2-Butanone, peroxide

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study without detailed documentation

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1984

Report date:

1984

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: EEC Directive 79/831, Annex V, Part B: Methods for the determination of toxicity, B.4. Acute toxicity, skin irritation

Deviations:

no

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

2-[(2-hydroperoxybutan-2-yl)peroxy]butane-2-peroxol; butane-2,2-diperoxol

EC Number:

700-954-4

Cas Number:

1338-23-4

Molecular formula:

Mixture of C4H10O4 and C8H18O6

IUPAC Name:

2-[(2-hydroperoxybutan-2-yl)peroxy]butane-2-peroxol; butane-2,2-diperoxol

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Age at study initiation: adult and healthy

Test system

Type of coverage:

occlusive

Preparation of test site:

abraded

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

TEST MATERIAL
- Concentration : 0.5 mL

Duration of treatment / exposure:

24 hours

Observation period:

24 hours and 48 hours

Number of animals:

12 animals

Details on study design:

- Six animals are treated on the intact, the other six animals on the abraded skin.
- Primary irritation to the skin is measured by a patch-test technique on the abraded and intact skin of albino rabbits.
- An amount of 0.5 mL of 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 maitain the test patches in position and to retard evaporation of substances.
- 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. 82 (1944) 377 - 390). A second reading is made 48 hours later (72 hours after application).

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

mean

Time point:

24/48/72 h

Score:

4

Max. score:

4

Results 2

Irritation parameter:

edema score

Basis:

mean

Time point:

24/48/72 h

Score:

1.8

Max. score:

4

Irritant / corrosive response data:

The dermal effects observed at the end of the 4-hour exposure period were well-defined erythema, slight to moderate ischemia, slight to moderate haemorrhages and severe oedema.

Other effects:

After one week: moderate scaliness to severe incrustation.
After two weeks the old necrotic skin had been ejected.
After eight weeks scar tissue and slightly disturbed hair growth were observed on the application sites.

Any other information on results incl. tables

Individual and average skin irritation scores of methyl-ethylketone peroxide:

 

Rabbit number	Hours after patch removed
	1 hours		24 hours		48 hours		72 hours
	A	B	A	B	A	B	A	B
2059	4	4	4	2	4	2	4	1
2060	4	4	4	2	4	1	4	1
2061	4	4	4	3	4	1	4	1
2062	4	4	4	3	4	1	4	1
2063	4	4	4	3	4	2	4	2
2064	4	4	4	3	4	2	4	2
average	8.0		6.7		5.5		5.3

 

A = erythema

B = oedema

Applicant's summary and conclusion

Interpretation of results:

Category 1B (corrosive) based on GHS criteria

Conclusions:

On the basis of the present results, it can be concluded that undiluted methyl-ethylketone peroxide in DMP is corrosive with the skin, under occlusion, for four hours, as scar formation and permanent skin damage was observed.

Executive summary:

Methyl-ethylketone peroxide in DMP was tested in irritation study to skin according to the EEC Directive 79/831, Annex V, Part B, B.4 Acute toxicity, skin irritation. Primary irritation to the skin is measured by patch-test technique on the abraded and intact skin of albino rabbits.

An amount of 0.5 mL of the test substance is brought on the intact or abraded skin under a surgical patch measuring 1 inch x 1 inch. Six rabbits are treated on the intact skin, the other six on the abraded skin. 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. A second reading is made 72 hours after application. The dermal effects observed at the end of the 4 -hour exposure period considered of well-defined erythema, slight to moderate ischemia, slight to moderate haemorrhages and severe oedema. After one week all application sites generally showed moderate to severe incrustation. After two weeks the old necrotic skin had been ejected. The new skin on the application sites showed moderate scaliness, decreased hair growth and some signs of scar tissue formation. After eight weeks scar tissue and slightly disturbed hair growth were observed on the application sites.

Based on these results, it can be concluded that undiluted methyl-ethylketone peroxide is corrosive to the skin under occlusive test conditions for four hours.