Butanoic acid, 4-[[4-[7-chloro-6-(1,1-dimethylethyl)-3H-pyrazolo[1,5-b][1,2,4]triazol-2-yl]phenyl]amino]-4-oxo-, tetradecyl ester

Endpoint summary

Description of key information

Oral

Key study:- Jessup (2004a) 'Acute oral toxicity study (fixed dose) in the rat' conducted in line with OECD Guideline 420 and EU Method B.1. The LD50 of the test substance in the rat was determined to be >2000 mg/kg bw.

Dermal

Key study:- Jessup (2004b) 'Acute dermal toxicity study in the rat' conducted in line with OECD Guideline 402 and EU Method B.3.

The LD50 of the test substance in the rat was determined to be >2000 mg/kg bw.

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:

28 August 2003 to 16 September 2003

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 420 (Acute Oral Toxicity - Fixed Dose Method)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.1 bis (Acute Oral Toxicity - Fixed Dose Procedure)

Deviations:

no

GLP compliance:

yes

Test type:

fixed dose procedure

Limit test:

yes

Species:

rat

Strain:

Sprague-Dawley

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Age at study initiation: 9 to 10 weeks of age
- Weight at study initiation: 194.43 to 225.30 grams
- Fasting period before study: Fasted overnight
- Housing: Animals were housed in an Association for Assessment and Accreditation of Laboratory Animal Care International-accredited vivarium in accordance with the Guide for the Care and Use of Laboratory Animals (National Research Council, 1996). The rats were singly housed in suspended, stainless-steel, wire mesh cages. Cages and racks were washed once a week. Absorbent paper, used to collect excreta, was changed at least three times a week.
- Diet: Certified Rodent Diet (pelleted) was available ad libitum.
- Water: Water was available ad libitum through an automatic watering system. The source of the water was the local public water system.
- Acclimation period: The animals were isolated upon arrival and allowed to acclimate for a period of 5 days. Animals were judged to be healthy prior to testing.

ENVIRONMENTAL CONDITIONS
- Temperature: 20.8 - 24.6 °C
- Humidity: 43.4 - 71.0 %
- Photoperiod: A photoperiod of 12 hours of light was maintained.

Route of administration:

oral: gavage

Vehicle:

CMC (carboxymethyl cellulose)

Remarks:

0.5 % aqueous suspension

Details on oral exposure:

VEHICLE
- Concentration in vehicle: For the 300 and 2000 mg/kg dose levels, the test substance was administered as a 3 or 20 % suspension in the vehicle, respectively.
- Amount of vehicle (if gavage): The vehicle was a 0.5 % aqueous suspension of carboxymethylcellulose.

TEST SUBSTANCE EXPOSURE
- A single dose of the test substance was administered by gavage to animals that had been fasted overnight.

Doses:

300 and 2000 mg/kg dose levels

No. of animals per sex per dose:

In a preliminary sighting study, an initial dose of 300 mg/kg of the test substance was administered to a single female rat. Since no signs of toxicity were noted for this rat, a higher dose of 2000 mg/kg was administered to a second female rat. Based on the results of the sighting study, 2000 mg/kg was administered to an additional four female rats.

Control animals:

not specified

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Body weights were collected on Days 0 (prior to treatment), 7, and 14. Animals were observed three times on the day of dosing (Day 0), and once each day thereafter for the duration of the experiment. Observations included, but were not limited to, examination of the hair, skin, eyes, mucous membranes, motor activity, feces, urine, respiratory system, circulatory system, autonomic nervous system, central nervous system, and behavior patterns.
- Necropsy of survivors performed: yes

Statistics:

No statistical procedures were required during the study. No dose/mortality curve was constructed since graphs become statistically useful only with the use of large numbers of animals and dose groups.

Preliminary study:

An initial dose of 300 mg/kg of the test substance was administered to a single female rat. Since no signs of toxicity were noted for this female, a higher dose of 2000 mg/kg was administered to a second female rat. No mortality or abnormal clinical signs were noted during the sighting study. Therefore, 2000 mg of the test substance/kg body weight was administered to an additional four female rats.

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

No mortality was observed during the 14-day observation period for rats administered a dose of 2000 mg/kg of the test substance.

Clinical signs:

other: No clinical abnormalities were observed at anytime during the observation period.

Gross pathology:

No test substance-related changes were observed at necropsy and no tissue was collected for microscopic examination.

Interpretation of results:

other: Not classified in accordance with EU criteria

Conclusions:

Under the conditions of the test, the acute oral LD50 of the test substance was determined to be greater than 2000 mg/kg for female rats.

Executive summary:

In a GLP compliant study conducted in line with OECD Guideline 420 and EU Method B.1 bis, the acute toxicity of butanoic acid, 4-[[4-[7-chloro-6-(1,1-dimethylethyl)-3H-pyrazolo[1,5-b][1,2,4]triazol-2-yl]phenyl]amino]-4-oxo, tetradecyl ester to female rats was investigated.

An initial dose of 300 mg/kg of the test substance was administered to a single female rat. Since no signs of toxicity were noted for this female, a limit dose of 2000 mg/kg was administered to a second female rat. Since no signs of toxicity were noted for the 2000 mg/kg female, an additional four female rats were administered the limit dose.

