1H-Imidazole, hydrobromide (1:1)

Endpoint summary

Description of key information

Acute oral toxicity: LD50 > 2000 mg/kg bw (OECD 423; GLP; female rats)

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:

2008-04-08 to 2008-04-23

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

2001-12-17

Deviations:

yes

Remarks:

rationale for the selection of the starting dose is missing; control group is used (not foreseen by the guideline)

GLP compliance:

yes (incl. QA statement)

Remarks:

signed 2007-02-15

Test type:

acute toxic class method

Limit test:

yes

Specific details on test material used for the study:

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: room temperature

Species:

rat

Strain:

Sprague-Dawley

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Elevage JANVIER (53940 Le Genest St Isle - France)
- Age at study initiation: 8 weeks old
- Weight at study initiation: 190 to 210 g
- Fasting period before study: day before treatment food was removed and restored 4 hours after test item administration
- Housing: three rats were kept in solid-bottomed clear polycarbonate cages with a stainless steel mesh lid; bedding: sawdust
- Diet (ad libitum)
- Water (ad libitum): drinking water (tap-water from public distribution system)
- Acclimation period: at least five days

ENVIRONMENTAL CONDITIONS
- Temperature: 19 °C - 23 °C
- Relative humidity: 42 % - 56 %
- Air exchanges: at least ten changes/hour
- Photoperiod (hrs dark / hrs light): 12/12

Route of administration:

oral: gavage

Vehicle:

other: distilled water

Details on oral exposure:

VEHICLE
- Batch no.: 100284201

MAXIMUM DOSE VOLUME APPLIED: 10 mL/kg bw (control group: 2 mL/kg bw)

DOSAGE PREPARATION:
The test item was freshly prepared in distilled water.

Doses:

2000 mg/kg bw

No. of animals per sex per dose:

Treatment group: 6 female rats (3 females/step)
Control group: 6 female rats

Control animals:

yes

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: during the acclimatisation period the animals were observed once a day. Furthermore, observations were carried out 30 minutes as well as 1, 3, and 4 hours after test item administration followed by daily administration.
The animals were weighed just before administeration of the test item (day 0) then on days 2, 7, and 14. Weight changes were calculated and recorded.
- Necropsy of survivors performed: yes, macroscopic examinations were carried out. Only those organs likely to be modified in cases of acute toxicity were examined. Those presenting macroscopic anomalies can be removed and preserved in view to microscopic examinations.

Statistics:

not applicable

Preliminary study:

not applicable

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

No mortality occurred during the study.

Clinical signs:

No clinical signs were observed during the acclimatisation period.
No clinical signs related to the administration of the test item were observed.

Body weight:

The body weight evolution of the treated and control animals remained normal throughout the study.

Gross pathology:

The macroscopical examination of the treated animals at the end of the study did not reveal treatment-related changes.

Interpretation of results:

GHS criteria not met

Conclusions:

LD50 (female rats) > 2000 mg/kg bw
According to the Regulation (EC) No 1272/2008 and subsequent adaptations, the substance is not acutely toxic via the oral route.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

discriminating dose

Value:

2 000 mg/kg bw

Justification for classification or non-classification

Acute oral toxicity

The substance is not acutely toxic via the oral route based on an acute oral toxicity test (OECD 423) and does not require classification according to Regulation (EC) No 1272/2008 and subsequent adaptations.

Specific target organ toxicant (STOT) - single exposure: oral

Reversible or irreversible adverse health effects were not observed immediately or after exposure in an acute oral toxicity test (OECD 423).Thus, the classification criteria as specific target organ toxicant (STOT) – single exposure, oral are not met and the substance does not require classification according to Regulation (EC) No 1272/2008 and subsequent adaptations.