1,3-diethyldiphenylurea

Endpoint summary

Description of key information

The testing strategy for skin  irritation was followed:
no literature data and studies
assessment of physicochemical properties and pH measurement - approx. 7 (by contact with universal indicator pH strip moistened with water)
In vitro skin corrosion test - negative result
In vitro skin irritation test - negative result
In vivo skin irritation/corrosion test - negative result
The testing strategy for eye irritation/corrosion was followed:
no literature data and studies
assessment of results of skin irritation/corrosion tests
assessment of physicochemical properties
In vitro BCOP test - negative result
In vivo eye irritation/corrosion test - negative result

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records

Reference

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

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

yes

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

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

Irritation parameter:

erythema score

Basis:

mean

Time point:

24/48/72 h

Score:

0

Max. score:

4

Irritation parameter:

edema score

Basis:

mean

Time point:

24/48/72 h

Score:

0

Max. score:

4

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.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Eye irritation

Link to relevant study records

Reference

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

28.11.-5.12.2011

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method B.5 (Acute Toxicity: Eye Irritation / Corrosion)

Deviations:

no

GLP compliance:

yes

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Source: breeding farm VELAZ s.r.o., Koleč u Kladna, Czech Republic
- Age at study initiation: 2 – 5 months
- Weight at study initiation: 3.1 – 3.6 kg
- Housing: individually in metallic cages
- Diet (e.g. ad libitum): standard pelleted diet TM-MAK 1 for rabbits and guinea pigs
- Water (e.g. ad libitum): drinking tap water

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 +/- 3°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: 28. 11. – 05. 12. 2011

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.1 g

Duration of treatment / exposure:

72 h

Observation period (in vivo):

1, 24, 48, 72 hours

Number of animals or in vitro replicates:

1 male - initial test
2 males - confirmatory test

Details on study design:

REMOVAL OF TEST SUBSTANCE
- Washing (if done): noSCORING SYSTEM: according to the grading system given in Method B.5 Acute Toxicity: Eye Irritation/Corrosion. Council Regulation (EC) No.440/2008.

TOOL USED TO ASSESS SCORE: After recording the observations at 24 hours, the eyes of rabbit were examined with the aid of fluorescein and the ophthalmoscopy.

Irritation parameter:

cornea opacity score

Basis:

mean

Time point:

24/48/72 h

Score:

0

Max. score:

4

Irritation parameter:

iris score

Basis:

mean

Time point:

24/48/72 h

Score:

0

Max. score:

2

Irritation parameter:

conjunctivae score

Basis:

mean

Time point:

24/48/72 h

Score:

0

Max. score:

3

Irritation parameter:

chemosis score

Basis:

mean

Time point:

24/48/72 h

Score:

0

Max. score:

4

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

The following changes were observed on eye at 1 hour after application: conjunctivae – diffuse, crimson colour, individual vessels not easily discernible in all rabbits and some swelling above normal in one rabbit. At 24, 48 and 72 hours after application no irritating effects of eye was observed in all animals.
No clinical signs of systemic intoxication were detected.

Evaluation of results after single application demonstrated that the test substance, Centralit, is not irritating for eye of rabbit.

Executive summary:

The test substance, Centralit, was tested for the assessment of eye irritation/corrosion effects using albino rabbit (New Zealand Albino breed).

The test was performed according to the Method B.5 Acute Toxicity: Eye Irritation/Corrosion. Council Regulation (EC) No.440/2008, published in O.J. L 142, 2008.

The test was performed initially using one animal. Because a corrosive or severe irritating effects were not observed in initial test, the response was confirmed using two additional animals.

The following changes were observed on eye at 1 hour after application: conjunctivae – diffuse, crimson colour, individual vessels not easily discernible in all rabbits and some swelling above normal in one rabbit (No. 16). At 24, 48 and 72 hours after application no irritating effects of eye was observed in all animals.

No clinical signs of systemic intoxication were detected.

Evaluation of results after single application demonstrated that the test substance, Centralit, is not irritating for eye of rabbit.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Justification for selection of skin irritation / corrosion endpoint:
In vivo study

Justification for selection of eye irritation endpoint:
In vivo study

Justification for classification or non-classification

Based on the available data, the substance is not classified.