Reaction mass of 2-ethylhexyl (3-isocyanato-4-methylphenyl)carbamate and 2-ethylhexyl (5-isocyanato-2-methylphenyl)carbamate and 2-ethylhexyl (3-isocyanato-2-methylphenyl)carbamate

Skin irritation / corrosion

Administrative data

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: The study was performed to a recognised guideline in accordance with generally accepted scientific principles.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1981

Report date:

1981

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: FHSA Procedure - Draize Scoring method (Federal Register, Vol. 38, No. 187, Sept. 27, 1973, §1500.41)

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

Reaction mass of 2-Ethylhexyl N-(5-isocyanato-2-methylphenyl)carbamate and 2-Ethylhexyl N-(3-isocyanato-4-methylphenyl)carbamate and N,N'-(4-Methyl-1,3-phenylene)bis(carbamic acid) C,C'-bis(2-ethylhexyl) ester

EC Number:

937-955-6

Molecular formula:

components with the molecular formulae C25H42N2O4 and C17H24N2O3

IUPAC Name:

Reaction mass of 2-Ethylhexyl N-(5-isocyanato-2-methylphenyl)carbamate and 2-Ethylhexyl N-(3-isocyanato-4-methylphenyl)carbamate and N,N'-(4-Methyl-1,3-phenylene)bis(carbamic acid) C,C'-bis(2-ethylhexyl) ester

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Diet (e.g. ad libitum): Appropriate Wayne diet ad libitum.
- Water (e.g. ad libitum): ad libitum.

Test system

Type of coverage:

occlusive

Preparation of test site:

other: both intact and abraded sited clipped free of hair.

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

0.5 mL

Duration of treatment / exposure:

24 hours

Observation period:

72 hours

Number of animals:

6

Details on study design:

No further detail on the study design is given, but the guideline is quoted: Federal Register, Vol. 38, No. 187, Sept. 27, 1973, §1500.41: Method of testing primary irritant substances

Primary irritation to the skin is measured by a patch-test technique on the abraded and intact skin of the albino rabbit, clipped free of hair. A minimum of six subjects are used in abraded and intact skin tests. Introduce under a square patch, such as surgical gauze measuring 1 inch by 1 inch and two single layers thick, 0.5 millilitre (in the case the of liquids) or 0.5 gram (in the case of solids and semisolids) of the test substance. Dissolve solids in a appropriate solvent and apply the solution as for liquids.
The animals are immobilised with patches secured in place by adhesive tape. The entire trunk of the animal is then wrapped with an impervious material such as rubberised cloth for the 24 hour period of exposure. This material aids in maintaining the test patches in position and retards the evaporation of volatile substances.
After 24 hours of exposure, the patches are removed and the resulting reactions evaluated on the basis of the designated values in the following table.

Erythema and eschar formation:
No erythema 0
Very slight erythema (barely perceptable) 1
Well-defined erythema 2
Moderate to severe erythema 3
Severe erythema (beet redness) or eschar formation (injuries in depth) preventing erythema reading 4

Oedema formation:
No oedema 0
Very slight oedema (barely perceptible) 1
Slight oedema (edges of area well-defined by definite raising) 2
Moderate oedema (edges raised approximately 1 millimetre) 3
Severe oedema (raised more than 1 millimetre and extending beyond the area of exposure) 4

Readings are again made at the end of a total of 72 hours (48 hours after the first reading). An equal number of exposures are made on areas of skin that have been previously abraded. The abrasions are minor incisions through the stratum corneum, but not sufficiently deep to disturb the derma or to produce bleeding. Evaluate the reactions of the abraded skin at 24 hours and 72 hours. Add values for erythema and eschar formation at 24 and 72 hours for intact skin to the value son abraded skin at 24 and 72 hours.
Similarly, add the values for oedema formation at 24 and 72 hours for intact and abraded skin (four values). The total of the eight values is divided by four to give the primary irritation score.

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

primary dermal irritation index (PDII)

Basis:

other: Overall score

Time point:

24/48/72 h

Score:

1.2

Results 2

Irritation parameter:

erythema score

Basis:

animal: mean

Time point:

24/48/72 h

Max. score:

4

Reversibility:

not specified

Remarks on result:

other: Not specified

Results 3

Irritation parameter:

edema score

Basis:

animal: mean

Time point:

24/48/72 h

Max. score:

4

Reversibility:

not fully reversible within:

Remarks on result:

other: Not specified

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Primary Irritation Score equal to 1.2.

Executive summary:

The skin irritation potential of the test material was assessed in New Zealand White rabbits according to the FHSA Procedure - Draize Scoring method (Federal Register, Vol. 38, No. 187, Sept. 27, 1973, §1500.41)

The material was applied to the clipped intact and abraded skin of 6 animals and occluded for 24 hours. Skin reactions were observed and evaluated after 24 and 72 hours, resulting in a primary irritation score equal to 1.2.