4-[[5-(anilino)carbonyl-2-methoxyphenyl]azo]-3-hydroxynaphthalene-2-carboxamide

Endpoint summary

Description of key information

Acute Oral Toxicity:

Introduction. The study was performed to assess the acute oral toxicity of the test material following a single oral administration in the Sprague-Dawley CD (Crl: CD^®(SD) IGSBR) strain rat.

Method. A group of three fasted females was treated with 2000 mg/kg bodyweight. This was followed by a group of three fasted animals of the other sex at the same dose level.

The test material was administered orally as a suspension in arachis oil BP. Clinical signs and bodyweight development were monitored during the study. All animals were subjected to gross necropsy examination.

Mortality. There were no deaths.

Clinical Observations. Pink staining of the fur was noted in all animals one to four days after dosing. There were no other signs of systemic toxicity.

Bodyweight. All animals showed expected gains in bodyweight over the study period.

Necropsy. No abnormalities were noted at necropsy.

Conclusion. The acute oral median lethal dose (LD₅₀) of the test material in the Sprague-Dawley CD (Crl: CD^®(SD) IGS BR) strain rat was estimated as being greater than 2500 mg/kg bodyweight. No mortalities were noted in animals treated with 2000 mg/kg bodyweight.

Acute Dermal Toxicity:

A study was performed to assess the acute dermal toxicity of the test item to the rat.

A group of 10 rats (5 males and 5 females) received a single topical application of the test substance, formulated at a maximum practical concentration in corn oil, at a dose level of 2000 mg/kg bodyweight, for a duration of 24 hours. All animals were killed and examined macroscopically on Day 15, the end of the observation period.

Clinical signs were confined to dark cerise coloured faeces seen in all animals on Days 3 through 5. No other clinical signs of reaction to treatment were observed during the study.

Very slight dermal irritation (Grade 1 oedema) was observed in 1 male following removal of the dressings, resolving completely by Day 3. A redisual cerise staining from the test material precluded assessment of the erythema in all animals up to Day 11 or 13. In addition localised spots and/or scabbing was noted in 1 female on Day 9 and 10. No dermal irritation was observed in the remaining animals during the study.

Low bodyweight gains were noted in 1 male and 4 females on Day 8 and for 3 females on Day 15. All other animals were considered to have achieved satisfactory bodyweight gains throughout the study.

Macroscopic examination revealed dark cerise staining at the dose site of 2 females. No other abnormalities were recorded at the macroscopic examination at study termination on Day 15.

The acute lethal dermal dose to rats of the test item was demonstrated to be greater than 2000 mg/kg bodyweight.

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

The study was conducted between 18 October 2000 and 08 November 2000.

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 423 (Acute Oral toxicity - Acute Toxic Class Method)

Qualifier:

according to guideline

Guideline:

EU Method B.1 tris (Acute Oral Toxicity - Acute Toxic Class Method)

GLP compliance:

yes (incl. QA statement)

Test type:

acute toxic class method

Specific details on test material used for the study:

Sponsors identification: ST383
Description: red powder
Batch number: S/No. 8793
Date received: 12 September 2000
Storage conditions: room temperature in the dark

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River (UK) Ltd., Margate, Kent, UK
- Females (if applicable) nulliparous and non-pregnant: yes
- Age at study initiation: ca. 8 weeks of age
- Weight at study initiation: Males = 225-246 g and Females = 204-216 g
- Fasting period before study: Overnight fast immediately before dosing
- Housing: housed in groups of 3 by sex in solid-floor polypropylene cages furnished with woodflakes.
- Diet (e.g. ad libitum): Rat and Mouse Expanded Diet No.1, Special Diets Services Ltd., Witham, Essex, UK (ad libitum)
- Water (e.g. ad libitum): drinking water (ad libitum)
- Acclimation period: >=5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19-25
- Humidity (%): 30-70
- Air changes (per hr): >=15
- Photoperiod (hrs dark / hrs light): 12 hrs light/12 hrs dark

Route of administration:

oral: gavage

Vehicle:

arachis oil

Details on oral exposure:

All animals were dose onced only by gavage, using a metal cannula attached to a graduated syringe. The volume administered to each animal was calculated according to the fasted bodyweight at the time of dosing. Treatment of animals was sequential. Sufficient time was allowed between each sex to confirm the survival of the previously dosed animals.

Doses:

2000 mg/kg

No. of animals per sex per dose:

3 animals per sex per dose (3 males at 2000 mg/kg and 3 females at 2000 mg/kg).

Control animals:

no

Details on study design:

The animals were observed for deaths or overt signs of toxicity 1/2, 1, 2 and 4 hours after dosing and subsquently once daily for fourteen days.

Individual bodyweights were recorded prior to dosing and 7 and 14 days after treatment.

At the end of the observation period the animals were killed cervical dislocation. All animals were subjected to gross pathological examination. This consisted of an external examinations and opening of the abdominal and thoracic cavities for examination of major organs. The appearance of any macroscopic abnormalties was recorded. No tissues were retained.

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 500 mg/kg bw

Based on:

test mat.

