Registration Dossier

Administrative data

Endpoint:
acute toxicity: oral
Type of information:
experimental study
Adequacy of study:
key study
Study period:
26 October 2016 to 13 February 2017
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2017
Report Date:
2017

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:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
liquid
Details on test material:
- Appearance/physical state: Light brown, slightly viscous, liquid
- Storage conditions: Room temperature in the dark

Test animals

Species:
rat
Strain:
Wistar
Remarks:
RccHan:WIST
Sex:
female
Details on test animals and environmental conditions:
ANIMAL INFORMATION
- Female Wistar (RccHan:WIST) strain rats were supplied by Envigo RMS (UK) Limited, Oxon, UK.
- On receipt the animals were randomly allocated to cages.
- The female animals were nulliparous and non-pregnant.
- After an acclimatisation period of at least five days, animals were selected at random and given a number unique within the study by indelible ink-marking on the tail and a number written on the cage card.
- At the start of the study the animals were 8 to 12 weeks of age.
- Body weight variation did not exceed ± 20 % of the mean body weight at the start of treatment.

ANIMAL CARE AND HUSBANDRY
- Animals were housed in groups of up to four in suspended solid-floor polypropylene cages furnished with woodflakes.
- With the exception of an overnight fast immediately before dosing, and for approximately 3 to 4 hours after dosing, free access to mains drinking water and food (2014C Teklad Global Rodent diet supplied by Envigo RMS (UK) Limited, Oxon, UK) was allowed throughout the study.
- Diet, drinking water and bedding were routinely analysed and were considered not to contain any contaminants that would reasonably be expected to affect the purpose or integrity of the study.
- Temperature and relative humidity were set to achieve limits of 19 to 25 °C and 30 to 70 % respectively.
- Rate of air exchange was at least 15 changes per hour.
- Lighting was controlled by a time switch to give 12 hours continuous light and 12 hours darkness.
- Animals were provided with environmental enrichment items that were considered not to contain any contaminant of a level that might have affected the purpose or integrity of the study.

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
unchanged (no vehicle)
Details on oral exposure:
TEST ITEM PREPARATION AND ANALYSIS
- The test item was used as supplied.
- For the initial 2000 mg/kg bw dose level, no purity correction was applied.
- For additional work (3390 mg/kg bw), a purity correction was applied to account for the active ingredient in the test item.
- Specific gravity was determined and used to calculate the appropriate dose volume for the required dose level.

STUDY DESIGN
- Using available information on the toxicity of the test item, the starting dose was chosen as 2000 mg/kg (see Annex 2 and Annex 3, attached).
- A single female animal was treated at a dose level of 2000 mg/kg bw (specific gravity 1.78; dose volume 1.128 mL/kg).
- In the absence of toxicity at a dose level of 2000 mg/kg bw, an additional four female animals were treated at a dose level of 2000 mg/kg bw (specific gravity 1.78; dose volume 1.128 mL/kg).

EXPOSURE TO TEST ITEM
- All animals were dosed once only by gavage, using a metal cannula attached to a graduated syringe.
- The volume administered to each animal was calculated according to the fasted body weight at the time of dosing.
- Treatment of animals was sequential.
- Sufficient time was allowed between each dose group to confirm the survival of the previously dosed animals.
- Clinical observations were made 0.5, 1, 2 and 4 hours after dosing and then daily for 14 days.
- Morbidity and mortality checks were made twice daily (early and late during normal working days and once daily at weekends and public holidays).
- Individual body weights were recorded on Day 0 (the day of dosing) and on Days 7 and 14.
- At the end of the observation period animals were killed by cervical dislocation.
- All animals were subjected to gross necropsy consisting of an external examination and opening of the abdominal and thoracic cavities. The appearance of any macroscopic abnormalities was recorded. No tissues were retained.

