N-(2-ethylhexyl)-1-[[2-methyl-4-[(2-methylphenyl)azo]phenyl]azo]naphthalen-2-amine

Endpoint summary

Description of key information

Acute oral toxicity: LD50 > 2000 mg/kg bw, EU Method B.1 tris, GLP compliant
Acute dermal toxicity: LD50 > 2000 mg/kg bw, EU Method B.3, GLP compliant

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:

17.9.2012 -2.10.2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

yes

Test type:

acute toxic class method

Limit test:

yes

Species:

rat

Strain:

Wistar

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Age at study initiation: 8-10 weeks
- Weight at study initiation: 147-163 g
- Fasting period before study: 20 h. Feed was given to the animals 3 hours after application of the test substance.
- Housing: Animal room with monitoring conditions – 3 animals of one sex in one plastic breeding cage Velaz T4
- Diet (e.g. ad libitum): standard pelleted diet ad libitum
- Water (e.g. ad libitum): Drinking tap water ad libitum
- Acclimation period: Min. 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 3°C
- Relative 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: 12.09.2012
Experimental part of study: 17.09.2012 - 02.10.2012

Route of administration:

oral: gavage

Vehicle:

olive oil

Details on oral exposure:

VEHICLE
- Lot/batch no. (if required): 5211201
- Purity: Pharmaceutical quality

MAXIMUM DOSE VOLUME APPLIED: The single volume of administered suspension was 1mL/100 g of animal body weight.

CLASS METHOD (if applicable)
- Rationale for the selection of the starting dose: The test procedure starting dose of 2000 mg/kg was selected. The test substance at this dose level was administered sequentially to two groups of three females (application with time distance 24 hours). No death of animals was observed and therefore the testing was finished.

Doses:

2000 mg/kg b.w.

No. of animals per sex per dose:

3 females (step 1), 3 females (step 2)

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing:
- Body weight: Before application, 8th day and 15th day before euthanasia of animals. Average body weight in a group was calculated from individual body weights. Body weight increments were calculated from body weight at the start of the study, the first week and at the end of the study.
- Mortality: Daily
- Clinical examination: After application, the animals were observed individually. The first day observations were made twice, 30 minutes and three hours after application. The second day, observations were made twice, in the morning and the afternoon, and daily thereafter for 14 days. Observations included changes in the skin and fur, eyes, visible mucous membranes, behaviour of animals, somatomotor activity, reactions to stimuli, and presence of lacrimation, salivation and discharge from nostrils, function of respiratory, digestive and urogenital system. The results of observations were recorded.
- Pathological examination: All test animals survived to the end of the study were sacrificed on the 15th day by injection of veterinary preparation T61 (1 mL i.v.) and gross necropsy was carried out. Nutritious status, body surface, body foramina, thoracic, abdominal and cranial cavity were evaluated. Al gross macroscopic changes of organs were recorded.
- Necropsy of survivors performed: Yes

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

No deaths

Clinical signs:

other: The clinical signs of intoxication (piloerection and gibbous posture) were detected 30 minutes after the 1st day of application in all six animals. Detected clinical changes did not influence the classification of the test substance.

Gross pathology:

No pathologic macroscopic changes were diagnosed during pathological examination.

Interpretation of results:

other: Not classified (EU criteria)

Conclusions:

The LD50 of the test material is > 2000 mg/kg of body weight.

Executive summary:

The acute toxic effects of the test substance were assessed according to the Method B.1 tris: Acute Oral Toxicity - Acute Toxic Class Method, Council Regulation (EC) No.440/2008, and OECD Test Guideline 423.

The test substance was administered in a single dose as solution in vehicle (olive oil), given orally via gavage to two groups of three female Wistar rats.

The dosing was performed sequentially in two groups of three females: group No. 1 - first step using the starting dose of 2000 mg/kg of body weight and group No. 2 - second step using the same dose.

The test substance administered at the dose of 2000 mg/kg caused no deaths. The clinical signs of intoxication (piloerection and gibbous posture) were detected 30 minutes after the first day of application in all six animals. No pathologic macroscopic changes were diagnosed during pathological examination.

The LD50 of the test material is > 2000 mg/kg of body weight.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Quality of whole database:

The study is GLP compliant and has Klimisch score 1. The quality of the database is therefore considered to be good.

Acute toxicity: via inhalation route

Link to relevant study records

Reference

Endpoint:

acute toxicity: inhalation

Data waiving:

other justification

Justification for data waiving:

other:

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:

22.8.2012 - 8.9.2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Deviations:

no

GLP compliance:

yes

Test type:

standard acute method

Limit test:

yes

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Weight at study initiation: 195-237 g (males), 157-162 g (females)
- Housing: Animal room with monitored conditions – one animal in one plastic cage with sterilised soft wood shavings.
- Diet (e.g. ad libitum): standard pelleted diet ad libitum
- Water (e.g. ad libitum): Drinking tap water ad libitum
- Acclimation period: At least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 3 °C
- Relative humidity (%): 30-70 %
- Air changes (per hr): Approximately 15 air changes per hour
- Photoperiod (hrs dark / hrs light): Light: 12 hour light/12 hour dark

STUDY TIME SCHEDULE
Experimental starting date: 22.8.2012
Experimental completion date: 8.9.2012

Type of coverage:

semiocclusive

Vehicle:

unchanged (no vehicle)

Details on dermal exposure:

TEST SITE
- Area of exposure: Approximately 24 hours before application, a skin area of approximately 6 x 6 cm on the back of the animals was shaved.
- % coverage: aprox. 10 % of the body surface
- Type of wrap if used: The application site was covered by mull and held in contact by plaster (strapping).

