Di-tert-butyl 3,3,5-trimethylcyclohexylidene diperoxide

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

3 Days

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Well documented study according to OECD 404 and OECD & French Government GLP. Study report includes, QA & GLP statement and C of A for test article.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1995

Report date:

1995

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

6731-36-8 (97.4%)

IUPAC Name:

6731-36-8 (97.4%)

Constituent 2

Reference substance name:

Di-tert-butyl 3,3,5-trimethylcyclohexylidene diperoxide

EC Number:

229-782-3

EC Name:

Di-tert-butyl 3,3,5-trimethylcyclohexylidene diperoxide

Cas Number:

6731-36-8

Molecular formula:

C17H34O4

IUPAC Name:

1,1-bis(tert-butylperoxy)-3,3,5-trimethylcyclohexane

Details on test material:

The test substance LUPEROX 231 (l,l-DI-(tert-BUTYLPEROXY)-3,3,5-TRIMETHYLCYCLOHEXANE) used in the study was supplied by Elf Atochem Deutschland. Documentation supplied by the Sponsor identified the test substance as follows:

-name: LUPEROX 231 (l,1-DI-(tert-BUTYLPEROXY)-3,3,5 TRIMETHYLCYCLOHEXANE)
- labelling: LUPEROX 231
-batch number: 530-9502-102
- protocol and labelling: 530-9502-102
-description: colourless to yellowish liquid,
-quantity and container: 2 plastic flasks each containing 0.1 kg
-date of receipt: 18.5.95
-storage conditions: at room temperature and protected from light
-purity: 97.4%.
Data relating to the characterization of the test substance are documented in a test article description and results of analysis provided by the Sponsor.
The pH of the test substance was not measurable.

Preparation
The test substance was applied in its original form.

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

Animals
-Sex, species, strain: male New Zealand White rabbits.
-Reason for this choice: species commonly requested by the international regulations for this type of study.
-Breeder: Elevage Cunicole de Val de Selle, 80160 Prouzel, France.
-Number of animals and identification: three animals were used, as recommended by the international regulations and taking into account that a good correlation of results can be obtained with either three or six animals. The animals were identified individually with a metal tag in the ear.
-Weight: on the day of treatment, the animals had a mean body weight ± standard deviation of 2.5 ± 0.2 kg.
-Acclimatization: at least five days before the beginning of the study.

Environmental conditions
During the acclimatization period and during the main test, the environmental conditions in the animal room were set as follows:
-temperature: 18 ± 3°C
-relative humidity: 30 to 70%
-light/dark cycle: 12 hl12 h
The temperature and relative humidity were recorded continuously and records retained.
The housing conditions (temperature, relative humidity and light/dark cycle) were checked
regularly.The animals were housed individually in polystyrene cages (35 cm x 55 cm x 32 cm or
48.2 cm x 58 cm x 36.5 cm). Each cage was equipped with a food container and a water bottle.

Food and water
All the animals had free access to 112 C pelleted diet (U.A.R., 91360 Villemoisson-sur-Orge, France). Each batch of food was analysed (composition and contaminants) by the supplier. Drinking water filtered by a F.G. Millipore membrane (0.22 micron) was provided ad libitum. Bacteriological and chemical analysis of the water and detection of possible contaminants (pesticides, heavy metals and nitrosamines) are performed periodically. Results ar archived at C.I.T. It was verified that no contaminants in the diet or water at levels likely to influence the outcome of the study were present.

Test system

Type of coverage:

semiocclusive

Preparation of test site:

other: unabraded

Vehicle:

unchanged (no vehicle)

Controls:

other: each animal served as its own control, untreated sites

Amount / concentration applied:

A single dose of 0.5 ml of the test substance was applied to a 6 cm2 dry gauze pad (Semes France, 54183 Heillecourt, France) which was then applied to the right (application for four hours) or the left flank (application for three minutes) of the animals. The test substance and the gauze pad were held in contact with the skin by means of an adhesive hypoallergenic aerated semi-occlusive dressing (Laboratoires de Pansements et d'Hygiene,
21300 Chenove, France) and a restraining bandage (Laboratoires 3M Sante, 92245 Malakoff, France). After removal of the dressing, any residual test substance was wiped off by means of a dry gauze pad

The untreated skin served as control.

