2-(4-methylphenoxy)-N-(1H-pyrazol-3-yl)-N-[(thiophen-2-yl)methyl]acetamide

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

27 November to 27 December 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

GLP study conducted according to OECD Guideline 420 without deviation.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Principles of method if other than guideline:

Not applicable

GLP compliance:

yes (incl. QA statement)

Remarks:

UK GLP Compliance Programme (inspected on July 18-20, 2017/ signed on November 28, 2017)

Test type:

fixed dose procedure

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

2-(4-methylphenoxy)-N-(1H-pyrazol-3-yl)-N-[(thiophen-2-yl)methyl]acetamide

EC Number:

815-961-9

Cas Number:

1374760-95-8

Molecular formula:

C17H17N3O2S

IUPAC Name:

2-(4-methylphenoxy)-N-(1H-pyrazol-3-yl)-N-[(thiophen-2-yl)methyl]acetamide

Test material form:

solid: particulate/powder

Details on test material:

Appearance: white to beige / white powder (solid)
Stability under test : Not specified, assumed to be stable
Storage conditions: Room temperature, protected from light, in the tightly closed original container.

Test animals

Species:

rat

Strain:

Wistar

Remarks:

RccHan™:WIST

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Envigo RMS (UK) Ltd.
- Females nulliparous and non-pregnant: Yes
- Age at study initiation: ca. 8-12 weeks
- Weight at study initiation: TBC
- Fasting period before study: overnight fast immediately before dosing and for approximately 3 to 4 hours after dosing.
- Housing: The animals were housed in groups of up to four in suspended solid-floor polypropylene cages furnished with woodflakes.
- Diet: 2014C Teklad Global Rodent diet supplied by Envigo RMS (UK) Limited, Oxon, UK, ad libitum
- Water: drinking water, ad libitum
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature: 19-25 °C
- Humidity: 30-70 %
- Animal room: The rate of air exchange was at least fifteen changes per hour. The animals were provided with environmental enrichment items which were considered not to contain any contaminant of a level that might have affected the purpose or integrity of the study.
- Photoperiod: 12 h dark / 12 h light

IN-LIFE DATES: From: 27 November 2017 To:27 December 2017

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

arachis oil

Details on oral exposure:

VEHICLE
- Concentration in vehicle: 30 and 200 mg/mL
- Amount of vehicle (if gavage): 10 mL/kg bw
- Justification for choice of vehicle: Arachis oil BP was used after a solubility trial (the test item did not dissolve/suspend in distilled water).

MAXIMUM DOSE VOLUME APPLIED: 10 mL/kg bw

DOSAGE PREPARATION: The test substance was formulated at concentrations of 30 and 200 mg/mL in the vehicle within 2 hours of being applied to the test system.

Doses:

300 and 2000 mg/kg bw

No. of animals per sex per dose:

1 female at 300 mg/kg bw
5 females at 2000 mg/kg bw

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations:
Mortality: Cages of rats were checked at least twice daily for any mortalities.
Clinical signs: Clinical observations were made 30 minutes, 1, 2, and 4 hours after dosing and then daily for 14 days.
- Frequency of weighing: Individual body weights were recorded on Day 0 (the day of dosing) and on Days 7 and 14.
- Necropsy of survivors performed: 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:

None

Results and discussion

Preliminary study:

Not applicable

Effect levels

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Remarks on result:

other: no mortality was observed

Mortality:

There were no deaths during the study.

Clinical signs:

No signs of systemic toxicity were noted during the observation period for any animals receiving 300 or 2000 mg/kg bw.

Body weight:

All animals receiving 300 or 2000 mg/kg bw showed expected gains in body weight over the observation period, except for one animal of the 2000 mg/kg bw group which showed expected gain during the first week but no gain in bodyweight during the second week.

Gross pathology:

All animals were killed at Day 14. No abnormalities were noted at necropsy.

Other findings:

None

Any other information on results incl. tables

None

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The oral LD50 of the test substance in female Wistar strain rat is estimated to be greater than 2000 mg/kg bw.
Under the test conditions, and according to the OECD TG 420 criteria, the LD50 cut-off value is considered to be greater than 5000 mg/kg bw, therefore it is not classified according to Regulation EC No. 1272/2008 (CLP) and to the GHS.

Executive summary:

In an acute oral toxicity study performed according to OECD Guideline 420 and in compliance with GLP, following a sighting test at dose levels of 300 mg/kg body weight and 2000 mg/kg body weight, a further group of four fasted females Wistar rats was given a single oral dose of test item, as a solution in DMSO, at a dose level of 2000 mg/kg body weight. Animals were then observed for mortality, clinical signs and body weights for 14 days and were all sacrificed for macroscopic examination.

 

There were no deaths and no clinical signs during the study. All animals receiving 300 or 2000 mg/kg bw showed expected gains in body weight over the observation period, except for one animal of the 2000 mg/kg bw group which showed expected gain during the first week but no gain in bodyweight during the second week. No abnormalities were noted in any animal at the macroscopic examination at study termination on Day 14.

Oral LD50 (female) > 2000 mg/kg bw

Under the test conditions, and according to the OECD TG 420 criteria, the LD50 cut-off value is considered to be greater than 5000 mg/kg bw, therefore it is not classified according to Regulation EC No. 1272/2008 (CLP) and to the GHS.

This study is considered as acceptable and satisfies the requirement for acute oral toxicity endpoint.