Registration Dossier

Toxicological information

Skin sensitisation

Currently viewing:

Administrative data

Endpoint:
skin sensitisation: in vivo (non-LLNA)
Type of information:
migrated information: read-across based on grouping of substances (category approach)
Adequacy of study:
key study
Study period:
1992-01-13 to 1992-02-21
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: This study is classified as reliable without restrictions because it closely followed OECD 406 guidelines, the Buehler method is a preferred method under OPPTS harmonized guidelines, and the study was GLP compliant.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1992

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 406 (Skin Sensitisation)
Deviations:
no
GLP compliance:
yes
Type of study:
Buehler test

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): Neodene 18 Alpha Olefin
- Substance type: C18 alpha olefin
- Physical state: Clear colourless liquid

In vivo test system

Test animals

Species:
guinea pig
Strain:
Hartley
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Weight at study initiation: 299 to 511 grams
- Housing: Housed singly
- Diet (e.g. ad libitum): Ad libitum
- Water (e.g. ad libitum): Ad libitum
- Acclimation period: 4 days

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


Study design: in vivo (non-LLNA)

Inductionopen allclose all
Route:
epicutaneous, occlusive
Vehicle:
other: Acetone
Concentration / amount:
Irritation Screening: 50, 25, 10, 5, 2.5, 1, 0.5 % W/V in acetone
Induction Phase: 5 % W/V in acetone
Challenge Phase: 2.5 % in both test and naive control group; W/V in acetone
Challengeopen allclose all
Route:
epicutaneous, occlusive
Vehicle:
other: Acetone
Concentration / amount:
Irritation Screening: 50, 25, 10, 5, 2.5, 1, 0.5 % W/V in acetone
Induction Phase: 5 % W/V in acetone
Challenge Phase: 2.5 % in both test and naive control group; W/V in acetone
No. of animals per dose:
Irritation Screening: 4 males and 4 females
Induction Phase: 10 males and 10 females
Challenge Phase: In addition to 20 test animals (10 M; 10 F), 5 male and 5 female naive controls used
Details on study design:
RANGE FINDING TESTS:
A preliminary irritation phase was conducted to determine the appropriate level of Neodene 18 alpha olefin that should be used in the main study. The primary irritation was conducted using 50, 25, 10, 5, 2.5, 1, and 0.5 % of the test material W/V in acetone.

MAIN STUDY
A. INDUCTION EXPOSURE
- No. of exposures: Three
- Exposure period: 6 hours
- Test groups: 10 males; 10 females
- Site: Animal backs
- Frequency of applications: Once a week
- Duration: Three weeks
- Concentrations: 5 % W/V in acetone

B. CHALLENGE EXPOSURE
- No. of exposures: One
- Day(s) of challenge: One
- Exposure period: 6 hours
- Test groups: 10 Males; 10 females
- Control group: 5 males; 5 females
- Site: Animal backs
- Concentrations: 2.5 % W/V in acetone
- Evaluation (hr after challenge): 24 and 48 hours


Challenge controls:
Five male and five female naive control animals were used during the challenge exposure.
Positive control substance(s):
no
Remarks:
A positive control group was not used in this study.

Study design: in vivo (LLNA)

Statistics:
Use of statistical methods for data analyses is not reported in the study.

Results and discussion

Positive control results:
Not applicable since a positive control group was not used in the study.

In vivo (non-LLNA)

Resultsopen allclose all
Reading:
1st reading
Hours after challenge:
24
Group:
test group
Dose level:
2.5 % W/V in acetone
No. with + reactions:
7
Total no. in group:
19
Clinical observations:
None reported; one animal was found dead at the 24 hour observation; sensitisation reactions were slight, patchy erythema and scored as +/-
Remarks on result:
other: see Remark
Remarks:
Reading: 1st reading. . Hours after challenge: 24.0. Group: test group. Dose level: 2.5 % W/V in acetone. No with. + reactions: 7.0. Total no. in groups: 19.0. Clinical observations: None reported; one animal was found dead at the 24 hour observation; sensitisation reactions were slight, patchy erythema and scored as +/-.
Reading:
2nd reading
Hours after challenge:
48
Group:
test group
Dose level:
2.5 % W/V in acetone
No. with + reactions:
6
Total no. in group:
19
Clinical observations:
None reported; sensitisation reactions were slight, patchy erythema and scored as +/-
Remarks on result:
other: see Remark
Remarks:
Reading: 2nd reading. . Hours after challenge: 48.0. Group: test group. Dose level: 2.5 % W/V in acetone. No with. + reactions: 6.0. Total no. in groups: 19.0. Clinical observations: None reported; sensitisation reactions were slight, patchy erythema and scored as +/-.
Reading:
1st reading
Hours after challenge:
24
Group:
negative control
Dose level:
2.5 % W/V acetone
No. with + reactions:
5
Total no. in group:
10
Clinical observations:
None reported; sensitisation reactions were slight, patchy erythema and scored as +/-
Remarks on result:
other: see Remark
Remarks:
Reading: 1st reading. . Hours after challenge: 24.0. Group: negative control. Dose level: 2.5 % W/V acetone. No with. + reactions: 5.0. Total no. in groups: 10.0. Clinical observations: None reported; sensitisation reactions were slight, patchy erythema and scored as +/-.
Reading:
2nd reading
Hours after challenge:
48
Group:
negative control
Dose level:
2.5 % W/V in acetone
No. with + reactions:
6
Total no. in group:
9
Clinical observations:
None reported; one animal was found dead at the 48 hour observation; sensitisation reactions were slight, patchy erythema and scored as +/-
Remarks on result:
other: see Remark
Remarks:
Reading: 2nd reading. . Hours after challenge: 48.0. Group: negative control. Dose level: 2.5 % W/V in acetone. No with. + reactions: 6.0. Total no. in groups: 9.0. Clinical observations: None reported; one animal was found dead at the 48 hour observation; sensitisation reactions were slight, patchy erythema and scored as +/-.

Applicant's summary and conclusion

Interpretation of results:
not sensitising
Remarks:
Migrated information
Conclusions:
The study authors reported that following the primary challenge at a concentration of 2.5%, there were no grades of 1 produced in the test or control animals. The incidence of grade +/- responses in the test group (total 10 animals out of 19) was compared to the naïve control group (6 out of 10; one animal dead at the 48 hours observation period). Based on these results, the authors concluded that the incidence and severity of these responses in the test group were essentially comparable to those produced by the naïve control group indicating that sensitization had not been induced.
Executive summary:

In a skin sensitisation study, 10 male and female Hartley albino guinea pigs were treated with Neodene-18 alpha olefin to determine its skin sensitisation potential using the Buehler Technique.

 

The study authors reported that following the primary challenge at a concentration of 2.5%, there were no grades of 1 produced in the test or control animals. The incidence of grade+(numerical values of 0.5) responses in the test group (total 10 animals out of 19) was compared to the naïve control group (6 out of 10; one animal dead at the 48 hours observation period). Based on these results, the authors concluded that the incidence and severity of these responses in the test group were essentially comparable to those produced by the naïve control group indicating that sensitization had not been induced.

 

This study received a Klimisch rating of reliable without restrictions because it closely followed OECD 406 guidelines. The Buehler method is a preferred method under OPPTS harmonized guidelines, and the study was GLP compliant.