2-ethyl-4-methylimidazole

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1985

Report date:

1985

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

Principles of method if other than guideline:

Three test groups (three doses) consisting of 5 animals/sex each were treated by single gavage application with an emulsion of the test substance. The animals were observed for mortality and for clinical symptoms of toxicity. At the end of the observation period of 14 days, the surviving animals were sacrificed for the purpose of necropsy; animals that died during the observations period also were subjected to necropsy.

GLP compliance:

no

Test type:

standard acute method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

2-ethyl-4-methylimidazole

EC Number:

213-234-5

EC Name:

2-ethyl-4-methylimidazole

Cas Number:

931-36-2

Molecular formula:

C6H10N2

IUPAC Name:

2-ethyl-4-methyl-1H-imidazole

Details on test material:

- Name of test material (as cited in study report): EMI-2,4 Fluessig

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Dr. K. Thomae GmbH, D-7950 Biberach, FRG
- Weight at study initiation: 170-189 g
- Fasting period before study: yes
- Housing: 5 animals per stainless steel mesh cage, type DK-III (Becker & Co., Castrop-Rauxel, FRG)
- Diet (e.g. ad libitum): Kliba-Labordiaet, FA, Klingentalmuehle AG, CH-4303 Kaiseraugst, Switserland, ad libitum
- Water (e.g. ad libitum): tap water ad libitum
- Acclimation period: at least 1 week

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 - 24
- Humidity (%): 30 - 70
- Photoperiod (hrs dark / hrs light): 12 / 12

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

CMC (carboxymethyl cellulose)

Remarks:

0.5 % emulsion

Details on oral exposure:

VEHICLE
- Concentration in vehicle (w/v): 10, 6.81, 4.64 mg/mL

MAXIMUM DOSE VOLUME APPLIED: 10 mL/kg

Doses:

1000, 681, 464 mg/kg bw

No. of animals per sex per dose:

5

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: recording of signs and symptoms several times on day of administration, at least once each workday. Check for moribund and dead animals twice each workday and once on holidays.
- Necropsy performed on died animals as well as sacrificed animals.
- Other examinations performed: clinical signs and body weight.

Results and discussion

Effect levels

Effect levels 1

Sex:

male

Dose descriptor:

LD50

Effect level:

ca. 754 mg/kg bw

Based on:

test mat.

Remarks on result:

other: Value from interpolation

Effect levels 2

Sex:

female

Dose descriptor:

LD50

Effect level:

ca. 681 mg/kg bw

Based on:

test mat.

Effect levels 3

Sex:

male/female

Dose descriptor:

LD50

Effect level:

ca. 731 mg/kg bw

Based on:

test mat.

Remarks on result:

other: value from interpolation

Mortality:

1000 mg/kg bw: all animals died within 1 day
681 mg/kg bw: 1 male and 2 female animals died within 1 day
464 mg/kg bw 1 female animal died within 1 day

Clinical signs:

other: Dyspnea, abnormal position. Apathy, staggering, tremors, twitching, convulsion of the jaws, fibr. contractions, intense yellow urine, piloerection, poor general state

Gross pathology:

Animals that died (male and female): general congestive hyperemia
Sacrificed animals (male and female): no abnormalies detected

Applicant's summary and conclusion

Interpretation of results:

Category 4 based on GHS criteria