Niobium hydride

Repeated dose toxicity: oral

Administrative data

Endpoint:

short-term repeated dose toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

03 June 2020 to 16 July 2021

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2021

Report date:

2021

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 422 (Combined Repeated Dose Toxicity Study with the Reproduction / Developmental Toxicity Screening Test)

Version / remarks:

2016

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

other: EPA OPPTS 870.3650

Version / remarks:

Combined Repeated Dose Toxicity Study with the Reproduction/Developmental Toxicity Screening Test, 2000.

Deviations:

no

GLP compliance:

yes

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Niobium hydride

EC Number:

237-769-9

EC Name:

Niobium hydride

Cas Number:

13981-86-7

Molecular formula:

HNb

IUPAC Name:

niobium(1+) hydride

Test material form:

solid

Remarks:

Silver grey solid

Details on test material:

- Storage conditions: At room temperature.

Test animals

Species:

rat

Strain:

Wistar

Remarks:

Crl: WI(Han)

Details on species / strain selection:

The Wistar Han rat was chosen as the animal model for this study as it is an accepted rodent species for toxicity testing by regulatory agencies. The test facility has general and reproduction/developmental historical data in this species from the same strain and source. This animal model has been proven to be susceptible to the effects of reproductive toxicants.
The total number of animals used in this study was considered to be the minimum required to properly characterise the effects of the test material. This study has been designed such that it does not require an unnecessary number of animals to accomplish its objectives.
At this time, studies in laboratory animals provide the best available basis for extrapolation to humans and are required to support regulatory submissions. Acceptable models which do not use live animals currently do not exist.

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Females nulliparous and non-pregnant: Yes
- Age at study initiation: At initiation of dosing, males were 10 - 11 weeks old and females were 13 - 14 weeks old.
- Weight at study initiation: Males weighed between 270 and 308 g and females weighed between 200 and 240 g.
- Housing: On arrival and following the pretest (females only) and pre-mating period, animals were group housed (up to 5 animals of the same sex and same dosing group together) in polycarbonate cages (Macrolon, MIV type, height 18 cm). During the mating phase, males and females were cohabitated on a 1:1 basis in Macrolon plastic cages (MIII type, height 18 cm).
During the post-mating phase, males were housed in their home cage (Macrolon plastic cages, MIV type, height 18 cm) with a maximum of 5 males/cage. Females were individually housed in Macrolon plastic cages (MIII type, height 18 cm). During the lactation phase, females were housed in Macrolon plastic cages (MIII type, height 18 cm). Pups were housed with the dam, except during locomotor activity monitoring of the dams, when the pups were kept warm in their home cage using bottles filled with warm water. During locomotor activity monitoring, animals were housed individually in a Hi-temp polycarbonate cage (dimensions: 48.3 x 26.7 x 20.3 cm) without cage-enrichment, bedding material, food and water. The cages contained appropriate bedding and were equipped with water bottles. The rooms in which the animals were kept were documented in the study records. Animals were separated during designated procedures/activities. Each cage was clearly labelled with a colour-coded cage card indicating Test Facility Study No., group, animal number(s), and sex.
- Diet: Ad libitum throughout the study, except during designated procedures.
- Water: Freely available to each animal via water bottles.
- Acclimation period: The animals were allowed to acclimate to the Test Facility toxicology accommodation for 7 days prior to start of the pretest period (females) or 7 days before the commencement of dosing (males).

DETAILS OF FOOD AND WATER QUALITY:
- Food: Pelleted rodent diet was provided ad libitum throughout the study, except during designated procedures. During motor activity measurements, animals had no access to food for a maximum of 2 hours. The feed was analysed by the supplier for nutritional components and environmental contaminants. Results of the analysis were provided by the supplier and are on file at the Test Facility. It is considered that there were no known contaminants in the feed that would interfere with the objectives of the study
- Water: Municipal tap water was freely available to each animal via water bottles. During motor activity measurements, animals had no access to water for a maximum of 2 hours. Periodic analysis of the water was performed, and results of these analyses are on file at the Test Facility. It is considered that there were no known contaminants in the water that would interfere with the objectives of the study.

