2(3H)-Benzofuranone, 5,7-bis(1,1-dimethylethyl)-3-(4-hydroxy-3,5-

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

21.06. - 04.09.1999

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: OECD guideline study, GLP.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1999

Report date:

1999

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Version / remarks:

adopted 1992

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.4 (Acute Toxicity: Dermal Irritation / Corrosion)

GLP compliance:

yes

Remarks:

NOTOX B.V., Hambakenwetering 7, 5231 DD ‘s-Hertogenbosch, The Netherlands

Test material

Test material information

Constituent 1

Reference substance name:

-

EC Number:

431-770-1

EC Name:

-

Cas Number:

216698-07-6

Molecular formula:

C32 H44 O4

IUPAC Name:

2-(2-oxo-5-(1,1,3,3-tetramethylbutyl)-2,3-dihydro-1-benzofuran-3-yl)-4-(1,1,3,3-tetramethylbutyl)phenyl acetate

Details on test material:

- Physical state: White solid
- Analytical purity: 98.7%
- Stability under test conditions: stable
- Storage condition of test material: At room temperature in the dark

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Nederland, The Netherlands.
- Age at study initiation: at least 6 weeks old.
- Weight at study initiation: less than 3.5 kg
- Housing: Individually housed in labelled cages with perforated floors (Scanbur, Denmark) and equipped with an automatic drinking system (ITL, Bergen, The Netherlands)
- Diet: Standard laboratory rabbit diet, ad libitum (Charles River Breeding and Maintenance Diet for Rabbits, Altromin, Germany)
- Water: Free access to tap-water
- Acclimation period: at least 5 days before start of treatment

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21
- Humidity (%): 50
- Air changes (per hr): 15
- Photoperiod (hrs dark / hrs light): 12

Test system

Type of coverage:

semiocclusive

Preparation of test site:

other: clipped

Vehicle:

water

Controls:

other: adjacent untreated areas served as control

Amount / concentration applied:

TEST MATERIAL
- Amount applied: 0.5 g

Duration of treatment / exposure:

4 hrs

Observation period:

3 days. skin reactions were assessed 1, 24, 48 and 72 hrs after the removal of the dressings

Number of animals:

3

Details on study design:

TEST SITE
- Approximately 24 hours before treatment, the dorsal fur was clipped with electric clippers, exposing an area of approximately 150 square centimeters (10x15 cm2).Each animal was treated by dermal application of 0.5 gram of the moistened test substance to the skin of one flank, using a Metalline patch of 2x3 cm. The patch was mounted on Micropore tape, which was wrapped around the abdomen and secured with Coban elastic bandage.

REMOVAL OF TEST SUBSTANCE
- Washing: The skin was cleaned of residual test substance using water
- Time after start of exposure: 4 hrs

SCORING SYSTEM:
The exposed skin areas were examined for signs of erythema and edema and the responses were scored (according to the grading system given in the OECD guideline 404) approximately 1 hr, and 24, 48 and 72 hours after removal of the patches.

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

mean

Time point:

other: mean (24+48+72h)

Score:

0

Max. score:

4

Results 2

Irritation parameter:

edema score

Basis:

mean

Time point:

other: mean (24+48+72h)

Score:

0

Max. score:

4

Irritant / corrosive response data:

No skin irritation and no corrosion was caused by 4 hours of exposure to the test article. All scores were zero at any time point.

Other effects:

No staining of the treated skin by the test substance was observed. No symptoms of systemic toxicity were observed in the animals during the test
period and no mortality occurred.

Applicant's summary and conclusion

Interpretation of results:

not irritating

Remarks:

Migrated information

Conclusions:

The test article did not cause any signs of irritation when applied semiocclusively for 4 hours to the rabbit skin.

Executive summary:

In a primary skin irritation/corrosion study following OECD guideline 404 and in compliance with GLP, three rabbits were exposed to 0.5 gram of the test substance for four hours. The test substance was moistened with water and then applied onto clipped skin using a semi-occlusive dressing. After 4 hours the dressing was removed and the skin was cleaned of residual test substance using water. Observations were made 1, 24, 48 and 72 hours after exposure. No skin irritation was caused by 4 hours of exposure to the test article. All scores for edema and erythema were zero at any time point. Based on the results and according to the EC criteria for classification and labeling requirements for dangerous substances and preparations (Guidelines in Commission Directive 93/21/EEC), the test article is regarded as non-irritating to the rabbit skin and does not have to be classified.