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Toxicological information

Acute Toxicity: oral

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Administrative data

Endpoint:
acute toxicity: oral
Type of information:
experimental study
Adequacy of study:
key study
Study period:
4 December 2012 to 27 December 2012
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Study conducted to GLP in compliance with agreed protocols, with no or minor deviations from standard test guidelines and/or minor methodological deficiencies, which do not affect the quality of the relevant results.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2013
Report Date:
2013

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 420 (Acute Oral Toxicity - Fixed Dose Method)
Deviations:
no
Qualifier:
according to
Guideline:
EU Method B.1 bis (Acute Oral Toxicity - Fixed Dose Procedure)
Deviations:
no
GLP compliance:
yes (incl. certificate)
Test type:
fixed dose procedure
Limit test:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
other: solid (unspecified)
Details on test material:
- Appearance: pale brown solid
- Storage conditions: room temperature in the dark

Test animals

Species:
rat
Strain:
Wistar
Sex:
female
Details on test animals and environmental conditions:
TEST ANIMALS
- Age at study initiation: 8 - 12 weeks.
- Weight at study initiation: 160 - 175 g. The bodyweight variation did not exceed ± 20 % of the initial bodyweights.
- Fasting period before study: yes (animals were fasted overnight immediately before dosing and for approximately three to four hours after dosing).
- Housing: animals were housed in groups up to four in suspended solid-floor polypropylene cages furnished with wood flakes.
- Diet: provided ad libitum.
- Water: mains drinking water, ad libitum.
- Acclimation period: at least 5 days.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19 - 25 °C
- Humidity (%): 30 - 70 %
- Air changes (per hr): at least 15 air changes per hour.
- Photoperiod (hrs dark / hrs light): 12 hours light / 12 hours dark.

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
DMSO
Details on oral exposure:
PREPARATION OF DOSING FORMULATIONS
The test material was freeze dried using liquid nitrogen, ground to a powder and then freshly prepared, as required, as a solution in dimethyl sulphoxide DMSO. To aid preparation, the formulation was warmed in a water bath at 85 °C for 1 hour. The formulation was allowed to cool before dosing. DMSO was used because the test material did not dissolve/suitably suspend in distilled water/arachis oil BP.

The test material was formulated within 2 hours of being applied to the test system.

VEHICLE
- Concentration in vehicle: 200 mg/mL (2000 mg/kg dose); 30 mg/mL (300 mg/kg dose).

MAXIMUM DOSE VOLUME APPLIED: 10 mL/kg
The volume administered to each animal was calculated according to the fasted bodyweight at the time of dosing.
Doses:
2000 mg/kg bw (sighting test)
300 mg/kg bw (main test)
No. of animals per sex per dose:
1 (sighting test)
5 (main test)
Control animals:
no
Details on study design:
- Study schedule: a single animal was dosed at 2000 mg/kg. Due to mortality at this dose level, an additional group of animals was treated at 300 mg/kg. Treatment of the animals was sequential; sufficient time was allowed between each dose level to confirm survival of the previously dosed animals.
- Duration of observation period following administration: 14 days
- Frequency of observations: clinical observations were made ½, 1, 2 and 4 hours after dosing and then daily thereafter. Morbidity and mortality checks were made twice daily.
- Frequency of weighing: individual bodyweights were recorded on Day 0 (the day of dosing) and on Days 7 and 14 or at death.
- Necropsy of survivors performed: yes (this consisted of an external examination and opening of the abdominal and thoracic cavities). The appearance of any macroscopic abnormalities was recorded.
Statistics:
An estimate of the LD50 value was made according to the observed mortality rate.

Results and discussion

Effect levelsopen allclose all
Sex:
female
Dose descriptor:
LD50
Effect level:
300 - 2 000 mg/kg bw
Based on:
test mat.
Sex:
female
Dose descriptor:
discriminating dose
Effect level:
300 mg/kg bw
Based on:
test mat.
Mortality:
The animal dosed at 2000 mg/kg was killed for humane reasons, eight days after dosing, due to the occurrence of clinical signs of toxicity that exceeded the severity limit set forth in the UK Home Office Project Licence.
None of the animals dosed at 300 mg/kg died during the study.
Clinical signs:
Signs of systemic toxicity noted on the animal dosed at 2000 mg/kg included hunched posture, pilo-erection, tiptoe gait, emaciation, dehydration, and palor of the extremities and hypothermia.
In the group dosed at 300 mg/kg clinical signs included hunched posture, which was noted in all animals. Ataxia was also noted in one animal. All animals appeared normal one day after dosing.
Body weight:
The animal dosed at 2000 mg/kg lost weight during the study, as weight loss of 27 g was observed in week 1.
Animals dosed at 300 mg/kg all showed expected gains in bodyweight over the observation period.
Gross pathology:
Pale liver and kidneys were noted at necropsy in the animal dosed at 2000 mg/kg.
No abnormalities were noted at necropsy of animals dosed at 300 mg/kg.

Applicant's summary and conclusion

Interpretation of results:
Toxicity Category IV
Remarks:
Migrated information Criteria used for interpretation of results: EU
Conclusions:
Under the conditions of the study the acute oral LD50 of the test material in the female Wistar strain rat was estimated to be in the range of 300 to 2000 mg/kg bw.
Executive summary:

The acute oral toxicity of the test material was investigated in a GLP study which was conducted in accordance with the standardised guidelines OECD 420 and EU Method B.1 bis, following the fixed dose method.

Following a sighting test in a single animal dosed 2000 mg/kg bw, a group of five fasted females was given a single oral dose of test material, as a solution in dimethyl sulphoxide, at a dose level of 300 mg/kg bw. Clinical signs and bodyweight development were monitored during the study and all animals were subjected to gross necropsy at study termination on day 14.

The animal treated at 2000 mg/kg was killed for human reasons, eight days after dosing, due to the occurrence of clinical signs of toxicity that exceeded the severity limit set forth in the UK Home Office Project Licence. There were no deaths in the group dosed at 300 mg/kg.

Signs of systemic toxicity noted in the animals treated at 2000 mg/kg were hunched posture, pilo-erection, tiptoe gait, emaciation, dehydration, pallor of the extremities and hypothermia. Ataxia and/or hunched posture were noted in animals treated at 300 mg/kg.

Pale liver and kidneys were noted at necropsy of the animal treated at 2000 mg/kg. No abnormalities were noted a necropsy of animals treated at a dose level of 300 mg/kg.

Under the conditions of the study the acute oral LD50 of the test material in the female Wistar strain rat was estimated to be in the range of 300 to 2000 mg/kg bw, and the discriminating dose was considered to be 300 mg/kg bw.