ENVIRONMENTAL CONDITIONS
- Temperature: Target temperatures of 18 to 24 °C was maintained. The actual daily mean temperature during the study period was 19 to 21 °C.
- Humidity: Target relative target humidity of 40 to 70 % was maintained. The actual daily mean relative humidity of 51 to 79 %. The humidity values that were outside the targeted range occurred for 33 days and were without a noticeable effect on the clinical condition of the animals or on the outcome of the study.
- Air changes: Ten or greater air changes per hour with 100 % fresh air (no air recirculation) were maintained in the animal rooms.
- Photoperiod: A 12-hour light/ 12-hour dark cycle was maintained.

Administration / exposure

Route of administration:

oral: gavage

Details on route of administration:

- The dose volume for each animal was based on the most recent body weight measurement.
- The doses were given using a plastic feeding tube.
- The dosing formulations were stirred continuously during dose administration.
- A dose control system (DCS) was used as additional check to verify the dosing procedure according to Standard Operating Procedures.
- Dose volume: 5 mL/kg
- Dose concentration:
100 mg/kg /day group: 20 mg/mL
300 mg/kg /day group: 60 mg/mL
1 000 mg/kg /day group: 200 mg/mL

Vehicle:

corn oil

Remarks:

Specific gravity 0.92.

Details on oral exposure:

PREPARATION OF DOSING SOLUTIONS:
- Test material dosing formulations (w/w) were homogenised to visually acceptable levels at appropriate concentrations to meet dose level requirements. The dosing formulations were prepared daily as a suspension and dosed within 2 hours after adding the vehicle to the test material. Formulations were prepared protected from light.
- Test material dosing formulations were kept at room temperature until dosing. The dosing formulations and vehicle were continuously stirred until and during dosing. Adjustment was made for specific gravity of the vehicle (adjustment factor 0.92). No correction was made for the purity/composition of the test material. Any residual volumes were discarded.

VEHICLE
- Justification for use and choice of vehicle: Trial preparations were performed to select the suitable vehicle and to establish a suitable formulation procedure. These trials were not performed as part of this study and these preparations were not used for dosing.

Analytical verification of doses or concentrations:

no

Details on analytical verification of doses or concentrations:

Analysis of test material in vehicle for concentration, homogeneity, and stability was not performed, as no feasible analytical method was available. In theory metal ions, such as in the test material, could be analysed by ICP-MS, if the test material could be dissolved in an aqueous solution. However, the test material did not dissolve in aqueous solutions, nor did it dissolve in concentrated nitric acid, nitric acid/hydrogen peroxide or concentrated hydrochloric acid. Moreover, a visibly stable suspension could be prepared only in corn oil for the administration to rats. A corn oil formulation could not be dissolved in aqueous solutions and therefore, no quantitative analysis was performed.
During the current study, the test material dosing formulations were prepared with corn oil. The test material is a transition metal hydride. It is binary metal hydride, which is known not to dissolve in any solvent. As the substance is a metal compound and does not dissolve in concentrated nitric acid, nitric acid/hydrogen peroxide or concentrated hydrochloric acid, the substance was also not expected to react with any oil-like substance like corn oil and thus was expected to be stable in corn oil for the period from formulation till administration.
In addition, to limit the impact, the test material preparations were performed with approved procedures and documented in detail. Preparations were visually inspected for homogeneity prior to use and all preparations were used within 2 hours after completion of the preparation of the test material. Additionally, test material formulations were prepared protected from light. This GLP exception was therefore considered as being minor with no impact on the outcomes and the integrity and the achievement of the objective of the study.

Duration of treatment / exposure:

- A minimum of 28 days.
- Males were treated for 29 days, up to and including the day before scheduled necropsy. This included a minimum of 14 days prior to mating and during the mating period. Females that delivered were treated for 50 - 56 days, i.e. 14 days prior to mating (with the objective to cover at least two complete oestrous cycles), the variable time to conception, the duration of pregnancy and at least 13 days after delivery, up to and including the day before scheduled necropsy. Females which failed to deliver or had a total litter loss were treated for 41 - 48 days.
The first day of dosing was designated as Day 1.

Frequency of treatment:

Once daily

Doses / concentrations

Doses / concentrations 1

Dose / conc.:

100 mg/kg bw/day (nominal)

Doses / concentrations 2

Dose / conc.:

300 mg/kg bw/day (nominal)

Doses / concentrations 3

Dose / conc.:

1 000 mg/kg bw/day (nominal)

No. of animals per sex per dose:

Five per sex per dose.

