Registration Dossier

Administrative data

Endpoint:
short-term repeated dose toxicity: oral
Type of information:
experimental study
Adequacy of study:
key study
Study period:
August 13 - October 09, 2007
Reliability:
1 (reliable without restriction)
Cross-referenceopen allclose all
Reason / purpose:
reference to same study
Reason / purpose:
reference to other study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2008
Report Date:
2008

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 407 (Repeated Dose 28-Day Oral Toxicity in Rodents)
Deviations:
yes
Remarks:
see field below
Qualifier:
according to
Guideline:
EU Method B.7 (Repeated Dose (28 Days) Toxicity (Oral))
Deviations:
yes
Remarks:
see field below
Principles of method if other than guideline:
Functional observation results of males at 50 mg/kg/day (animal numbers 11-15) were not recorded. However, sufficient functional observation results were available for evaluation and the study integrity was not adversely affected.
GLP compliance:
yes
Limit test:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent

Test animals

Species:
rat
Strain:
Wistar
Sex:
male/female
Details on test animals and environmental conditions:
according to guideline

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
water
Details on oral exposure:
oral via gavage
Analytical verification of doses or concentrations:
yes
Details on analytical verification of doses or concentrations:
The concentrations analysed in the formulations of Group 2 (50 mg/kg bw/d), Group 3 (250 mg/kg bw/d) and Group 4 (1000 mg/kg bw/d) were in agreement with target concentrations (i.e. mean accuracies between 85% and 115%).
No test substance was detected in the Group 1 formulation (vehicle control).
The formulations of Group 2 and Group 4 were homogeneous (i.e. coefficient of variation ≤ 10%) (not determined for Group 3).
Duration of treatment / exposure:
28 days.
Frequency of treatment:
Once daily, 7 days per week, approximately the same time each day with a maximum of 4 hours difference between the earliest and latest dose.
Doses / concentrationsopen allclose all
Remarks:
Doses / Concentrations:
50 mg/kg bw/d
Basis:
actual ingested
Remarks:
Doses / Concentrations:
250 mg/kg bw/d
Basis:
actual ingested
Remarks:
Doses / Concentrations:
1000 mg/kg bw/d
Basis:
actual ingested
No. of animals per sex per dose:
5
Control animals:
yes, concurrent vehicle
Details on study design:
Doses are based on dose-range-finding

Examinations

Sacrifice and pathology:
Necropsy:
ORGAN WEIGHTS: Yes: Adrenal glands, Brain, Epididymides, Heart, Kidneys, Liver, Ovaries, Spleen, Testes, Thymus
Histopathology: yes
Gross Pathology: yes
Statistics:
- If the variables could be assumed to follow a normal distribution, the Dunnett-test1 (many-to-one t-test) based on a pooled variance estimate was applied for the comparison of the treated groups and the control groups for each sex.
- The Steel-test2 (many-to-one rank test) was applied when the data could not be assumed to follow a normal distribution.
- The exact Fisher-test3 was applied to frequency data.
All tests were two-sided and in all cases p < 0.05 was accepted as the lowest level of significance.

Results and discussion

Results of examinations

Clinical signs:
no effects observed
Mortality:
no mortality observed
Body weight and weight changes:
no effects observed
Food consumption and compound intake (if feeding study):
no effects observed
Food efficiency:
not examined
Water consumption and compound intake (if drinking water study):
not examined
Ophthalmological findings:
not examined
Haematological findings:
no effects observed
Clinical biochemistry findings:
no effects observed
Urinalysis findings:
no effects observed
Behaviour (functional findings):
no effects observed
Organ weight findings including organ / body weight ratios:
no effects observed
Gross pathological findings:
no effects observed
Histopathological findings: non-neoplastic:
no effects observed
Histopathological findings: neoplastic:
no effects observed

Effect levels

Dose descriptor:
NOAEL
Effect level:
1 000 mg/kg bw/day (actual dose received)
Sex:
male/female

Target system / organ toxicity

Critical effects observed:
not specified

Applicant's summary and conclusion

Conclusions:
Treatment up to 1000 mg/kg/day was well tolerated; no toxicologically relevant changes in clinical signs or functional observations were noted, and body weight and food intake appeared unaffected by treatment. Blood analyses revealed a few changes which were considered not to represent an adverse effect on organ function, taking into account their slight nature and the absence of corroborative morphological changes. At the end of the treatment period, these changes included lower relative lymphocyte counts and lower prothrombine time (PT), higher relative L- reticulocyte counts and mean corpuscular haemoglobin concentration (MCHC), in males at 50 and/or 250 mg/kg/day, and lower methaemoglobin levels in females at 1000 mg/kg/day. At the end of the recovery period, these changes consisted of lower relative L-reticulocyte counts, and higher relative M-reticulocyte counts and relative monocyte counts in males at 1000 mg/kg/day.
No treatment-related toxicologically significant changes were noted in any of the remaining parameters investigated in this study (i.e. macroscopic examination, organ weights, and microscopic examination).
NOAEL = 1000 mg/kg/day.