:

guinea pig

Strain:

Dunkin-Hartley

Sex:

male

Details on test animals and environmental conditions:

- Strain: Dunkin-Hartley (Bor: DHPW)
- Source: F. Winkelmann, Borchen
- Weight at study initiation: test group mean 325 g; control group mean 324 g
- Environmental conditions:
feed: G4 diet for guinea pigs (Ssniff; Soest, Germany);
water: tap water ad libitum;
room temperature: 20°C (+/- 1°C);
humidity: 60% (+/- 5%);
air change: 15 times/hour;
light-dark rhythm: 12 hours light/dark

Study design: in vivo (non-LLNA)

Induction

Induction 1

Route:

intradermal and epicutaneous

Vehicle:

corn oil

Induction 2

Concentration / amount:

1st application: Induction 1 % intracutaneous
2nd application: Induction 25 % occlusive epicutaneous
3rd application: Challenge 25 % occlusive epicutaneous

Challenge

Challenge 1

Route:

epicutaneous, occlusive

Vehicle:

corn oil

Challenge 2

Concentration / amount:

1st application: Induction 1 % intracutaneous
2nd application: Induction 25 % occlusive epicutaneous
3rd application: Challenge 25 % occlusive epicutaneous

No. of animals per dose:

20 (test) / 9 (control)

Details on study design:

ADMINISTRATION/EXPOSURE
- Preparation of test substance for induction: The test substance was ground to a fine powder and dissolved in the vehicle (corn oil) at elevated temperature. After cooling down, the resulting suspension was thoroughly mixed.
- Induction schedule: single intracutaneous treatment, 1 week later dermal induction; slight to medium inflammation caused (10 % SDS in vaseline) before application of patch; patch removed after 48 h
- Challenge schedule: after 2 further weeks, occlusive epicutaneous, removal of patch after 24 h, readings after further 24 and 48 hours.
EXAMINATIONS
- Grading system:
0 % of animals positive: no sensitisation
1 - 8 % of animals positive: very slight sensitisation
9 - 28 % of animals positive: slight sensitisation
29 - 64 % of animals positive: distinct sensitisation
65 - 80 % of animals positive: severe sensitisation
81 -100 % of animals positive: extreme sensitisation

Challenge controls:

Treatment: vehicle

Positive control substance(s):

not required

Remarks:

not required by 1981 version of Test Guideline

Results and discussion

Positive control results:

not applicable

In vivo (non-LLNA)

Results

Results 1

Key result

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

25% preparation of test item in corn oil

No. with + reactions:

0

Total no. in group:

20

Clinical observations:

see overall remarks (below)

Remarks on result:

other: Reading: 1st reading. . Hours after challenge: 24.0. Group: test group. Dose level: 25% preparation of test item in corn oil. No with. + reactions: 0.0. Total no. in groups: 20.0. Clinical observations: see overall remarks (below).

Results 2

Key result

Reading:

2nd reading

Hours after challenge:

48

Group:

test chemical

Dose level:

25% preparation of test item in corn oil

No. with + reactions:

0

Total no. in group:

20

Clinical observations:

see overall remarks (below)

Remarks on result:

other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: test group. Dose level: 25% preparation of test item in corn oil. No with. + reactions: 0.0. Total no. in groups: 20.0. Clinical observations: see overall remarks (below).

Applicant's summary and conclusion

Conclusions:

Under the conditions of this guinea pig maximization test, the test item lauryl lactame showed no dermal sensitization in male guinea pigs.

Executive summary:

In a guinea pig maximization test performed with the test item lauryl lactame, after intracutane and epidermal inductions and 24 hours as well as 48 hours after epidermal challenge none of the 20 animals examined in this study, showed positive response regarding dermal sensitization.

Under the conditions of this guinea pig maximization test, the test item lauryl lactame showed no dermal sensitization in male guinea pigs.