Control animals:

yes, concurrent vehicle

Details on study design:

- Dose selection rationale: The oral route of administration was selected this is a possible route of human exposure during manufacture, handling or use of the test material. The dose levels were selected based on the results of a 10-Day Dose Range Finder with oral administration of the test material in rats (Test Facility Reference No. 20236631), which identified no dose-limiting adversity up to the limit dose of 1 000 mg/kg bw/day. Therefore, the highest dose was selected based on the OECD 422 guideline limit dose and the intermediate and low dose were selected in an attempt to produce graded responses to the test material.
- Rationale for animal assignment: Animals were randomly assigned to groups at arrival. Males and females were randomised separately. As this study was a combined reproductive and repeated dose toxicity test, a total of 40 females were selected at randomisation before initiation of the pretest phase. Females were evaluated for regular oestrous cyclicity before allocation. Any selected female classified as not having regular oestrous cycles during the pretest phase (6 females in total) was replaced before initiation of dosing by one of the 8 additional females having regular oestrous cycles. A total of 40 females with regular oestrous cycles continued in the study. The eight supernumerary or irregularly cycling females were removed from the study, and their oestrous cycle results were kept in the raw data but not reported.
- Fasting period before blood sampling for clinical biochemistry: F0-males were fasted overnight with a maximum of 24 hours before blood sampling, but water was available. F0- females were not fasted overnight.

Examinations

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: Twice daily, in the morning and at the end of the working day. Animals were not removed from the cage during observation, unless necessary for identification or confirmation of possible findings.
- Cage side observations checked: Throughout the study, animals were observed for general health/mortality and moribundity.

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: Clinical observations were performed once daily, beginning during the first administration of the test material and lasting throughout the dosing periods up to the day prior to necropsy. During the dosing period, these observations were performed after dosing at no specific time point, but within a similar time period after dosing for the respective animals (no peak effect of occurrence of clinical signs was observed in the dose range finder. The time of onset, grade and duration of any observed sign was recorded. Signs were graded for severity and the maximum grade was predefined at 3 or 4. Grades were coded as slight (grade 1), moderate (grade 2), severe (grade 3) and very severe (grade 4). For certain signs, only its presence (grade 1) or absence (grade 0) was scored. In the data tables, the scored grades were reported, as well as the percentage of animals affected in summary tables. Clinical observations were conducted in a standard arena beginning before the first administration of the test material and then once weekly throughout treatment. These observations were conducted after dosing.

BODY WEIGHT: Yes
- Time schedule for examinations: Animals were weighed individually on the first day of treatment (prior to dosing), and weekly thereafter. Mated females were weighed on days 0, 4, 7, 11, 14, 17, and 20 post-coitum and during lactation on PND 1, 4, 7, and 13. A terminal weight was recorded on the day of scheduled necropsy.

FOOD CONSUMPTION:
- Food consumption was quantitatively measured weekly, except for males and females which were housed together for mating and for females without evidence of mating. Food consumption of mated females was measured on days 0, 4, 7, 11, 14, 17, and 20 post-coitum and during lactation on PND 1, 4, 7, and 13.

FOOD EFFICIENCY: No

WATER CONSUMPTION: Yes
- Time schedule for examinations: Subjective appraisal was maintained during the study, but no quantitative investigation was introduced as no effect was suspected. Water consumption was monitored on regular basis throughout the study by visual inspection of the water bottles.

OPHTHALMOSCOPIC EXAMINATION: No

HAEMATOLOGY: Yes
- Time schedule for collection of blood: Blood of F0-animals was collected on the day of scheduled necropsy. Samples were collected, between 7.00 and 10.30 a.m., from the retro-orbital sinus in the animal facility. Due to clotting of non-serum samples of individual animals, additional blood samples were obtained in the necropsy room. After collection all samples were transferred to the appropriate laboratory for analysis.
- Anaesthetic used for blood collection: Yes under anesthesia using isoflurane.
- Animals fasted: F0-males were fasted overnight with a maximum of 24 hours before blood sampling, but water was available. F0-females were not fasted overnight.
- Parameters checked: Blood samples at a target volume of 0.5 mL were collected into tubes containing K3-EDTA as anticoagulant. Samples were analysed for: White blood cell (WBC), Neutrophils (absolute), Lymphocytes (absolute), Monocytes (absolute), Eosinophils (absolute), Basophils (absolute), Large unstained cells (LUC) (absolute), Red blood cell (RBC), Reticulocytes (absolute), Red blood cell distribution width gated (RDWG), Haemoglobin, Haematocrit, Mean corpuscular volume (MCV), Mean corpuscular haemoglobin (MCH), Mean corpuscular haemoglobin concentration (MCHC), Platelets. A blood smear was prepared from each haematology sample. Blood smears were labelled, stained, and stored. Blood smears were evaluated when required to confirm analyser results.
- Coagulation: Blood samples at a target volume of 0.45 mL were collected into tubes containing Citrate as anticoagulant. Samples were processed for plasma, and plasma was analysed for the parameter Prothrombin time (PT)

