2-[(4-chloro-2-nitrophenyl)azo]-N-(2,3-dihydro-2-oxo-1H-benzimidazol-5-yl)-3-oxobutyramide

Endpoint summary

Description of key information

The test material is not irritating to skin under test conditions. Since the test conditions were more stringent than required by OECD TG 404 (i.e. 24 h treatment, occlusive coverage, and scarified skin instead of 4 h treatment, semi-occlusive coverage, and intact skin) the test results are considered adequate to fulfill the endpoint requirements.

The test material is very slightly irritating to the eyes under the test conditions, which are basically in accordance with todays standard methods regarding dosing, exposure duration, scoring system and reading time points. 4/6 animals showed a conjunctiva redness score of  one 24 h after removal of the test item, the effect being fully reversible within 72 h for all animals except one. No other effects were observed.

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records

Reference

Reference 1

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 14 MAR 1977 to 17 MAR 1977

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: FDA guideline (minor deviations from OECD guideline)

Reason / purpose for cross-reference:

reference to same study

Qualifier:

according to guideline

Guideline:

other: FDA guideline (Federal register 38, No. 187, 27.9.1973, p.27019)

Deviations:

no

GLP compliance:

no

Remarks:

study was performed previous to GLP implementation

Species:

rabbit

Strain:

other: New Zealand

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Weight at study initiation: 1.5 - 2.0 kg
- Housing: single
- Diet: ERKA 8300 (Futtermittelwerke Robert Koch oHG, Hamm, Germany), ad libitum
- Water: ad libitum

Type of coverage:

occlusive

Preparation of test site:

other: clipped/intact or clipped/scarified

Vehicle:

unchanged (no vehicle)

Controls:

not required

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 500 mg

Duration of treatment / exposure:

24 h (i.e. removal of the patch 24 h after start of treatment)

Observation period:

start of treatment: 0 h (zero hour)
end of treatment: removal of the patch 24 h after start of treatment
first reading: 24 h after start of treatment (= 0 h after end of treatment)
second reading: 48 h after start of treatment (= 24 after end of treatment)
third reading: 72 h after start of treament (= 48 h after end of treatment)

Number of animals:

6

Details on study design:

TEST SITE
- Area of exposure: 2.5 x 2.5 cm
- Type of wrap if used: gauze patch

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

SCORING SYSTEM: erythema and edema scores (0-4)

Skin was evaluated immediately, 24 h and 48 h after removal of the patch. Mean values for readings were calculated for each animal.

Irritation parameter:

erythema score

Basis:

mean

Time point:

other: 24 and 48 h after end of treatment

Score:

0

Max. score:

4

Reversibility:

other: not relevant since no effect

Irritation parameter:

edema score

Basis:

mean

Time point:

other: 24 and 48 h after end of treatment

Score:

0

Max. score:

4

Reversibility:

other: not relevant since no effect

Irritant / corrosive response data:

Immediately after removal of patch no erythema score could be determined due to pigment overlay. Edema score at this time point was 0 for all animals. No edema or eryhthema were seen 24 and 48 h after removal of the patch (score 0).
Results on scarified skin showed identical results.

Interpretation of results:

GHS criteria not met

Remarks:

Regulation (EC) no 1272/2008

Conclusions:

The test material is not irritating to skin under these test conditions.
This conclusion is legitimate even though the applied testing regime differs from today's standard methods. Since the test conditions were more stringent than required by OECD TG 404 (i.e. 24 h treatment, occlusive coverage, and scarified skin instead of 4 h treatment, semi-occlusive coverage, and intact skin) the test results are considered adequate to fulfill the endpoint requirements.

Executive summary:

The test material was tested for skin irritancy according to FDA guidelines. Both intact and scarified skin sites of six rabbits were exposed to 0.5 g test substance for 24 h under occlusive conditions and the skin responses were observed for 48 hours after end of exposure. Immediately after removal of patch no erythema score could be determined due to pigment overlay. No erythema were seen at the later observation time points. No edema were seen at any time point (score 0). The test item is not irritating under these test conditions.

Reference 2

Endpoint:

skin corrosion: in vitro / ex vivo

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

an in vitro skin irritation study does not need to be conducted because adequate data from an in vivo skin irritation study are available

other:

Reference 3

Endpoint:

skin irritation: in vivo

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Justification for type of information:

see Rationale and Justification for the Analogue Read-Across Approach – Nanoforms and Bulk Forms (Chapter 13)

Reason / purpose for cross-reference:

read-across source

Irritation parameter:

erythema score

Basis:

mean

Time point:

24/48 h

Score:

0

Max. score:

4

Reversibility:

other: not relevant since no effect

Irritation parameter:

edema score

Basis:

mean

Time point:

24/48 h

Score:

0

Max. score:

4

Reversibility:

other: not relevant since no effect

Interpretation of results:

GHS criteria not met

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Eye irritation

Link to relevant study records

Reference

Reference 1

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 14 MAR 1977 to 17 MAR 1977

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Meets important criteria of today standard methods even though not examined until full reversibility of effects seen.

Reason / purpose for cross-reference:

reference to same study

Qualifier:

according to guideline

Guideline:

other: FDA guideline (Federal Register Vol. 38, nr. 187, p. 27019, 1973)

Deviations:

no

Principles of method if other than guideline:

Pigment Orange 36

GLP compliance:

no

Remarks:

study was performed previous to GLP implementation

Species:

rabbit

Strain:

other: New Zealand

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Housing: single
- Diet: ERKA 8300 (Futtermittelwerke Robert Koch oHG, Hamm, Germany), ad libitum
- Water: ad libitum

Vehicle:

unchanged (no vehicle)

Controls:

not required

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 100 mg

Duration of treatment / exposure:

24 h after exposure eyes were washed with physiological saline.

