Registration Dossier

Administrative data

Endpoint:
acute toxicity: oral
Type of information:
experimental study
Adequacy of study:
key study
Study period:
From 26 March 2019 to 16 April 2019
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2019
Report Date:
2019

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 420 (Acute Oral Toxicity - Fixed Dose Method)
Deviations:
yes
Remarks:
The age of the animals was 6 to 8 weeks (beginning of treatment).The deviation does affect the validity of the study.
GLP compliance:
yes (incl. certificate)
Test type:
fixed dose procedure

Test material

Reference
Name:
Unnamed

Test animals

Species:
rat
Strain:
Wistar
Sex:
female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Envigo RMS B.V., Inc
- Age at study initiation: 7-8 weeks of age
- Weight at study initiation: females (160.1-172.1 g)
- Fasting period before study: Overnight
- Housing: 1-5 per cage (same sex and dose group)
- Diet (e.g. ad libitum): 2018C Teklad Global 18% protein rodent diet, ad libitum
- Water (e.g. ad libitum): tap water, ad libitum
- Acclimation period: 5 days


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 +/- 2
- Humidity (%): 45-65
- Artificial light: 6.00 a.m.-6.00 p.m.

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
corn oil
Remarks:
The test item was formulated at a concentration of 200 mg/mL in the vehicle and administered at a constant dose volume of 10 mL/kg body weight (2000 mg/kg body weight).
Details on oral exposure:
Dose administration was once orally by gavage (feeding needle). The volume administered did not exceed 10 mL/kg b.w.
Based on available information on the toxicity of the test item, 2000 mg/kg was chosen as the initial starting dose, since a severe toxicity which may necessitate humane euthanasia was not expected at this dose level.
Doses:
2000 mg/kg
No. of animals per sex per dose:
5 (2000 mg/kg); all animals tested were female.
Control animals:
no
Details on study design:
- Duration of clinical observation period following administration: 0.5, 1, 2, and 4 hours after dosing and daily thereafter for 14 days.
- Mortality and morbidity checks were made 3 times in the first 6 hours and then at least once daily
- Frequency of observations and weighing: Day 0 (prior to dosing), Day 7, and Day 14
- Necropsy of survivors performed: yes
- Animals were killed by carbon dioxide asphyxiation followed by cervical dislocation
- Other examinations performed: clinical signs, changes in the skin and fur, eyes and mucous membranes, and respiratory, circulatory, autonomic and central nervous system, and somatomotor activity and behavior pattern. Particular attention was directed to the observation of tremors, convulsions, salivation, diarrhea, lethargy, sleep and coma.

Results and discussion

Preliminary study:
A sighting study using one rat at the 2000 mg/kg dose level. In the absence of mortality or toxicity at a dose level of 2000 mg/kg, an additional group of 4 rats were dosed at 2000 mg/kg (n=5 total rats at 2000 mg/kg). There were no deaths during the study.
Effect levels
Key result
Sex:
female
Dose descriptor:
LD50
Effect level:
> 2 000 mg/kg bw
Based on:
test mat.
Remarks on result:
other: no deaths observed
Mortality:
No deaths observed.
Clinical signs:
Clinical signs observed were hunched posture and piloerection seen in all females dosed at the 2000 mg/kg dose level 30 minutes after dosing. Aniamls 2 to 5 additionally showed decrease activity 30 minutes after dosing. Additionally, partially closed eyes, lethargy, tiptoe gait, tremor of the head and noisy respiration was observed in animal 1 on the day of application. On day 2 this animal additionally showed ataxia and sunken flanks. Recovery of the animals, as judged by external appearance and behavior, was complete by Day 2 of animals 2-4 and on day 3 of animal 1.
Body weight:
All animals showed expected gains in body weight over the observation period.
Gross pathology:
Animal 1 and 2 showed enlarged genitals filled with clear liquid. In animal 3 a plethora of the thymus was observed while in animal 4 a plethora of the rectum bood vessels could be seen while the intestine of animal 4 was empty. No abnormalities were noted at necropsy in animal 5.
Other findings:
No other signs of toxicity.

Applicant's summary and conclusion

Interpretation of results:
Category 5 based on GHS criteria
Conclusions:
The acute oral median lethal dose (LD50) of the study substance in the female Wistar strain rat was estimated to be greater than 2000 mg/kg body weight (Globally Harmonized Classification System − Category 5).
Executive summary:

Acute oral toxicity of the study substance was assessed in the female Wistar strain rat.


Following a sighting test at a dose level of 2000 mg/kg b.w. in one female rat, a further group of four fasted females was given a single oral dose of  study substance, as a solution in corn oil, at a dose level of 2000 mg/kg body weight. Clinical signs and body weight development were monitored in all animals during the study. All animals were subjected to gross necropsy.


No deaths were observed. Clinical signs observed were hunched posture and piloerection seen in all females dosed at 2000 mg/kg. These signs were first noted approximately 30 minutes after dosing. Aniamls 2 to 5 additionally showed decrease activity 30 minutes after dosing. Additionally, partially closed eyes, lethargy, tiptoe gait, tremor of the head and noisy respiration was observed in animal 1 on the day of application. On day 1 animal 2 additionally showed ataxia and sunken flanks. Recovery of the animals, as judged by external appearance and behavior, was complete by Day 1 of animals 1 and 3-5 and on day 3 of animal 2. All animals showed expected gains in body weight. Animal 1 and 2 showed enlarged genitals filled with clear liquid. In animal 3 a plethora of the thymus was observed while in animal 4 a plethora of the rectum bood vessels was observed while the intestine of animal 4 was empty. No abnormalities were noted at necropsy in animal 5.


From these results it can be concluded that the acute oral median lethal dose (LD50) of the study substance in the female Wistar strain rat was estimated to be greater than 2000 mg/kg body weight.