2,4,6-trimethylbenzaldehyde

Endpoint summary

Description of key information

Under the test conditions (OECD 404) the test substance is considered to be irritating to the skin.

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records

Reference

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:

other: Guideline study, available as unpublished report, minor restrictions, fully adequate for assessment

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Deviations:

yes

Remarks:

, occlusive conditions used

GLP compliance:

not specified

Species:

rabbit

Strain:

other: Japanese White rabbits K bL:JW (SPF)

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Kitayama Labes Co., Ltd.
- Age at study initiation: ca. 10 weeks
- Weight at study initiation: 2.2-2.4 kg
- Housing: individually housed in suspended metallic cages on a Z-type rabbit cage rack washable with water (ZR-18U, Natsume Seisakusho Co., Ltd.).
- Diet: Pellet food for rabbits RC-4 (Oriental Yeast Co., Ltd.), ad libitum.
- Water: Tap water, ad libitum.
- Acclimation period: 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 2
- Humidity (%): 55 ± 6
- Photoperiod (hrs dark / hrs light):12/12

Type of coverage:

occlusive

Preparation of test site:

clipped

Vehicle:

unchanged (no vehicle)

Controls:

not required

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 5 mL on a circle of about 6 cm2

Duration of treatment / exposure:

4 hours

Observation period:

7 days

Number of animals:

3

Details on study design:

TEST SITE
- Area of exposure: 6cm2
- Type of wrap if used: double-layer gauze and occlusively secured with Tegaderm (3M) and Tubicot No. 5 (Alcare Co., Ltd.)

REMOVAL OF TEST SUBSTANCE
- Washing (if done): Applied areas were wiped with gauze moistened with water.
- Time after start of exposure: 4 hours

Irritation parameter:

erythema score

Basis:

animal #1

Time point:

other: mean 24, 48, and 72 hours

Score:

2.7

Max. score:

4

Reversibility:

fully reversible within: 6 days

Irritation parameter:

erythema score

Basis:

other: #2, #3

Time point:

other: mean 24, 48, and 72 hours

Score:

2.3

Max. score:

4

Reversibility:

fully reversible within: 6 days

Irritation parameter:

edema score

Basis:

animal: #1, #2, #3

Time point:

other: mean 24, 48, and 72 hours

Score:

1.7

Max. score:

4

Reversibility:

fully reversible within: 6 days

Irritant / corrosive response data:

Two rabbits showed well-defined erythema (score 2) 30-60 min after 4-hr exposure. One rabbit showed very slight (barely perceptible) erythema (score 1), while another showed very slight (barely perceptible) edema (score 1). At 24 and 48 hrs after exposure, all three rabbits showed intensified dermal changes with well defined or moderate to severe erythema (score 3) and slight edema (score 2). A tendency toward recovery was noted thereafter, with all three rabbits showing a recovery with scale-like changes by 7 days after termination of exposure.

Interpretation of results:

irritating

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Under the test conditions (OECD 404) the test substance is considered to be irritating to the skin.

Executive summary:

According to OECD guideline 404, a primary skin irritation study was conducted. The test substance was topically applied to the back skin (circular area of about 6 cm2) of 3 Japanese white rabbits for 4 hours under occlusive conditions. Two rabbits showed well-defined erythema (score 2) 30-60 min after exposure. One rabbit showed very slight (barely perceptible) erythema (score 1), while another showed very slight (barely perceptible) edema (score 1). At 24 and 48 hours after exposure, all three rabbits showed intensified dermal changes with well defined or moderate to severe erythema (score 3) and slight edema (score 2). A tendency toward recovery was noted thereafter, with all three rabbits showing a recovery with scale-like changes by 7 days after termination of exposure. Under the test conditions (OECD 404) the test substance is considered to be irritating to the skin.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (irritating)

Eye irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

According to OECD guideline 404, a primary skin irritation study was conducted. The test substance was topically applied to the back skin (circular area of about 6 cm2) of 3 Japanese white rabbits for 4 hours under occlusive conditions. Two rabbits showed well-defined erythema (score 2) 30-60 min after exposure. One rabbit showed very slight (barely perceptible) erythema (score 1), while another showed very slight (barely perceptible) edema (score 1). At 24 and 48 hours after exposure, all three rabbits showed intensified dermal changes with well defined or moderate to severe erythema (score 3) and slight edema (score 2). A tendency toward recovery was noted thereafter, with all three rabbits showing a recovery with scale-like changes by 7 days after termination of exposure. Under the test conditions (OECD 404) the test substance is considered to be irritating to the skin.

Justification for selection of skin irritation / corrosion endpoint:
OECD guideline study, available as unpublished report, minor restrictions, fully adequate for assessment

Effects on skin irritation/corrosion: irritating

Justification for classification or non-classification

Based on the skin irritation study, the substance has to be classified as Skin Irrit 2: H315: Causes skin irritation according to the EU Classification, Labelling and Packaging of Substances and Mixtures (CLP) Regulation (EC) No. 1272/2008 and as Xi:R38: Irritating to skin according to Directive 67/548/EEC.

In the absence of an eye irritation study, the justification for classification is based on the skin irritation study. Therefore, the substance is classified as Eye Irrit 2: H319: Causes serious eye irritation according to the EU Classification, Labelling and Packaging of Substances and Mixtures (CLP) Regulation (EC) No. 1272/2008 and as Xi:R36: Irritating to eyes according to Directive 67/548/EEC.