Observation period (in vivo):

72 h with observation time points at 1, 7, 24, 48 and 72 h after application.

Number of animals or in vitro replicates:

6

Details on study design:

REMOVAL OF TEST SUBSTANCE
- Washing (if done): yes
- Time after start of exposure: 24 h

SCORING SYSTEM: according to Draize Scale.

TOOL USED TO ASSESS SCORE: loupe / fluorescein (at 48 and 72 h reading)

Irritation parameter:

cornea opacity score

Basis:

mean

Time point:

24/48/72 h

Score:

0

Max. score:

4

Reversibility:

other: not relevant since no effect

Irritation parameter:

iris score

Basis:

mean

Time point:

24/48/72 h

Score:

0

Max. score:

2

Reversibility:

other: not relevant since no effect

Irritation parameter:

conjunctivae score

Remarks:

redness

Basis:

animal: #1 and #5 each

Time point:

24/48/72 h

Score:

0

Max. score:

3

Reversibility:

other: not relevant since no effect

Irritation parameter:

conjunctivae score

Remarks:

redness

Basis:

animal: #2 and #3 each

Time point:

other: mean of 24, 48 and 72 h

Score:

0.67

Max. score:

3

Reversibility:

fully reversible within: 72 h

Irritation parameter:

conjunctivae score

Remarks:

redness

Basis:

animal #4

Time point:

other: mean of 24, 48 and 72 h

Score:

1

Max. score:

3

Reversibility:

not fully reversible within: 72 h

Remarks on result:

other: The effect was slight and fully reversible in the remaining animals within the observation period of 72 h. Therefore full reversibility was expected in animal #4 within 7 days

Irritation parameter:

conjunctivae score

Remarks:

redness

Basis:

animal #6

Time point:

24/48/72 h

Score:

0.33

Max. score:

3

Reversibility:

fully reversible within: 48 h

Irritation parameter:

chemosis score

Basis:

mean

Time point:

24/48/72 h

Score:

0

Max. score:

4

Reversibility:

other: not relevant since no effect

Irritant / corrosive response data:

Individual animal data for animal #1/#2/#3/#4/#5/#6 at time point 1, 7, 24, 48 and 72 h.
cornea score: all scores 0
iris score: all scores 0
conjunctivae redness: 1/1/1/1/1/1, 1/1/1/1/1/1, 0/1/1/1/0/1, 0/1/1/1/0/0, 0/0/0/1/0/0
chemosis: 1/1/1/1/1/0, 2/1/1/1/2/2, 0/0/0/0/0/0, 0/0/0/0/0/0, 0/0/0/0/0/0

Other effects:

No other effects reported

Interpretation of results:

GHS criteria not met

Remarks:

Regulation (EC) no 1272/2008

Conclusions:

The test material is very slightly irritating to the eyes under the test conditions which are basically in accordance with todays standard methods regarding dosing, exposure duration, scoring system and reading time points. 4/6 animals showed a conjunctiva redness score of one 24 h after removal of the test item, the effect being fully reversible within 72 h for all animals except one. No other effects were observed.
The slight effect does not result in a classification of the test item according to the classification criteria of Regulation (EC) No 1272/2008.

Executive summary:

Test material was subject to a test of eye irritancy according to FDA guidelines (Fed. Reg. Vol. 38, No. 187, p. 27019, 1973). 100 mg of substance were applied to one eye of six animals. The eyes were washed 24 h after application and eye responses were noted for 72 h after start of the exposure. Only slight effects could be observed (conjunctiva redness score of 1 in 4/6 animals after 24 h, which was fully reversible within 72 h at all animals except one). No other effects could be observed in any animal. Overall effects observed are minimal and it is anticipated that this slight conjunctival effect which remained until 72 hours in one animal might be reversible within a prolonged observation period.  

Reference 2

Endpoint:

eye irritation: in vitro / ex vivo

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

an in vitro eye irritation study does not need to be conducted because adequate data from an in vivo eye irritation study are available

other:

Reference 3

Endpoint:

eye irritation: in vivo

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Justification for type of information:

see Rationale and Justification for the Analogue Read-Across Approach – Nanoforms and Bulk Forms (Chapter 13)

Reason / purpose for cross-reference:

read-across source

Irritation parameter:

cornea opacity score

Basis:

mean

Time point:

24/48/72 h

Score:

0

Max. score:

4

Reversibility:

other: no effect

Irritation parameter:

iris score

Basis:

mean

Time point:

24/48/72 h

Score:

0

Max. score:

4

Reversibility:

other: no effect

Irritation parameter:

chemosis score

Basis:

mean

Time point:

24/48/72 h

Score:

0

Max. score:

4

Reversibility:

other: no effect

Irritation parameter:

conjunctivae score

Basis:

animal: #1 & #5

Time point:

24/48/72 h

Score:

0

Max. score:

3

Reversibility:

other: no effect

Irritation parameter:

conjunctivae score

Basis:

animal: #2 & #3

Time point:

24/48/72 h

Score:

0.67

Max. score:

3

Reversibility:

fully reversible within: 72 h

Irritation parameter:

conjunctivae score

Basis:

animal #4

Time point:

24/48/72 h

Score:

1

Max. score:

3

Reversibility:

not fully reversible within: 72 h

Irritation parameter:

conjunctivae score

Basis:

animal #6

Time point:

24/48/72 h

Score:

0.33

Max. score:

3

Reversibility:

fully reversible within: 48 h

Interpretation of results:

GHS criteria not met

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

No classification for skin irritation. No adverse effects observed.

The slight effect on conjunctivae does not result in a classification of the test item for eye irritation according to the classification criteria of Regulation (EC) No 1272/2008.