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: Blood of F0-animals was collected on the day of scheduled necropsy. Samples were collected, between 7.00 and 10.30 a.m., from the retro-orbital sinus in the animal facility. Due to clotting of non-serum samples of individual animals, additional blood samples were obtained in the necropsy room. After collection all samples were transferred to the appropriate laboratory for analysis.
- Animals fasted: F0-males were fasted overnight with a maximum of 24 hours before blood sampling, but water was available. F0-females were not fasted overnight.
- Parameters checked: Alanine aminotransferase (ALT), Aspartate aminotransferase (AST), Glucose Alkaline phosphatase (ALP), Total protein, Albumin, Total bilirubin, Bile acids, Urea, Glucose, Creatinine, Cholesterol, Sodium, Potassium, Chloride, Calcium, Inorganic phosphate (Inorg. Phos).

PLASMA/SERUM HORMONES/LIPIDS: Yes
- Time of blood sample collection: Blood of F0-animals was collected on the day of scheduled necropsy. Samples were collected, between 7.00 and 10.30 a.m., from the retro-orbital sinus in the animal facility. Due to clotting of non-serum samples of individual animals, additional blood samples were obtained in the necropsy room. After collection all samples were transferred to the appropriate laboratory for analysis.
- Animals fasted: F0-males were fasted overnight with a maximum of 24 hours before blood sampling, but water was available. F0-females were not fasted overnight.
- Blood samples at a target volume of 1.0 mL (F0- animals), 0.5 mL (pooled PND 4 pups) and 1.0 mL (PND 14-16 pups) were collected into tubes without anticoagulant. Blood samples were processed for serum, and serum was analysed for the parameters. Blood samples were processed for serum, and serum was analysed for total Thyroxine (T4). For the F0-generation, assessment of T4 (females) and Thyroid Stimulating Hormone (TSH; both sexes) was considered not relevant because no treatment-related changes in T4 were noted in F0-males, no adverse effects on thyroid histopathology and no treatment related changes in thyroid weight were recorded. Assessment of T4 for PND 4 pups and TSH for PND 14 - 16 pups was considered not relevant because no treatment-related changes in T4 were noted in pups at PND 14 - 16.
Serum samples retained for possible future analysis were maintained by the Test Facility in the freezer (≤-75 °C). Under these storage conditions, samples are stable for 6 months. Any remaining sample were discarded at finalisation.

URINALYSIS: No

NEUROBEHAVIOURAL EXAMINATION: Yes
- Time schedule for examinations:
These tests were performed after dosing, after completion of clinical observations. Functional tests were performed on the selected 5 males during Week 4 of treatment and the selected 5 females during the last week of lactation (i.e. PND 6 - 13).
- Dose groups that were examined: 5 males and 5 females.
- Battery of functions tested: The following tests were performed: Hearing ability (HEARING) (Score 0 = normal/ present, score 1 = abnormal/ absent). Pupillary reflex (PUPIL L/R) (Score 0 = normal/ present, score 1 = abnormal/ absent). Static righting reflex (STATIC R) (Score 0 = normal/ present, score 1 = abnormal/ absent). Fore- and hind-limb grip strength, recorded as the mean of three measurements per animal. Locomotor activity (recording period: 1-hour under normal laboratory light conditions, using a computerised monitoring system). Total movements and ambulations were reported. Ambulations represent movements characterised by a relocation of the entire body position like walking, whereas total movements represent all movements made by the animals, including ambulations but also smaller or more fine movements like grooming, weaving or movements of the head.

