Isopentyl p-methoxycinnamate

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

12 December 1994 to 15 December 1994

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Cross-reference

Cross-reference 1

Reason / purpose for cross-reference:

reference to same study

Cross-reference 2

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1995

Report date:

1995

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Principles of method if other than guideline:

not applicable

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Isopentyl p-methoxycinnamate

EC Number:

275-702-5

EC Name:

Isopentyl p-methoxycinnamate

Cas Number:

71617-10-2

Molecular formula:

C15H20O3

IUPAC Name:

isopentyl p-methoxycinnamate

Test animals

Species:

rabbit

Strain:

other: SPF albino

Details on test animals or test system and environmental conditions:

Animals = Four female SPF albino rabbits weighting 2.1-2.4 kg of the stock Mol:Russian from Mollegaard Breeding and Research Centre A/S, Ejby, DK-4623 Lille Skensved were used.
Housing = The study took place in animal room No. 1 provided with filtered air with a temperature of 21±3°C, relative humidity of 55±15% and air changes 10 times/h. The room was illuminated to give a 24 h cycle of 12 h light and 12 h darkness. Ligh was on from 6 a.m. to 6 p.m. During a pre-period of at least 1 week and throughout the experiment, the rabbits were caged in single 62 x 52 cm PPO cages with perforated floor.
Diet = A pelleted complete rabbit diet "Altromin 2123" from Chr. Petersen, DK-4100 Ringsted, Denmark was available ad libitum. Analyses for major nutritive components and significant contaminants are performed regularly on the diet.
Drinking water = The animals had free access to bottles with domestic quality drinking water acidified with hydrochloric acid to pH 2.5 in order to prevent microbial growth. Analyses for possible contaminants are performed regularly.

Test system

Type of coverage:

semiocclusive

Preparation of test site:

other: clipped

Vehicle:

other: Ethanol 96 % and diethyl phtalate (DEP) in a ration 1 : 1 (w/w)

Controls:

yes, concurrent vehicle

Amount / concentration applied:

Test concentrations (w/w): 100, 20, 10, 5, and %

Duration of treatment / exposure:

After an exposure of 4 h, the tape and patches were removed and the treated skin was cleaned with soap and luke warm water. The skin reactions were read 1 hour later.

Observation period:

After an exposure of 4 hours the tape and patches were removed and the treated skin was cleaned with soap and luke warm water. The skin reactions were read 1 h later.
Reading was also performed at 24, 48, and 72 h after termination of exposure.

Number of animals:

Four female SPF albino rabbits were used.

Details on study design:

The day before the experiment was started, the rabbits were weighted and an area of 10 x 10 cm on the back was clipped as closely as possible with an electric clipper.
On the experimental day, the rabbits were physically restrained on a test table, and the clipped area was divided into 6 test sites: 2 anterior located test sites, 2 centrally located test sites and 2 posterior located test sites. To each of 6 gauze patches (2.5 x 2.5 cm), 0.5 mL of 1 of the test concentrations or the vehicle was applied and the patches were placed on the appropriate test site at the back of each rabbit. The gauze patches were secured with a semi-occlusive dressing by means of a 1-cm wide adhesive tape and fixed with Scanpor tape, 4.5 cm width, loosely wound round the trunk. The application schedule was made by a computerized randomization programme.
After an exposure of 4 h, the tape and patches were removed and the treated skin was cleaned with soap and luke warm water. The skin reactions were read 1 h later. Reading was also performed at 24, 48, and 72 h after termination of exposure.

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0.33

Max. score:

1

Reversibility:

not specified

Remarks on result:

no indication of irritation

Results 2

Irritation parameter:

erythema score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Max. score:

0

Reversibility:

not specified

Results 3

Irritation parameter:

erythema score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Max. score:

0

Reversibility:

not specified

Results 4

Irritation parameter:

erythema score

Basis:

animal #4

Time point:

24/48/72 h

Score:

0

Max. score:

0

Reversibility:

not specified

Results 5

Irritation parameter:

edema score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Max. score:

0

Reversibility:

not specified

Results 6

Irritation parameter:

edema score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Max. score:

0

Results 7

Irritation parameter:

edema score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Max. score:

0

Results 8

Irritation parameter:

edema score

Basis:

animal #4

Time point:

24/48/72 h

Score:

0

Max. score:

0

Irritant / corrosive response data:

see section "Any other information on results incl. tables" below

Other effects:

no other effects were observed

Any other information on results incl. tables

Under the experimental conditions described in the report, the mean score for erythema and oedema in the 4 rabbits used were as follow:

Test concentration	100 %	20 %	10 %	5 %	1 %	Vehicle
Erythema	0.3	0.0	0.0	0.0	0.0	0.0
Oedema	0.0	0.0	0.0	0.0	0.0	0.0

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Isopentyl p-methoxycinnamate was found to be not irritating to the skin of rabbits.

Executive summary:

The primary skin irritant effect of Neo Heliopan E1000 was investigated according to the method recommended in the current OECD guideline no. 404, "Acute Dermal Irritation/ Corrosion", 1992, and in the current EC guideline B.4 "Acute toxicity (skin irritation)", dated 29.12.1992. The study was extended to investigate 5 different concentrations of the test article and a vehicle control on each animal.

Four albinos rabbits were exposed to different concentrations of the test article at 6 skin sites on the back. After 4 h of exposure, the test article was removed and the skin was examined 1, 24, 48, and 72 h after termination of exposure.

Slight skin erythma was observed at 1 to 48 h after termination of exposure of the neat test article. Apart from that, no abnormalities were observed.

Accordingly, isopentyl p-methoxycinnamate was rated as being not irritating to the skin of rabbits.