Registration Dossier

Administrative data

Endpoint:
acute toxicity: oral
Type of information:
experimental study
Adequacy of study:
key study
Study period:
Feb 2000
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2000
Report Date:
2000

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 423 (Acute Oral toxicity - Acute Toxic Class Method)
Deviations:
no
Qualifier:
according to
Guideline:
EU Method B.1 (Acute Toxicity (Oral))
Deviations:
no
GLP compliance:
yes
Test type:
acute toxic class method
Limit test:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent

Test animals

Species:
rat
Strain:
Wistar
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Harlan Winkelmann, Borchen, Germany
- Strain: Hsd Cpb:WU (SPF)
- Age at study initiation: 8-12 weeks
- Mean weight at study initiation: 273 g (males) or 178 g (females)
- Housing: in groups of 3 animals
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 +/- 2
- Humidity (%): 55 +/- 5
- Air changes (per hr): 15-20
- Photoperiod (hrs dark / hrs light): 12 / 12

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
other: polyethylene glycol 400
Details on oral exposure:
- Application volume: 10 mL/kg bw

- Rationale for the selection of the starting dose:
As described in the flow charts of Annex 2, OECD guideline 423, the starting dose level should be that which is most likely to produce mortality in
some of the dosed animals. Therefore, the limit dose 2000 mg/kg bw was chosen as starting dose.
Doses:
200 mg/kg (males and females), 2000 mg/kg (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: at least once daily (clinical signs, mortality) or once weekly (weight gain)
- Necropsy of survivors performed: yes
Statistics:
none

Results and discussion

Effect levels
Sex:
male/female
Dose descriptor:
other: LD50 cut-off
Effect level:
> 300 - < 500 mg/kg bw
Based on:
test mat.
Mortality:
All females died after administration of 2000 mg/kg bw. All males and females of the dose group 200 mg/kg bw survived
Clinical signs:
At 200 mg/kg bw the motility was decreased in both genders. In females additionally decreased reactivity, labored breathing, abdominal position (one animal) and temporary tremor (one animal) were observed. Additionally to the described signs, in females at 2000 mg/kg bw also staggering gait, increased salivation and temporary tachypnea occurred.
Body weight:
Body weight development was not affected at 200 and 2000 mg/kg bw..
Gross pathology:
In animals that died during the observation period a dark-red discoloration of the liver was detected. The animals sacrificed at the end of study showed no noticeable gross pathological findings.
Other findings:
none

Applicant's summary and conclusion

Interpretation of results:
harmful
Remarks:
Migrated information
Executive summary:

The acute oral toxicity of Imidoxim was moderate with a LD50 > 300 - < 500 mg/kg bw in rats (cut-off value) according to OECD TG 423. All females died after administration of 2000 mg/kg bw. All males and females of the dose group 200 mg/kg bw survived. Clinical signs were observed at 200 mg/kg bw and above in both genders. Body weight development was not affected until 2000 mg/kg bw. In animals that died during the observation period a dark-red discoloration of the liver was detected.