IMMUNOLOGY: No

Sacrifice and pathology:

GROSS PATHOLOGY: Yes
- Animals surviving until scheduled euthanasia were weighed, and deeply anesthetised using isoflurane and subsequently exsanguinated and subjected to a full post mortem examination.
Scheduled necropsies were conducted on the following days: Males (which sired and failed to sire): Following completion of the mating period (a minimum of 28 days of administration). Females which delivered: PND 14 - 16. Females which failed to deliver (Nos. 43, 65, 64, 70, 76 and 77): With evidence of mating: Post-coitum Day 25 - 27. All males surviving to scheduled necropsy were fasted overnight with a maximum of 24 hours before necropsy. Water was available. F0-females were not fasted.
- All animals were subjected to a full post mortem examination, with special attention being paid to the reproductive organs.
- Necropsy procedures were performed by qualified personnel with appropriate training and experience in animal anatomy and gross pathology. A veterinary pathologist, or other suitably qualified person, was available. The numbers of former implantation sites were recorded for all paired females. In case no macroscopically visible implantation sites were present, non-gravid uteri were stained using the Salewski technique in order to detect any former implantation sites and the number of corpora lutea was recorded in addition.

Organ Weights – F0-Generation
- The organs identified below were weighed at necropsy for all scheduled euthanasia animals. Paired organs were weighed together. In the event of gross abnormalities, the weight of the aberrant organ was taken and recorded in the raw data. Organ to body weight ratios (using the terminal body weight) were calculated.
- Brain, Cervix (weighed together with the uterus), Epididymis (paired organ weight), Gland, adrenal (paired organ weight), Gland, coagulation (paired organ weight; weighed together with the seminal vesicles), Gland, parathyroid (weighed together with the thyroid), Gland, prostate, Gland, seminal vesicle (paired organ weight), Gland, thyroid (paired organ weight), Heart, Kidney (paired organ weight), Liver, Ovaries (paired organ weight), Spleen, Testes (paired organ weight), Thymus, Uterus.

- Organs Weighed at Necropsy for all Remaining Animals (incl. Males that Failed to Sire and Females that Failed to Deliver): Epididymis (paired organ weight), Gland, coagulationa, (weighed together with seminal vesicles), Gland, parathyroid (weighed together with the thyroid), Gland, prostate, Gland, seminal vesicle (paired organ weight), Gland, thyroid (paired organ weigth), Testes (paired organ weight).

HISTOPATHOLOGY: Yes
- Representative samples of the tissues identified below were collected from all animals and preserved in 10 % neutral buffered formalin (neutral phosphate buffered 4 % formaldehyde solution) unless otherwise indicated. Tissue Collection and Preservation for all Selected Animals:
Animal identification
Artery, aorta
Body cavity, nasopharynx
Bone marrow
Bone, femur
Bone, sternum
Brain (eight levels)
Cervix
Epididymides (preserved in modified Davidson's fixative and transferred to formalin after fixation for at least 24 h).
Esophagus
Eye (preserved in modified Davidson's fixative and transferred to formalin after fixation for at least 24 h).
Gland, adrenal
Gland, coagulation
Gland, Harderian (preserved in modified Davidson's fixative and transferred to formalin after fixation for at least 24 h. Only collected if present in the routine section of the eye. Part of the optic nerve attached to the eye was fixed in Modified Davidsons’s fixative. The remaining part of the optic nerve was placed in formalin).
Gland, lacrimal
Gland, mammary
Gland, parathyroid (Only collected if present in the routine section of the thyroid).
Gland, pituitary
Gland, prostate
Gland, salivary
Gland, seminal vesicle
Gland, thyroid
Gross lesions/masses
Gut-associated lymphoid tissue
Heart
Kidney
Large intestine, cecum
Large intestine, colon
Large intestine, rectum
Larynx
Liver
Lung
Lymph node (mandibular and mesenteric site)
Muscle, skeletal
Nerve, optic (Only collected if present in the routine section of the eye. Part of the optic nerve attached to the eye was fixed in Modified Davidsons’s fixative. The remaining part of the optic nerve was placed in formalin).
Nerve, sciatic
Ovaries
Pancreas
Skin
Small intestine, duodenum
Small intestine, ileum
Small intestine, jejunum
Spinal cord
Spleen
Stomach
Testes (Preserved in modified Davidson’s fixative and transferred to formalin after fixation for at least 24 hours).
Thymus
Tongue
Trachea
Urinary bladder
Uterus
Vagina

