2-hydroxy-N-1H-1,2,4-triazol-3-ylbenzamide

Endpoint summary

Description of key information

The Acute Oral Toxicity in the Rat – Fixed Dose Procedure (WK90WT, Envigo Research Limited) study was performed to assess the acute oral toxicity of the test item in the Wistar strain rat.

The acute oral median lethal dose (LD50) of the test item in the female Wistar strain rat was estimated to be greater than 2000 mg/kg body weight (Globally Harmonized Classification System − Unclassified).

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:

29 August 2017 - 25 September 2017

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)

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes (incl. QA statement)

Test type:

fixed dose procedure

Limit test:

no

Species:

rat

Strain:

Wistar

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
Female Wistar (RccHan™:WIST) strain rats were supplied by Envigo RMS (UK) Limited, Oxon, UK. On receipt the animals were randomly allocated to cages. The females were nulliparous and non-pregnant. After an acclimatization period of at least 5 days the animals were selected at random and given a number unique within the study by indelible ink-marking on the tail and a number written on a cage card. At the start of the study the animals were 8 to 12 weeks of age. The body weight variation did not exceed ±20% of the mean body weight at the start of treatment.

ENVIRONMENTAL CONDITIONS
The temperature and relative humidity were set to achieve limits of 19 to 25 °C and 30 to 70% respectively. The rate of air exchange was at least fifteen changes per hour and the lighting was controlled by a time switch to give 12 hours continuous light and 12 hours darkness.

IN-LIFE DATES:
From: 29 August 2017
To: 25 September 2017

Route of administration:

oral: gavage

Vehicle:

arachis oil

Details on oral exposure:

VEHICLE
For the purpose of the study the test item was freshly prepared, as required, as a suspension in arachis oil BP. Arachis oil BP was used because the test item did not dissolve/suspend in distilled water.

MAXIMUM DOSE VOLUME APPLIED: 10 mL/kg
Using available information on the toxicity of the test item, 2000 mg/kg was chosen as the starting dose.

Doses:

2000 mg/kg

No. of animals per sex per dose:

4

Control animals:

no

Details on study design:

- Duration of observation period following administration: 30 minutes, 1, 2, and 4 hours after dosing and then daily for 14 days.
- Frequency of observations and weighing: Morbidity and mortality checks were made twice daily, early and late during normal working days, and once daily at weekends and public holidays. Individual body weights were recorded on Day 0 (the day of dosing) and on Days 7 and 14.
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight,organ weights, histopathology, other: At the end of the observation period the animals were killed by cervical dislocation. All animals were subjected to gross necropsy. This consisted of an external examination and opening of the abdominal and thoracic cavities. The appearance of any macroscopic abnormalities was recorded. No tissues were retained.

Statistics:

not specified

Preliminary study:

not specified

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

There were no deaths.

Clinical signs:

No signs of systemic toxicity were noted during the observation period.

Body weight:

All animals showed expected gains in body weight over the observation period.

Gross pathology:

No abnormalities were noted at necropsy.

Other findings:

not specified

Interpretation of results:

GHS criteria not met

Conclusions:

The acute oral median lethal dose (LD50) of the test item in the female Wistar strain rat was estimated to be greater than 2000 mg/kg body weight (Globally Harmonized Classification System − Unclassified).