1,1,3,3-tetramethylbutyl hydroperoxide

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

June, 1977

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Well-conducted study done according to guideline in force at the time. Documentation is sufficient but not extensive, also as was practice when the study was done. Study was performed prior to GLP regulations.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1978

Report date:

1978

Materials and methods

Test guideline

Test guideline 1

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Deviations:

yes

Remarks:

Application time was 24 hours instead of four.

Test guideline 2

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.2500 (Acute Dermal Irritation)

Deviations:

no

Remarks:

Application time was 24 hours which is permitted in this guideline.

GLP compliance:

no

Remarks:

Study was performed prior to GLP regulations.

Test material

Test material information

Constituent 1

Reference substance name:

Test material described as "TMPH, chemical name: 2,4,4-trimethylpentyl-2-hydroperoxide"

IUPAC Name:

Test material described as "TMPH, chemical name: 2,4,4-trimethylpentyl-2-hydroperoxide"

Test material form:

other: clear, colourless liquid

Details on test material:

None

Test animals

Species:

rabbit

Strain:

New Zealand White

Test system

Type of coverage:

occlusive

Preparation of test site:

other: Six rabbits treated on intact skin, six on abraded skin.

Vehicle:

unchanged (no vehicle)

Controls:

not required

Amount / concentration applied:

0.5 ml

Duration of treatment / exposure:

24 hours

Observation period:

72 hours after application

Number of animals:

Twelve (six intact skin, six abraded skin)

Details on study design:

Primary irritation to the skin is measured by a patch-test technique on the abraded and intact skin of albino rabbits.

Twelve healthy adult New Zealand White albino rabbits are used for 1-4 test substances. Twenty four hours prior to applying the materials, the hair is removed from the backs of the animals with an electric clipper in such a way as to avoid abrasions.

An amount of 0.5 ml (in case of liquids) or 0.5 g (in case of solids or semi-solids) of the test substance is brought on the intact or abraded skin under a surgical patch measuring 1 inch x 1 inch. The patches are fixed to the application site by means of adhesive tape and the entire trunk of the rabbits is wrapped with an impervious material to maintain the test patches in position and to retard evaporation of volatile substances.

Six rabbits are treated on the intact skin, the other six on the abraded skin. The abrasions are minor incisions through the stratum corneum, but not sufficiently deep to disturb the derma or to produce bleeding.

After an exposure period of 24 hours the patches and the material applied are removed and the resulting skin reactions are evaluated by the method of Draize (J. Pharmacol 84 (1944) 377-390). A second reading is made 48 hours later (72 hours after application).

Results and discussion

In vivo

Results

Irritation parameter:

overall irritation score

Basis:

mean

Time point:

other: 24 hours

Score:

6.8

Max. score:

7

Reversibility:

not fully reversible within: 72 hours

Remarks on result:

other: see table below

Remarks:

see table below

Irritant / corrosive response data:

The individual and average skin irritation scores are presented in the table below. Generally, the dermal effect of TMPH after 24 hours was distinct ischemia and slight or moderate edema.

Other effects:

None recorded.

Any other information on results incl. tables

sa

Rabbit number	Intact skin 24 hours	Intact skin 72 hours	Rabbit number	Abraded skin 24 hours	Abraded skin 72 hours
	erythema - edema			erythema - edema
6609	4 - 2	4	6603	4 - 3	4
6610	4 - 3	4	6604	4 - 3	3
6611	4 - 3	4	6605	4 - 3	4
6612	4 - 3	4	6606	4 - 3	4
6613	4 - 3	4	6607	4 - 3	4
6614	4 - 3	4	6608	4 - 2	4
average	6.8	4.0		6.8	3.8

Applicant's summary and conclusion

Interpretation of results:

Category 1B (corrosive) based on GHS criteria

Remarks:

Migrated information Criteria used for interpretation of results: other: Draize

Conclusions:

The following degree of skin irritation was observed. TMPH: very severe.

Executive summary:

Primary irritation to the skin is measured by a patch-test technique on the abraded and intact skin of albino rabbits.

Six rabbits are treated on the intact skin, the other six on the abraded skin. The abrasions are minor incisions through the stratum corneum, but not sufficiently deep to disturb the derma or to produce bleeding.

After an exposure period of 24 hours the patches and the material applied are removed and the resulting skin reactions are evaluated by the method of Draize (J. Pharmacol 84 (1944) 377-390). A second reading is made 48 hours later (72 hours after application).

The following degree of skin irritation was observed. TMPH: very severe. Generally, the dermal effect of TMPH after 24 hours was distinct ischemia and slight or moderate edema.