4,5-bis(hydroxymethyl)-2-phenyl-1H-imidazole

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 06 October 2021 to April 2022

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

GLP study conducted according to the OECD TG 423 without any deviation.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2022

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

17 December 2001

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

Inspection date (French COFRAC): January 5-7, 2021 / Opinion (GIPC): 26 July 2021

Test type:

acute toxic class method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

4,5-bis(hydroxymethyl)-2-phenyl-1H-imidazole

EC Number:

262-911-1

EC Name:

4,5-bis(hydroxymethyl)-2-phenyl-1H-imidazole

Cas Number:

61698-32-6

Molecular formula:

C11H12N2O2

IUPAC Name:

[4-(hydroxymethyl)-2-phenyl-1H-imidazol-5-yl]methanol

Test material form:

solid: particulate/powder

Details on test material:

- Appearance: white to light-pink powder
- Storage: Keep away from heat and sources of ignition. Store in tightly closed container. Store in a well-ventilated place. Store in a cool, dark place.

Specific details on test material used for the study:

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: room temperature, in a dry place
- Stability and homogeneity of the test material in the vehicle/solvent under test conditions (e.g. in the exposure medium) and during storage: stable under storage conditions. No analytical monitoring during the study.
- Stability in the medium, i.e. sensitivity of the test material to hydrolysis and/or photolysis: No analytical monitoring during the study.
- Solubility and stability of the test material in the solvent/vehicle and the exposure medium: Olive oil was chosen as it produced the most suitable formulation at the requested concentration for the preparations.
- Reactivity of the test material with the incubation material used (e.g. plastic ware): none reported.

TREATMENT OF TEST MATERIAL PRIOR TO TESTING
- Treatment of test material prior to testing (e.g. warming, grinding): The preparations were stirred using a vortex to obtain thick yellow solutions just before the administration
- Preliminary purification step (if any): none
- Final concentration of a dissolved solid, stock liquid or gel: 0.3 or 2 g in q.s. 10 mL.

Test animals

Species:

rat

Strain:

Sprague-Dawley

Remarks:

SPF Caw

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River (F-69210 Saint-Germain-Nuelles)
- Females (if applicable) nulliparous and non-pregnant: yes
- Age at study initiation: 8 weeks old
- Weight at study initiation: 179-216 g on Day 0
- Fasting period before study: Food was removed on day 1 and then redistributed 4 hours after the test item administration.
- Housing: by group of three in solid-bottomed clear polycarbonate cages with a stainless-steel mesh lid. Each cage contains sawdust bedding which was changed at least 2 times a week.
- Historical data: available
- Diet (e.g. ad libitum): ad libitum (ENVIGO – 2014 & 2016)
- Water (e.g. ad libitum): ad libitum (tap-water from public distribution system)
- Acclimation period: at least 5 days
- Microbiological status when known: no contamination. Analysis carried out once every six months by Bureau veritas - Eurofins (FRANCE).

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19 to 25
- Humidity (%): 30 to 70
- Air changes (per hr): at least 10
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: From: 12 October 2021 To: 24 November 2021

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

olive oil

Details on oral exposure:

VEHICLE
- Concentration in vehicle: 0.3 or 2 g in vehicle
- Amount of vehicle (if gavage): q.s. 10 mL
- Justification for choice of vehicle: Olive oil was chosen as it produced the most suitable formulation at the requested concentration for the preparations. Distilled water was tested first as vehicle but the test item was immiscible in distilled water.

MAXIMUM DOSE VOLUME APPLIED: 10 mL/kg bw

CLASS METHOD
- Rationale for the selection of the starting dose: as per OECD TG 423 recommendation, when there is no information on the substance to be tested, for animal welfare reasons, it is recommended to use the starting dose of 300 mg/kg bw.

Doses:

300 (females) and 2000 mg/kg bw (females)

No. of animals per sex per dose:

3

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Systematic examinations were carried out to identify any behavioural or toxic effects on the major physiological functions 30 minutes, 1 hour ± 6 minutes, 3 hours ± 30 minutes, 4 hours ± 30 minutes, 24 and 48 hours ± 2 hours after administration of the test item and continued daily for 14 days.
The animals were weighed on day D0 (just before administering the test item) then on day 2, day 7, and day 14.
- Necropsy of survivors performed: yes (gross necropsy)
- Clinical signs including body weight: yes
- Other examinations performed: not required

Statistics:

None

Results and discussion

Effect levels

Key result

Sex:

female

Dose descriptor:

LD50 cut-off

Effect level:

5 000 mg/kg bw

Based on:

test mat.

Mortality:

One mortality was noted in an animal treated at the dose of 2000 mg/kg body weight 6 days after the treatment (1/6). In the absence of clinical signs and the presence of cannibalism clues, this mortality can not be attributable to the test item.

Clinical signs:

other:

Body weight:

other body weight observations

Remarks:

The body weight evolution of the animals remained normal during the study.

Gross pathology:

The macroscopic examination of the animals did not reveal treatment related changes.
The macroscopical examination of the animal that died during the study (unrelated to test item administration) revealed a stomach filled with air, a thinned wall with an orange coloration, associated with a cellular lysis of duodenum, jejunum, ileum, caecum and colon.

Other findings:

None

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Oral LD50 Cut-off (Females) = 5000 mg/kg bw.

Executive summary:

An acute oral toxicity study was conducted according to the OECD TG 423 and in compliance with GLP. The test item in olive oil was administered to a group of 6 8-weeks old female Sprague Dawley rats at the dose of 300 mg/kg body weight, then of 6 female Sprague Dawley rats at the dose of 2000 mg/kg body weight. The animals were observed for 14 days.

 

At 300 mg/kg bw, no mortality was noted in animals. No clinical signs related to the administration of the test item were observed during the study. The body weight evolution of the animals remained normal during the study. The macroscopic examination of the animals at the end of the study revealed a thinning of proventricular wall (3/6).

 

At 2000 mg/kg bw, one mortality was noted in an animal treated at the dose of 2000 mg/kg bw 6 days after the treatment (1/6). In the absence of clinical signs and the presence of cannibalism clues, this mortality can not be attributable to the test item. The macroscopical examination of this animal revealed a stomach filled with air, a thinned wall with an orange coloration, associated with a cellular lysis of duodenum, jejunum, ileum, caecum and colon.

No clinical signs related to the administration of the test item were observed during the study. The body weight evolution of the animals remained normal during the study. The macroscopic examination of the other animals did not reveal treatment related changes.

 

Oral LD₅₀ Cut-off (Females) = 5000 mg/kg bw.

 

Under the test conditions, the test item does not have to be classified according to the Regulation EC No. 1272/2008 (CLP) and to the Globally Harmonized System of classification and labelling of chemicals (GHS).

 

This study is acceptable and satisfies the requirements for acute oral toxicity testing (OECD 423) in the rats.