.

Duration of treatment / exposure:

4 hours

Observation period:

three minutes, one hour, 24 hr, 48 hr, 72 hr

Number of animals:

three

Details on study design:

Preparation and selection of the animals
The day before treatment, the flanks of each animal were clipped using electric clippers. The skin of each animal was examined in order to use only
animals without any signs of cutaneous irritation. Animals showing signs of cutaneous irritation, cutaneous defects or pre-existing dermal injury
were not used.

Study design
The study design was established according to available information on the test substance and following the O.E.C.D. and E.C. guidelines. As possible irritant effects were anticipated, a first assay was conducted with one animal. The duration of exposure was three minutes on one flank and four
hours on the other flank. Since the test substance was not strongly irritant in this first assay, it was then applied for four hours in two other animals in second assay.

Application of the test substance
The test substance was used in its original form.
A single dose of 0.5 ml of the test substance was applied to a 6 cm2 dry gauze pad (Semes France, 54183 Heillecourt, France) which was then applied to the right (application for four hours) or the left flank (application for three minutes) of the animals. The test substance and the gauze pad were heldin contact with the skin by means of an adhesive hypoallergenic aerated semi-occlusive dressing (Laboratoires de Pansements et d'Hygiene, 21300 Chenove, France) and a restraining bandage (Laboratoires 3M Sante, 92245 Malakoff, France). After removal of the dressing, any residual test substance was wiped off by means of a dry gauze pad. The untreated skin served as control.

Results and discussion

In vivo

Results

Irritation parameter:

overall irritation score

Basis:

mean

Time point:

other: day 2

Score:

ca. 2

Max. score:

2

Reversibility:

fully reversible

Irritant / corrosive response data:

After three-minute exposure (one animal): Very slight or slight erythema (grade 1 or 2) was observed up to day 3; it was accompanied by slight oedema (grade 2) on day 2 only. Dryness of the skin was noted from days 4 to 7.

After four-hour exposure (four animals)
Very slight or slight erythema (grade 1 or 2) was observed up to day 3 (two animals) or 6. It was accompanied by slight or severe oedema (grade 2 or 4) for 24 hours in all animals. Mean scores over 24, 48 and 72 hours for individual animals were 1.3, 1.0 and 1.0 for erythema and 0.7 for oedema.

Under the conditions fo this test, the test substance LUPEROX 231 (l,I-DI-(tertBUTYLPEROXY)-3,3,5-TRIMETHYLCYCLOHEXANE) was considered non-irritant when administered by cutaneous route in rabbits.

Applicant's summary and conclusion

Interpretation of results:

not irritating

Remarks:

Migrated information While a classification of "not irritating" is appropriate under the governing EEC Directive (93/21, April 27, 1993), a four-hour occlusive exposure clearly resulted in short-term irritant response, including severe edema at the end of exposure in 2/3 of t Criteria used for interpretation of results: EU

Conclusions:

CONCLUSION
Under these experimental conditions, the test substance LUPEROX 231 (l,I-DI-(tertBUTYLPEROXY)- 3,3,5-TRIMETHYLCYCLOHEXANE) was considered non-irritant when administered by cutaneous route in rabbits.

Executive summary:

RESULTS

-After three-minute exposure (one animal): Very slight or slight erythema (grade 1 or 2) was observed up to day 3; it was accompanied by slight oedema (grade 2) on day 2 only. Dryness of the skin was noted from days 4 to 7.

-After four-hour exposure (four animals): Very slight or slight erythema (grade 1 or 2) was observed up to day 3 (two animals) or 6. It was accompanied by slight or severe oedema (grade 2 or 4) for 24 hours in all animals.

-Mean scores over 24, 48 and 72 hours for individual animal were 1.3, 1.0 and 1.0 for erythema and 0.7 for oedema.

CONCLUSION

Under these experimental conditions, the test substance LUPEROX 231 (l,1-DI-(tertBUTYLPEROXY)- 3,3,5-TRIMETHYLCYCLOHEXANE) was considered non-irritant when administered by cutaneous route in rabbits.