3,5,5-trimethylhexanal

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

July 1996 - July 1997

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1997

Report date:

1997

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:

3,5,5-trimethylhexanal

EC Number:

226-603-0

EC Name:

3,5,5-trimethylhexanal

Cas Number:

5435-64-3

Molecular formula:

C9H18O

IUPAC Name:

3,5,5-trimethylhexanal

Details on test material:

klare, farblose Flüssigkeit
Flüssigkeit erscheint optisch homogen
ph-Wert nicht messbar
Haltbarkeit > 1 Jahr
Reinheit 97% (1H- und 13C-NMR-Spektroskopie)

Test animals

Species:

rabbit

Strain:

Himalayan

Remarks:

Mol: Russian/Chbb: HM

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Mollegaard Breeding /Research Centre Ltd., Skensved, Denmark
- Age at study initiation: adult
- Weight at study initiation: 2,4 - 2,6 kg
- Housing: conventional, single-housed
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: at least 14 days
- sex: male

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 +/- 3 ° C
- Humidity (%): 30 - 70 %
- Air changes (per hr): 15-fold per hr
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: From: 22.07.1996 To:13.08.1996

Test system

Type of coverage:

semiocclusive

Preparation of test site:

shaved

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

0,5 cm³ of the test item were applied on 6 cm² skin

Duration of treatment / exposure:

4 h

Observation period:

The evaluation is performed 30-60 minutes, 24 h, 48 h und 72 h,
6, 8, 10, 17 and 21 days after patch removal.

Number of animals:

3

Details on study design:

The rabbits were examined for their general state of health about 24 h before application of the test substance. In the dorsal region the animals were sheared with a small chopper with a cutting height of 1/2 mm.

For the test, three test animals per 0.5 cm³ of the liquid test substance were applied to a skin area of approximately 6 cm.sup.2 and treated with a
coverage . Subsequently, this area was covered with a non-irritating patch and with a semiocculsive bandage
for four hours. After expiry of the exposure time, the dressing was removed and the application area was washed with warm water.

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

edema score

Basis:

mean

Time point:

24/48/72 h

Score:

ca. 3.67

Max. score:

4

Reversibility:

fully reversible

Results 2

Irritation parameter:

edema score

Basis:

animal #3

Time point:

24/48/72 h

Score:

4

Max. score:

4

Reversibility:

fully reversible within: 14d

Results 3

Irritation parameter:

edema score

Basis:

animal #2

Time point:

24/48/72 h

Score:

3

Max. score:

4

Reversibility:

fully reversible within: 14d

Results 4

Irritation parameter:

edema score

Basis:

animal #1

Time point:

24/48/72 h

Score:

4

Max. score:

4

Reversibility:

fully reversible within: 14d

Results 5

Irritation parameter:

erythema score

Basis:

mean

Time point:

24/48/72 h

Score:

ca. 3.78

Max. score:

4

Reversibility:

fully reversible

Results 6

Irritation parameter:

erythema score

Basis:

animal #3

Time point:

24/48/72 h

Score:

4

Max. score:

4

Reversibility:

fully reversible within: 14d

Results 7

Irritation parameter:

erythema score

Basis:

animal #2

Time point:

24/48/72 h

Score:

3.33

Max. score:

4

Reversibility:

fully reversible within: 14d

Results 8

Irritation parameter:

erythema score

Basis:

animal #1

Time point:

24/48/72 h

Score:

4

Max. score:

4

Reversibility:

fully reversible within: 14d

Irritant / corrosive response data:

see excecutive summary

Applicant's summary and conclusion

Interpretation of results:

Category 2 (irritant) based on GHS criteria

Remarks:

Criteria used for interpretation of results: EU

Conclusions:

3,5,5-trimethylhexanal has to be classified as skin irritant according to CLP Regulation (EC) No. 1272/2008

Executive summary:

The test for acute skin irritation in the rabbit with TRIMETHYLHEXANAL was performed on three animals with an exposure time of 4 hours. The liquid test substance was applied undiluted once to the sheared intact skin.

The administration of the test substance led to severe erythema and oedemas associated with hypodermic hemorrhage 24 h after patch removal in all three animals on the skin. 48 h after patch removal, the skin irritation in two animals remained unchanged.

The surface of the skin was dry. The third animal showed a moderate to severe erythema associated with a slight edema (edges of the application area were clearly defined by the swelling). The skin in the application area was yellowish-colored. After 72 h, the skin irritation in two animals remained unchanged. At the time, a hardening of the skin surface was observed at the time of the appearance of the skin dryness. The third animal exhibited moderate to severe erythema and moderate edema. The skin was still yellowish discolored. 6 days after patch removal, erythema and edema formation on the skin remained strong. The skin in the application area was brownish discolored and hardened. The formed scaly plate was cracked in two animals. On the 8th day of the experiment, an erythema was clearly observed in one animal, and a moderate to severe erythema was observed in two animals. The skin was moderately swollen (about 1 mm thick) in all three animals. The scaly plates on the skin were cracked and in an animal already in detachment. On the tenth day erythema formation was still clear. The animals showed a slight edema of the treated skin. The cracked dandruff plate was in two animals in detachment.

No erythema and edema formation on the skin was observed on observation days 14, 17 and 21. The skin irritations healed completely with the formation of scales, which gradually separated. One animal showed a red shining skin under the detached scales. On the 21st day of the experiment, the skin of the animals was not found. The hair had grown in the application area.