1,3-diethyldiphenylurea

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

21.11.-28.11.2011

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2011

Report date:

2011

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

1,3-diethyldiphenylurea

EC Number:

201-645-2

EC Name:

1,3-diethyldiphenylurea

Cas Number:

85-98-3

Molecular formula:

C17H20N2O

IUPAC Name:

1,3-diethyl-1,3-diphenylurea

Test material form:

solid: crystalline

Details on test material:

- Name of test material (as cited in study report): Centralit
- Physical state: white solid crystalline
- Analytical purity: 99.9 % (w/w)
- Lot/batch No.: 0500906
- Expiration date of the lot/batch: 16.9.2016
- Stability under test conditions: stable
- Storage condition of test material: in dry room at the temperature < 40°C

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: breeding farm VELAZ s.r.o., Koleč u Kladna, Czech Republic
- Weight at study initiation: 3.0 – 3.1 kg
- Housing: individually in cages without bedding
- Diet (e.g. ad libitum): pelleted standard diet TM-MAK 1 for rabbits and guinea-pigs
- Water (e.g. ad libitum): drinking tap water
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 17-23°C
- Humidity (%): 30-70%
- Air changes (per hr): approximately 15 air changes per hour
- Photoperiod (hrs dark / hrs light): 12 hour light/12 hour dark

STUDY TIME SCHEDULE
Animal supply: 16. 11. 2011
Experimental part of study: 21.11. – 28. 11. 2011

Test system

Type of coverage:

semiocclusive

Preparation of test site:

shaved

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.5 g

Duration of treatment / exposure:

4 h

Observation period:

1, 24, 48, 72 h

Number of animals:

2 males (confirmatory test)

Details on study design:

TEST SITE
- Area of exposure: 6x6 cm
- Type of wrap if used: gauze patch, foil and cellulose cotton and held in place with non-irritating tape - Spofaplast

REMOVAL OF TEST SUBSTANCE
- Washing (if done): no

SCORING SYSTEM: according to the grading system given in Method B.4 Acute toxicity: Dermal Irritation/Corrosion, Council Regulation (EC) No.440/2008

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

mean

Time point:

24/48/72 h

Score:

0

Max. score:

4

Results 2

Irritation parameter:

edema score

Basis:

mean

Time point:

24/48/72 h

Score:

0

Max. score:

4

Applicant's summary and conclusion

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

The test substance, Centralit, was tested for acute dermal irritation/corrosion.
Three rabbits were exposed to 0.5 g of test substance, applied onto clipped skin for 4 hours using a semi-occlusive dressing. Skin reactions were evaluated after patch removal and observations were made at the 1, 24, 48 and 72 hours after exposure.
No symptoms of irritation were observed on the skin.
No symptoms of systemic toxicity were observed in the animals during the test period.
No skin irritation was caused by 4-hour exposure to Centralit.

Executive summary:

The test substance, Centralit, was tested in the study for acute dermal irritation/corrosion. Rabbits (New Zealand Albino breed) were used for the test.

Test was performed according to Method B.4 - Acute Toxicity: Dermal Irritation/Corrosion, Council Regulation (EC) No.440/2008, published in O.J. L 142, 2008.

Three rabbits were exposed to 0.5 g of test substance, applied onto clipped skin for 4 hours using a semi-occlusive dressing. Skin reactions were evaluated after patch removal and observations were made at 1, 24, 48 and 72 hours after exposure.

At first the test substance was applied on the skin of one rabbit (test animal No. 13). Rabbit No. 13 was investigated 3 minutes, 1 hour and 4 hours after application of the test substance.

No evidence of a corrosive effect or symptoms of irritation were observed on the skin after application.

In confirmatory test, two others rabbits (rabbit No. 14 and No. 15) were used with 4-hour exposition period.

No symptoms of irritation on the skin were observed. No other signs of intoxication were observed.

No skin irritation was caused by 4-hour exposure to Centralit.