REMOVAL OF TEST SUBSTANCE
- Washing (if done): The remains of the test material was wiped off with water.
- Time after start of exposure: 24 hrs

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): According to its body weight and the dose.

Duration of exposure:

24 hrs

Doses:

2000 mg/kg b.w.

No. of animals per sex per dose:

5 males and 5 females.
A pre-test was performed with 1 male and 1 females of those groups of 5 animals.

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing:
- Body weight: Before application, 8th and 15th day of study. body weight increments were calculated from the body weight at the start of the study, during the first week and at the end of the study.
- Mortality: daily
- Clinical signs: After application, the animals were observed individually. On the first day observations were made twice, 30 minute and three hours after application. On the second day observations were made twice, in the morning and afternoon, and daily thereafter for 14 days. Observations included changes in skin and fur, eyes, visible mucous membranes, nutritive condition, autonomic and central nervous systems, psychic activity, somatomotor activity, reactions to stimuli, function of respiratory, circulatory, digestive and urogenital system. Also, presence of tremors, convulsions, salivation, diarrhoea, lethargy, sleep and coma were carefully observed.

- Necropsy of survivors performed: All test animals surviving to the end of study were sacrificed on the 15th day by injection of veterinary preparation T61 (1 mL i.v.) and gross necropsy was carried out. Nutritional state, body surface, body foramina, thoracic, abdominal and cranial activity were evaluated. All gross macroscopic changes of organs and tissues were recorded.

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

There were no deaths.

Clinical signs:

other: Clinical signs of toxicity - diarrhoea were observed to the 3rd day of the study, gibbous posture were observed to the 4th day of the study and skin around anus coloured by excrements persisted to the 5th day of the study.

Gross pathology:

No macroscopic changes were diagnosed during pathological examination of all animals.

Interpretation of results:

other: Not classified (EU criteria)

Conclusions:

The LD50 (dermal) of the test substance for rats of both sexes is higher than 2000 mg/kg of body weight.

Executive summary:

The test material was assessed for acute dermal toxicity according to Method B.3 - Acute toxicity (Dermal), Council Regulation (EC) No.440/2008, and according to OECD Test Guideline No.402 - Acute Dermal Toxicity, Adopted 24th February 1987. 

The study was performed as limit test: Two groups of animals – 5 males and 5 females at the dose of 2000 mg/kg of body weight. The test substance was applied on the shaved skin of the test animals in delivered form for 24 hours.

The test animals were observed for 14 days after exposure test substance, afterwards they were sacrificed, and the necropsy for macroscopic examination of the organs was performed.

The test substance applied at the dose of 2000 mg/kg of body weight did not cause death of animals. Clinical signs of toxicity were observed, notably diarrhoea was observed to the 3rd day of the study, gibbous posture were observed to the 4th day of the study and skin around anus coloured by excrements persisted to the 5th day of the study.

No macroscopic changes were diagnosed during pathological examination.

According to the results of study, the value of LD50 (dermal) of the test material, for rats of both sexes > 2000 mg/kg of body weight. 

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Quality of whole database:

The study is GLP compliant and has Klimisch score 1. The quality of the database is therefore considered to be good.

Additional information

ORAL

The acute toxic effects of the test substance were assessed according to the Method B.1 tris: Acute Oral Toxicity - Acute Toxic Class Method, Council Regulation (EC) No.440/2008, and OECD Test Guideline 423.

The test substance was administered in a single dose as solution in vehicle (olive oil), given orally via gavage to two groups of three female Wistar rats.

The dosing was performed sequentially in two groups of three females: group No. 1 - first step using the starting dose of 2000 mg/kg of body weight and group No. 2 - second step using the same dose.

The test substance administered at the dose of 2000 mg/kg caused no deaths. The clinical signs of intoxication (piloerection and gibbous posture) were detected 30 minutes after the first day of application in all six animals. No pathologic macroscopic changes were diagnosed during pathological examination.

The LD50 of the test material is > 2000 mg/kg of body weight.

INHALATION

In accordance with column 2 of REACH Annex VIII, the Acute toxicity inhalation study (required in section 8.5.2) does not need to be conducted. The dermal route is provided to the oral route as more appropriate than inhalation route (with respect to the low vapour pressure and the use of the substance).

DERMAL

The test material was assessed for acute dermal toxicity according to Method B.3 - Acute toxicity (Dermal), Council Regulation (EC) No.440/2008, and according to OECD Test Guideline No.402 - Acute Dermal Toxicity, Adopted 24th February 1987. 

The study was performed as limit test: Two groups of animals – 5 males and 5 females at the dose of 2000 mg/kg of body weight. The test substance was applied on the shaved skin of the test animals in delivered form for 24 hours.

The test animals were observed for 14 days after exposure test substance, afterwards they were sacrificed, and the necropsy for macroscopic examination of the organs was performed.

The test substance applied at the dose of 2000 mg/kg of body weight did not cause death of animals. Clinical signs of toxicity were observed, notably diarrhoea was observed to the 3rd day of the study, gibbous posture were observed to the 4th day of the study and skin around anus coloured by excrements persisted to the 5th day of the study.

No macroscopic changes were diagnosed during pathological examination.

According to the results of study, the value of LD50 (dermal) of the test material, for rats of both sexes > 2000 mg/kg of body weight. 

Justification for classification or non-classification

In accordance with the criteria for classification as defined in Annex I, Regulation (EC) No 1272/2008, the substance does not require classification with respect to acute toxicity.