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

Endpoint summary

Description of key information

Female rats were subjected to test acute oral toxicity according to the acute class method (OECD TG 423, Limit test). The test substance was administered by gavage at the limit dose of 2000 mg/kg bw to two groups of 3 animals. All treated animals expressed mild clinical signs of toxicity following the treatment. A slightly ruffled fur was observed in some animals which lasted until day 3, at the most. Moreover all animals showed a hunched posture for a few hours after the treatment.

No animal died within the observation period, resulting in a LD50 > 2000mg/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:

From 31 MAY 2006 to 23 Jun 2006

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study (EU method B.1 tris; OECD TG 423)

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:

other: HanRCC: WIST (SPF)

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: RCC Ltd, Laboratory Animal Services, Füllinsdorf, Switzerland
- Age at study initiation: 12 weeks
- Fasting period before study: 18 to 19 h
- Housing: Macrolon cages (type 4) in groups of three
- Diet: peletted standard Provimi Kliba 3433 rat/mouse maintenance diet (batch no. 001/06, Provimi Kliba AG, Kaiseraugst, Switzerland); ad libitum
- Water: community tap water; ad libitum
- Acclimation period: 7 days


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22+-3
- Humidity (%): between 30 to 70
- Photoperiod (hrs dark / hrs light): 12/12

Route of administration:

oral: gavage

Vehicle:

water

Details on oral exposure:

VEHICLE
- Concentration in vehicle: 0.2 g/mL
MAXIMUM DOSE VOLUME APPLIED: 10 mL/kg

Doses:

2000 mg/kg bw

No. of animals per sex per dose:

2 groups of 3 animals

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations: at least daily
- Frequency of weighing: weekly
- Necropsy of survivors performed: yes

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Remarks on result:

other: no animals died within the 14 day observation period

Mortality:

- no deaths occurred

Clinical signs:

other: - all animals expressed mild clinical signs of toxicity following the treatment - slight ruffeled fur was noted in 3 animals from 30 minutes reading until day 2 and in 1 animal from the 1hour reading until day 3 - hunched posture was seen, respectively, i

Gross pathology:

- animals killed at the end of the observation period showed no macroscopically visible changes

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Single application of the limit dose of 2000 mg test substance per kg bw did not cause lethality in female HanRCC: Wist rats during the 14 day observation period, resulting in a LD50 > 2000 mg/kg bw.

Executive summary:

Female rats were subjected to test acute oral toxicity according to the acute class method (OECD TG 423, Limit test). The test substance was administered by gavage at the limit dose of 2000 mg/kg bw to two groups of 3 animals. All treated animals expressed mild clinical signs of toxicity following the treatment. A slightly ruffled fur was observed in some animals which lasted until day 3, at the most. Moreover all animals showed a hunched posture for a few hours after the treatment.

No animal died within the observation period, resulting in a LD50 > 2000mg/kg bw.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

LD0

Value:

> 2 000 mg/kg bw

Quality of whole database:

reliable

Acute toxicity: via inhalation route

Link to relevant study records

Reference

Endpoint:

acute toxicity: inhalation

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

the study does not need to be conducted because exposure of humans via inhalation is not likely taking into account the vapour pressure of the substance and/or the possibility of exposure to aerosols, particles or droplets of an inhalable size

Endpoint conclusion

Endpoint conclusion:

no study available

Acute toxicity: via dermal route

Link to relevant study records

Reference

Endpoint:

acute toxicity: dermal

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

the study does not need to be conducted because the substance does not meet the criteria for classification as acute toxicity or STOT SE by the oral route and no systemic effects have been observed in in vivo studies with dermal exposure (e.g. skin irritation, skin sensitisation)

Endpoint conclusion

Endpoint conclusion:

no study available

Quality of whole database:

reliable

Justification for classification or non-classification

No classification.

The test material did not cause mortality after oral gavage of 2000 mg/kg bw to rats.