Mortality:

There were no deaths.

Clinical signs:

other: Pink staining of the fur was noted in all females one and two days dosing and in all males one to four days after dosing. No other signs of systemic toxicity were noted during the study.

Gross pathology:

No abnormalities were noted at necropsy.

Interpretation of results:

GHS criteria not met

Conclusions:

The acute oral median lethal dose (LD50) of the test material in the Sprague-Dawley CD (Crl: CD^(R) (SD) IGS BR) strain rat was estimated as being greater than 2500 mg/kg bodyweight.

No mortalies were noted in animals treated with 2000 mg/kg bodyweight.

Executive summary:

Introduction. The study was performed to assess the acute oral toxicity of the test material following a single oral administration in the Sprague-Dawley CD (Crl: CD^® (SD) IGSBR) strain rat. The method was designed to meet the requirements of the following:

• OECD Guidelines for the Testing of Chemicals No. 423 "Acute Oral Toxicity - Acute Toxic Class Method" (adopted 22 March 1996)
• Commision Directive 96/54/EC Method B1 tris Acute Toxicity (Oral) - Acute Toxic Class Method

Method. A group of three fasted females was treated with 2000 mg/kg bodyweight. This was followed by a group of three fasted animals of the other sex at the same dose level.

The test material was administered orally as a suspension in arachis oil BP. Clinical signs and bodyweight development were monitored during the study. All animals were subjected to gross necropsy examination.

Mortality. There were no deaths.

Clinical Observations. Pink staining of the fur was noted in all animals one to four days after dosing. There were no other signs of systemic toxicity.

Bodyweight. All animals showed expected gains in bodyweight over the study period.

Necropsy. No abnormalities were noted at necropsy.

Conclusion.The acute oral median lethal dose (LD₅₀) of the test material in the Sprague-Dawley CD (Crl: CD^®(SD) IGS BR) strain rat was estimated as being greater than 2500 mg/kg bodyweight. No mortalities were noted in animals treated with 2000 mg/kg bodyweight.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 500 mg/kg bw

Quality of whole database:

The available toxicity studies conducted on the substance are considered of high reliability and suitable for classification and labelleing, and risk characterisation.

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no study available

Acute toxicity: via dermal route

Link to relevant study records

Reference

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

The study was conducted between the 7 December 2001 and 21 December 2001.

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method B.3 (Acute Toxicity (Dermal))

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

GLP compliance:

yes (incl. QA statement)

Test type:

fixed dose procedure

Specific details on test material used for the study:

Identity:: ST463
Appearance: Magenta powder
Storage conditions: Room temperature
Lot number: 6558
Purity: 99.9%
Sample received: October 2002
Expiry: 15 0ctober 2001

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Harlan U.K.Ltd. Bicester,Oxon, Engiand
- Age at study initiation: 8-11 weeks old
- Weight at study initiation: 214-262 g
- Housing: The rats were allocated without concious bias to cages within the treatment group. They were housed individually in metal cages (RS Biotech Sub-Divisible Rodent Cages - polished stainless steel). The cages were fitted with grid floors to ensure rapid removal of waste material to undertrays. The cages were suspended in mobile stainless steel racks.
- Diet (e.g. ad libitum): Standard laboratory rodent diet (Special Diet Services RM1(E) SQC expanded pellet) (ad libitum)
- Water (e.g. ad libitum): drinking water (ad libitum)
- Acclimation period: 8 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 +/- 3
- Humidity (%): 40-70
- Photoperiod (hrs dark / hrs light): 12 hrs day/12 hrs night

Type of coverage:

semiocclusive

Vehicle:

corn oil

Details on dermal exposure:

Hair was removed from the dorso-lumbar region of each rat with electric clippers taking care to avoid damaging the skin,exposing an area equivalent to approxilnately 10% of the total body surface area.
The test substance was applied by spreading it evenly over the prepared skin. The treatnent area (approximately 50 mm x 50 mm) was covered with porous gauze held in place with a non-iritating dressing, and further covered by a waterproof dressing encircled firmly around the trunk of the animal. Treatment in this manner was performed on Day 1 (day of dosing) of the study only.

Duration of exposure:

24 hours - At the end of the 24 hours exposure period the dressing was carefully removed and the treated area of skin was washed mild detergent followed by warm water(30- 40°C) to remove any residual test substance. The treated area was blotted dry with absorbent paper.

Doses:

2000 mg/kg bodyweight

No. of animals per sex per dose:

5 animals per sex per dose (five males at 2000 mg/kg bodyweight and five females at 2000 mg/kg bodyweight)

Control animals:

no

Details on study design:

TEST SUBSTANCE PREPARATION:
The test item was formulated at a maximum practical concentration of 57% w/v in corn oil and administered at a dose volume of 3.51 ml/kg bodyweight.
The absorption of the test substance was not determined.
Characterisation of the homogeneity, stability and purity of the test substance was not undertaken in this studt and remained the responsibility of the Sponsor.

CONTROL ANIMALS:
No control animals were included in this study.

OBSERVATIONS:
Mortality:
Cages of rats were checked at least twice daily for mortalities.