ADDITIONAL TEST
- The test was repeated with a purity correction applied.
- A single female animal was treated at a dose level of 3390 mg/kg bw (specific gravity 1.128; dose volume 3.01 mL/kg).
- In the absence of toxicity at a dose level of 3390 mg/kg bw, an additional four female animals were treated at a dose level of 3390 mg/kg bw (specific gravity 1.128; dose volume 3.01 mL/kg).
- The animals were dosed and observed as in the initial test.

DATA EVALUATION
- The test item was evaluated according to Annex 3 of the OECD Guidelines for Testing of Chemicals No 420 “Acute Oral Toxicity – Fixed Dose Method” (adopted 17 December 2001) as shown in the flow charts in Annex 2 and Annex 3 (attached).
- Evaluation of data included identification of the number of animals that died during the study (or that were killed for humane reasons) plus determination of the nature, severity, onset and duration of toxic effects. If possible, the signs of evident toxicity were described. Evident toxicity refers to the toxic effects of sufficient severity that administration of the next higher dose level could result in development of severe signs of toxicity and probable mortality. Effects on body weights and abnormalities noted at necropsy were also identified.
- Using the mortality data obtained, an estimate of the acute oral median lethal dose (LD50) of the test item was made.

MAJOR COMPUTERISED SYSTEMS
- Delta Controls: ORCAview
Doses:
Single dose
No. of animals per sex per dose:
- Five females at 2000 mg/kg bw (purity correction not applied)
- Five females at 3390 mg/kg (purity correction applied)
Control animals:
no

Results and discussion

Effect levels
Key result
Sex:
female
Dose descriptor:
LD50
Effect level:
> 2 000 mg/kg bw
Based on:
act. ingr.
Remarks on result:
other: equivalent to > 3390 mg/kg bw test item
Mortality:
- Individual mortality data are given in Appendix 1 for the initial test and Appendix 4 for the additional test (attached).
- No unscheduled animal deaths took place.
Clinical signs:
- Individual clinical observations are given in Appendix 1 for the initial test and Appendix 4 for the additional test (attached).
- No signs of systemic toxicity were noted during the observation period.
Body weight:
- Individual body weight and body weight changes are given in Appendix 2 for the initial test and Appendix 5 for the additional test (attached).
- All animals showed expected gains in body weight over the observation period.
Gross pathology:
- Individual necropsy findings are given in Appendix 3 for the initial test and Appendix 6 for the additional test (attached).
- No abnormalities were noted at necropsy.

Applicant's summary and conclusion

Interpretation of results:
GHS criteria not met
Conclusions:
The acute oral median lethal dose (LD50) of the test item in the female Wistar strain rat was found to be > 3390 mg/kg bw (equivalent to > 2000 mg active ingredient/kg bw).
Executive summary:

GUIDELINE

The study was performed to assess acute oral toxicity of the test item in the Wistar strain rat in compliance with the OECD Guideline for Testing of Chemicals No 420 “Acute Oral Toxicity – Fixed Dose Method” (2001) and Method B.1 bis Acute Toxicity (Oral) of Commission Regulation (EC) No 440/2008.

 

METHODS

Initial work (five animals) was conducted at a dose level of 2000 mg/kg bw without a purity correction being applied. Therefore, at the request of the sponsor, additional work was performed with a purity correction applied. Following a sighting test at dose level of 3390 mg/kg bw (equivalent to 2000 mg active ingredient/kg bw), an additional four fasted female animals were given a single oral dose of test item at a dose level of 3390 mg/kg bw. Clinical signs and body weight development were monitored during the study. All animals were subjected to gross necropsy.

 

RESULTS

No animal deaths took place during the study and clinical observations resulted in no reports of systemic toxicity. All animals showed expected gains in body weight and no abnormalities were noted at necropsy.

 

CONCLUSION

The acute oral median lethal dose (LD50) of the test item in the female Wistar strain rat was found to be > 3390 mg/kg bw (equivalent to > 2000 mg active ingredient/kg bw).