Ethanone, 1-(3-methyl-2-benzofuranyl)-

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1997-02-24 to 1997-02-28

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

Test guideline 1

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

1992-12-29

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Version / remarks:

1992

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

-

EC Number:

429-100-6

EC Name:

-

Cas Number:

23911-56-0

Molecular formula:

C11H10O2

IUPAC Name:

1-(3-methyl-1-benzofuran-2-yl)ethan-1-one

Test animals

Species:

rabbit

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Weight at study initiation: 2.0-2.3 kg
- Housing: The rabbits were caged individually in PPO/HIPS Noryl®) cages (floor area: 2576 cm^2) with perforated floor. The trays under the cages were cleaned 2-3 times a week.
- Diet: Ad libitum
- Water: Ad libitum
- Acclimation period: At least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 ± 3
- Humidity (%): 55 ± 15
- Air changes (per hr): 10
- Photoperiod (hrs dark / hrs light): 12/12

Test system

Type of coverage:

not specified

Preparation of test site:

clipped

Vehicle:

other: Ethanol 96% and diethylphthalate (DEP) in ratio 1 : 1 (w/w)

Controls:

yes, concurrent vehicle

Amount / concentration applied:

TEST MATERIAL
- Amount applied: 0.5 mL
- Concentration: 100%, 25%, 10%, 5% and 1%

VEHICLE
- Amount applied: 0.5 mL
- Concentration: Ethanol 96% and diethylphthalate (DEP) in ratio 1 : 1 (w/w)

Duration of treatment / exposure:

4 hours

Observation period:

From the beginning of treatment until 72 hours after treatment

Number of animals:

4 rabbits, each was treated with 6 different concentrations of the test item

Details on study design:

TEST SITE
- Area of exposure: An area of 10 x 10 cm was clipped and divided into 6 test sites. Each test site was covered with a 2.5 x 2.5 cm gauze patch.
- % coverage: Not specified
- Type of wrap: The gauze patches were secured with 2.5 cm wide adhesive tape and fixed with Scanpor tape (5 cm width). Thereafter Nobifix (6 cm width) was loosely wound round the trunk.

REMOVAL OF TEST SUBSTANCE
- Washing: Yes, the treated skin was cleaned with lukewarm water
- Time after start of exposure: 4 hours

OBSERVATION TIME POINTS
The skin reactions were read 1 hour after the end of treatment. Reading was also made 24, 48 and 72 hours after termination of exposure.

SCORING SYSTEM
- Method of calculation: The scores for erythema and oedema formation for the last 3 readings at 24, 48 and 72 hours for each rabbit were obtained separately and divided by 3. The results are the mean scores for erythema and oedema formation for the individual rabbits for each test concentration. The scoring system is described under "Any other information on materials and methods, incl. tables", table 1.

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

edema score

Basis:

animal #4

Time point:

24/48/72 h

Score:

0

Max. score:

4

Reversibility:

other: no effects observed

Remarks on result:

no indication of irritation

Remarks:

The results are given for a 100 % test concentration. Also a 25%, 10%, 5% and 1% test concentration showed a score of 0.

Results 2

Irritation parameter:

edema score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Max. score:

4

Reversibility:

other: no effects observed

Remarks on result:

no indication of irritation

Remarks:

The results are given for a 100 % test concentration. Also a 25%, 10%, 5% and 1% test concentration showed a score of 0.

Results 3

Irritation parameter:

edema score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Max. score:

4

Reversibility:

other: no effects observed

Remarks on result:

no indication of irritation

Remarks:

The results are given for a 100 % test concentration. Also a 25%, 10%, 5% and 1% test concentration showed a score of 0.

Results 4

Irritation parameter:

edema score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Max. score:

4

Reversibility:

other: no effects observed

Remarks on result:

no indication of irritation

Remarks:

The results are given for a 100 % test concentration. Also a 25%, 10%, 5% and 1% test concentration showed a score of 0.

Results 5

Irritation parameter:

erythema score

Basis:

animal #4

Time point:

24/48/72 h

Score:

0

Max. score:

4

Reversibility:

other: no effects observed

Remarks on result:

no indication of irritation

Remarks:

The results are given for a 100 % test concentration. Also a 25%, 10%, 5% and 1% test concentration showed a score of 0.

Results 6

Irritation parameter:

erythema score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Max. score:

4

Reversibility:

other: no effects observed

Remarks on result:

no indication of irritation

Remarks:

The results are given for a 100 % test concentration. Also a 25%, 10%, 5% and 1% test concentration showed a score of 0.

Results 7

Irritation parameter:

erythema score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Max. score:

4

Reversibility:

other: no effects observed

Remarks on result:

no indication of irritation

Remarks:

The results are given for a 100 % test concentration. Also a 25%, 10%, 5% and 1% test concentration showed a score of 0.

Results 8

Irritation parameter:

erythema score

Basis:

animal #1

Time point:

24/48/72 h

Score:

1

Max. score:

4

Reversibility:

not specified

Remarks on result:

probability of weak irritation

Remarks:

The results are given for a 100 % test concentration. A test concentration of 25% showed an erythema score of 0.33 and 10%, 5% and 1% test concentrations showed a score of 0.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The test item was found to be not irritating to the skin.

Executive summary:

The primary skin irritant effect of the test item was investigated in a GLP-compliant study according to the method recommended in OECD Guideline 404. The study was extended to investigate five different concentrations of the test article and a vehicle control on each animal. Four rabbits were exposed to different concentrations of the test article at six skin sites on the back. After 4 hours of exposure the test article was removed and the skin was examined 1, 24, 48 and 72 hours after termination of exposure. Under the experimental conditions described in this report, the mean score for erythema and oedema in the four rabbits used was as follows:

 

Test concentration	100%	25%	10%	5%	1%	Vehicle
Erythema	0.3	0	0	0	0	0
Oedema	0	0	0	0	0	0

 

The test item should thus not be classified as a skin irritant.