Reaction mass of N,N-dimethyldecan-1-amide and N,N-dimethyloctanamide

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-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 Buehler protocol which satisfies the citeria of toxic control act (40 CFR) and the OECD Guideline, GLP, well documented

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1990

Report date:

1990

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

Version / remarks:

Conducted to general conditions satisfying the OECD Guideline

GLP compliance:

yes

Type of study:

Buehler test

Justification for non-LLNA method:

Study is from before LLNA test guidelines. Besides, it is clearly demonstrated that irritants and surfactants are more likely to give rise to false positives in the LLNA. Consequently, in the evaluation of such substances for sensitizing properties the LLNA test is not an appropriate assay and would not represent an optimum use of test animals.

Test material

Test material information

Constituent 1

Reference substance name:

Decanamide, N,N-dimethyl-, mixt. with N,N-dimethyloctanamide

Cas Number:

67359-57-3

IUPAC Name:

Decanamide, N,N-dimethyl-, mixt. with N,N-dimethyloctanamide

Constituent 2

Reference substance name:

N,N-Dimethyldecan-1-amide, mixture with N,N-Dimethyloctanc-1-amide

IUPAC Name:

N,N-Dimethyldecan-1-amide, mixture with N,N-Dimethyloctanc-1-amide

Details on test material:

- Chemical name: Mixture of N,N-Dimethydecan-1-amide and N,N-Dimethyloctan-1-amide
- Physical state: liquid
- Storage condition of test material: roomtemperature

In vivo test system

Test animals

Species:

guinea pig

Strain:

Hartley

Sex:

male/female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: approved supplier
- Weight: 374-623g
- Housing: wire mesh suspension cages
- Diet (e.g. ad libitum): ad libitum, PURINA GUINEA PIG CHOW
- Water (e.g. ad libitum): ad libitum
- Acclimation period: at least four days


ENVIRONMENTAL CONDITIONS
- Photoperiod (hrs dark / hrs light): 12h each

Study design: in vivo (non-LLNA)

Induction

Induction 1

Route:

epicutaneous, occlusive

Vehicle:

other: 80/20 ethanol/dest water; acetone

Induction 2

Concentration / amount:

Pilot: 100% (without vehicle), 50%, 25%, 10%, 5%, 2.5%, 1%, 0.5% (partly in 80/20 ethanol/dest water)
Main study Induction: 5% (in 80/20 ethanol/dest water)
Challenge: 2.5% (in acetone)

Challenge

Challenge 1

Route:

epicutaneous, occlusive

Vehicle:

other: 80/20 ethanol/dest water; acetone

Challenge 2

Concentration / amount:

Pilot: 100% (without vehicle), 50%, 25%, 10%, 5%, 2.5%, 1%, 0.5% (partly in 80/20 ethanol/dest water)
Main study Induction: 5% (in 80/20 ethanol/dest water)
Challenge: 2.5% (in acetone)

No. of animals per dose:

Main study test group: 10 males and 10 females
Main study control group: 5 males and 5 females

Details on study design:

RANGE FINDING TESTS:
Primary irritation 8 male and 8 female animals were used.

MAIN STUDY
A. INDUCTION EXPOSURE
- No. of exposures: 3
- Exposure period: 6h
- Frequency of applications: once a week
- Concentrations: 5%

B. CHALLENGE EXPOSURE
- No. of exposures: 1
- Day(s) of challenge: two weeks after last induction exposure
- Exposure period: 6h
- Test groups: 10 animals per gender
- Control group: 5 animals per gender
- Concentrations: 2.5%
- Evaluation (hr after challenge): 24hr

Challenge controls:

5 animals per gender were used as control, no positive control is reported

Positive control substance(s):

no

Results and discussion

In vivo (non-LLNA)

Results

Results 1

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

2.5%

No. with + reactions:

0

Total no. in group:

20

Remarks on result:

other: Reading: 1st reading. . Hours after challenge: 24.0. Group: test group. Dose level: 2.5%. No with. + reactions: 0.0. Total no. in groups: 20.0.

Results 2

Reading:

2nd reading

Hours after challenge:

48

Group:

test chemical

Dose level:

2.5%

No. with + reactions:

0

Total no. in group:

20

Remarks on result:

other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: test group. Dose level: 2.5%. No with. + reactions: 0.0. Total no. in groups: 20.0.

Results 3

Reading:

1st reading

Hours after challenge:

24

Group:

negative control

Dose level:

2.5%

No. with + reactions:

0

Total no. in group:

10

Remarks on result:

other: Reading: 1st reading. . Hours after challenge: 24.0. Group: negative control. Dose level: 2.5%. No with. + reactions: 0.0. Total no. in groups: 10.0.

Results 4

Reading:

2nd reading

Hours after challenge:

48

Group:

negative control

Dose level:

2.5%

No. with + reactions:

0

Total no. in group:

10

Remarks on result:

other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: negative control. Dose level: 2.5%. No with. + reactions: 0.0. Total no. in groups: 10.0.

Applicant's summary and conclusion

Interpretation of results:

not sensitising

Remarks:

Migrated information

Conclusions:

Only grade ± reactions comparable to the controls were observed. The test substance is considered to be not skin sensitising.

Executive summary:

The potential of the registered substance, as a 5% w/v formulation in 80% ethanol/20% distilled water, to produce delayed contact hypersensitivity in guinea pigs was evaluated using an adaptation of the method of Ritz and Buehler*.

Following primary challenge, there were no grades of 1 produced in the test or control animals. The incidence of grade + responses in the test group (14 of 20) was compared to that of the naive control group (7 of 10). The incidence and severity of these responses in the test group were essentially comparable to those produced by the naive control group indicating that sensitization had not been induced.