Clinical signs:
Animals were observed soon after dosing and at frequent intervals for the remainder of Day 1. On subsequent days animals were observed once in the morning and again at the end of the experimental day (with the exception of Day 15 - morning only). The nature and severity of the clinical signs and time were recorded at each observations.
All animals were observed for 14 days after dosing.

Dermal responses:
Local dermal irritation at the treatment site was assessed daily using the following numerical scoring system:
Erythema and eschar formation:
No erythema = 0
Very slight erythema (barely perceptible) = 1
Well-defined erythema = 2
Moderate to severe erythema = 3
Severe erythema (beet redness) to eschar formation (injuries in depth) = 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 (raised approximately 1 mm) = 3
Severe oedema (raise more than 1 mm and extending beyond the area of exposure) = 4

Any lesion or reaction not covered by this scoring system was described.

Bodyweight:
The bodyweight of each rat was recorded on Days 1(prior to dosing), 8 and 15 bodyweight changes and group mean bodyweights were calculated.

TERMINAL STUDIES
Termination:
All animals were killed on Day 15 by carbon dioxide asphyxiation.

Macroscopic pathology:
All animals were subjected to a macroscoplc examination which consisted of opening the thoracic and abdominal cavities. The macroscopic appearance of all tissues was recorded.

Deviations from protocol:
There were no deviations from the protocol.

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

There were no deaths following a single dermal application of the test item to a group of 10 rats (5 males and 5 females) at a dose level of 2000 mg/kg bodyweight.

Clinical signs:

other: Clinical signs were confined to dark cerise coloured faeces seen in all animals on Days 3 through 5. No other clinical signs of reaction to treatment were observed during the study.

Gross pathology:

Macroscopic examination revealed dark cerise staining at the dose site of 2 females. No other abnormalities were recorded at the macroscopic examination at study termination on Day 15.

Other findings:

Very slight dermal irritation (Grade l oedema) was observed in 1 male following removal of the dressings, resolving completely by Day 3. A residual cerise staining from the test material precluded assessment of erythema in all animals up to Day 11 or 13. In addition localised spots and/or scabbing was noted in 1 fernale on Day 9 and 10. No dermal irritation was observed in the remaining animals during the study.

Interpretation of results:

GHS criteria not met

Conclusions:

The acute lethal dermal dose to rats of the test item was demonstrated to be greater than 2000 mg/kg bodyweight.

Executive summary:

A study was performed to assess the acute dermal toxicity of the test item to the rat. The method followed was that described in:

• EEC Methods for the determination of toxicity, Annex to Directive 92/69/EEC (Official Journal No. L383A, 29.12.92), Part B, Method B.3. Acute toxicity (dermal).
• OECD Guideline for Testing of Chemicals No. 402 "Acute Dermal Toxicity". Adopted: 24 February 1987.

A group of 10 rats (5 males and 5 females) received a single topical application of the test substance, formulated at a maximum practical concentration in corn oil, at a dose level of 2000 mg/kg bodyweight, for a duration of 24 hours. All animals were killed and examined macroscopically on Day 15, the end of the observation period.

Clinical signs were confined to dark cerise coloured faeces seen in all animals on Days 3 through 5. No other clinical signs of reaction to treatment were observed during the study.

Very slight dermal irritation (Grade 1 oedema) was observed in 1 male following removal of the dressings, resolving completely by Day 3. A redisual cerise staining from the test material precluded assessment of the erythema in all animals up to Day 11 or 13. In addition localised spots and/or scabbing was noted in 1 female on Day 9 and 10. No dermal irritation was observed in the remaining animals during the study.

Low bodyweight gains were noted in 1 male and 4 females on Day 8 (Nos. G2, G6, G7, G8 and G9) and for 3 females on Day 15 (Nos. G6, G7 and G9). All other animals were considered to have achieved satisfactory bodyweight gains throughout the study.

Macroscopic examination revealed dark cerise staining at the dose site of 2 females. No other abnormalities were recorded at the macroscopic examination at study termination on Day 15.

The acute lethal dermal dose to rats of the test item was demonstrated to be greater than 2000 mg/kg bodyweight.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Quality of whole database:

The available toxicity studies conducted on the substance are considered of high reliability and suitable for classification and labelleing, and risk characterisation.

Justification for classification or non-classification

In the CLP regulation acute toxicity means those adverse effects occurring following oral or dermal administration of a single dose of a substance or a mixture, or multiple doses given within 24 hours, or an inhalation exposure of 4 hours.

The substance does not meet the criteria for classification under the CLP regulations for acute toxicity via the oral route based on the result of an acute oral toxicity study, which gave a LD₅₀of > 2500 mg/kg bodyweight, which is above the classification cut-off value ( ≤2000 mg/kg bodyweight) for acute oral toxicity.

The substance does not meet the criteria for classification under the CLP regulations for acute toxicity via the dermal route based on the result of an acute dermal toxicity study, which gave a LD₅₀of > 2000 mg/kg bodyweight, which is above the classification cut-off value ( ≤2000 mg/kg bodyweight) for acute dermal toxicity.