For the five female rats that were administered the limit dose, the test substance was administered as a 20 % suspension in an aqueous carboxymethylcellulose vehicle solution. No mortality or abnormal clinical signs were observed for the 300 or 2000 mg/kg dose groups at any time during the 14-day observation period. One 2000 mg/kg female rat lost a small amount of weight (6.46 grams) during the second week of the study. However, this female rat gained weight over the 14-day observation period. All other rats gained weight during both weeks of the study. No test substance-related changes were observed at necropsy and no tissues

were collected for histological examination.

The acute oral LD50 for this test substance was greater than 2000 mg/kg for female rats and requires no toxicity classification under current EU requirements.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Quality of whole database:

The available study was conducted in accordance with standardised guidelines and under GLP conditions. The quality of the database is therefore considered to be high.

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:

18 September 2003 to 2 October 2003

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Deviations:

no

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

yes

Test type:

standard acute method

Limit test:

yes

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Age at study initiation: The male rats were 8 to 9 weeks of age and the female rats were 10 to 11 weeks of age.
- Weight at study initiation: The male rats weighed 250.90 to 278.64 grams and the female rats weighed 215.20 to 252.91 grams.
- Fasting period before study: Not reported
- Housing: Animals were housed in an Association for Assessment and Accreditation of Laboratory Animal Care International-accredited vivarium in accordance with the Guide for the Care and Use of Laboratory Animals (National Research Council, 1996). The rats were singly housed in suspended, stainless-steel, wire mesh cages. Cages and racks were washed once a week. Absorbent paper, used to collect excreta, was changed at least three times a week.
- Diet: Certified Rodent Diet (pelleted) was available ad libitum.
- Water: Water was available ad libitum through an automatic watering system. The source of the water was the local public water system.
- Acclimation period: The animals were isolated upon arrival and allowed to acclimate for a period of 5 days. Animals were judged to be healthy prior to testing.

ENVIRONMENTAL CONDITIONS
- Temperature: 21.4 - 23.8 °C
- Humidity: 41.3 - 60.7 %
- Photoperiod: A photoperiod of 12 hours of light was maintained.

Type of coverage:

occlusive

Vehicle:

water

Details on dermal exposure:

TEST SITE
- Area of exposure: Not reported
- % coverage: Not reported
- Type of wrap if used: A fiber pad and an occlusive wrap to hold the test substance in place

REMOVAL OF TEST SUBSTANCE
- Washing (if done): At the end of the exposure period, any residual test substance was removed with running water.
- Time after start of exposure: 24 hours

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): The test substance, a solid, was administered at 2000 mg/kg moistened with water.

Duration of exposure:

24 hours

Doses:

2000 mg/kg

No. of animals per sex per dose:

Five male and five female

Control animals:

not specified

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Body weights were measured on Days 0 (prior to treatment), 7, and 14. Animals were observed at least once during the exposure period, and once each day thereafter for the duration of the experiment. Observations included, but were not limited to, examination of the hair, skin, eyes, mucous membranes, motor activity, feces, urine, respiratory system, circulatory system, autonomic nervous system, central nervous system, and behavior patterns.
- Necropsy of survivors performed: yes

Statistics:

No statistical procedures were required during the study. No dose/mortality curve was constructed since graphs become statistically useful only with the use of large numbers of animals and dose groups.

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

No mortality was observed during the 14-day observation period for rats administered a dose of 2000 mg/kg of the test substance.

Clinical signs:

other: No abnormal clinical signs were observed.

Gross pathology:

No treatment-related changes were observed at necropsy, and no tissue was collected for microscopic examination.

Interpretation of results:

other: Not classified in accordance with EU criteria

Conclusions:

Under the conditions of the test, the acute dermal LD50 for the test substance was determined to be greater than 2000 mg/kg for male and female rats.

Executive summary:

In a GLP compliant study conducted in line with OECD Guideline 402 and EU Method B.3, the acute toxicity of butanoic acid, 4-[[4-[7-chloro-6-(1,1-dimethylethyl)-3H-pyrazolo[1,5-b][1,2,4]triazol-2-yl]phenyl]amino]-4-oxo, tetradecyl ester to rats was investigated.

Male and female rats were administered a single limit dose of 2000 mg/kg of the test substance topically. The test substance was administered moistened with water. No abnormal clinical signs were noted at any time during the 14-day observation period. No mortality was observed, and all animals gained weight. No treatment-related changes were observed at necropsy, and no tissues were collected for histological examination.

The acute dermal LD50 for this test substance was greater than 2000 mg/kg for male and female rats and requires no toxicity classification in line with current EU requirements.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Quality of whole database:

The available study was conducted in accordance with standardised guidelines and under GLP conditions. The quality of the database is therefore considered to be high.

Additional information

Oral

The key study (Jessup, 2004a) was performed in compliance with GLP and to OECD Guideline 420 and EU Method B.1 with a sufficient level of detail to assess the quality of the presented data. The study was performed to a good standard in line with accepted, standardised guidelines and was assigned a reliability score of 1 using the principles for assessing data quality as set out in Klimisch et al. (1997). The LD50 of the test substance in the rat was determined to be >2000 mg/kg bw.

Dermal

The key study (Jessup, 2004b) was performed in compliance with GLP and to OECD Guideline 402 and EU Method B.3 with a sufficient level of detail to assess the quality of the presented data. The study was performed to a good standard in line with accepted, standardised guidelines and was assigned a reliability score of 1 using the principles for assessing data quality as set out in Klimisch et al. (1997). The LD50 of the test substance in the rat was determined to be >2000 mg/kg bw/day.

Inhalation

No study required on the basis of lack of exposure.

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 via the oral and dermal routes.