- Tissues that were supposed to be microscopically evaluated per protocol but were not available on the slide (and therefore not evaluated) are listed in Individual Animal Data of the pathology report as not present. These missing tissues did not affect the outcome or interpretation of the pathology portion of the study because sufficient data was available.
Tissue Collection and Preservation for all Remaining Animals (incl. Males that Failed to Sire and Females that Failed to Deliver):
Animal identification
Cervix
Epididymis (Preserved in modified Davidson’s fixative and transferred to formalin after fixation for at least 24 hours).
Gland, coagulation
Gland, mammary
Gland, parathyroid (Only collected if present in the routine section of the thyroid).
Gland, pituitary
Gland, prostate
Gland, seminal vesicle
Gland, thyroid
Gross lesions/masses
Ovaries
Testes (Preserved in modified Davidson’s fixative and transferred to formalin after fixation for at least 24 hours).
Uterus
Vagina

- The following tissues were embedded in paraffin, sectioned, mounted on glass slides, and stained with haematoxylin and eosin for selected animals:
Males that failed to sire (except for males which were selected) and females that failed to deliver pups: Tissues identified above (except animal identification, aorta, nasopharynx, esophagus, harderian gland, lacrimal gland, salivary gland, larynx, optic nerve, pancreas, skin and tongue).
Remaining animals: Gross lesions/ masses.

- Histopathology – F0-Generation: All tissues as defined under Histology – F0-Generation were examined by a board-certified toxicological pathologist with training and experience in laboratory animal pathology. A peer review on the histopathology data was performed by a second pathologist.

Other examinations:

Parental Variables
Body Weight Gains: Calculated against the body weight on Day 1 (pre-mating and lactation periods) or Day 0 (post-coitum period).
Relative Food Consumption: Calculated against the body weight for scheduled intervals.
Organ Weight Relative to Body Weight: Calculated against the terminal body weight.

Statistics:

See below.

Results and discussion

Results of examinations

Clinical signs:

effects observed, non-treatment-related

Description (incidence and severity):

No treatment-related clinical signs were noted during daily detailed clinical observations.
Hunched posture was noted on multiple days (Days 24 - 27) during the last week of treatment in one male treated at 1 000 mg/kg/day, in one female at 300 mg/kg over Days 29 - 41 of treatment and in several females at 1 000 mg/kg/day over Days 20 - 41 of treatment. As clinical signs were transient and occurred in a few animals only, these were considered incidental and not toxicologically relevant.
Salivation seen incidentally after dosing among some animals among all dose groups was considered not toxicologically relevant, taking into account the nature and minor severity of the effect and its time of occurrence (i.e. after dosing). This sign was considered to be a physiological response rather than a sign of systemic toxicity.
Any other clinical signs that were noted during the treatment period (i.e. scabs, wounds, alopecia and piloerection) occurred within the range of background findings to be expected for rats of this age and strain which are housed and treated under the conditions in this study and did not show any apparent dose-related trend. At the incidence observed, these were considered to be unrelated to treatment with the test material.

Mortality:

no mortality observed

Description (incidence):

No mortality occurred during the study period.

Body weight and weight changes:

no effects observed

Description (incidence and severity):

No test material-related changes in body weights and body weight gain were observed in males and females up to 1 000 mg/kg/day.
The slightly lower body weight (gain) on post-coitum Day 20 in females at 1 000 mg/kg/day was attributed to two females with implantation sites only.

Food consumption and compound intake (if feeding study):

not examined

Food efficiency:

not examined

Water consumption and compound intake (if drinking water study):

not examined

Ophthalmological findings:

not examined

Haematological findings:

effects observed, non-treatment-related

Description (incidence and severity):

A lower haemoglobin concentration was noted in females treated at 300 and 1 000 mg/kg/day (0.94x and 0.93x of control, and 4/5 and 4/5 values were below the range of the concurrent control values, respectively).
The decreased number of reticulocytes in males treated at 100 mg/kg/day was considered to be unrelated to treatment with the test material as this change was considered the result of slightly high control values which had no dose-related trend.
It should be noted that the apparent decrease in white blood cell and lymphocyte counts in females at 1 000 mg/kg/day was mainly attributed to low individual values of Animal No. 75. As these findings were noted for one animal only it was considered to be of no toxicological significance.
Coagulation parameters of treated rats were considered not to have been affected by treatment with the test material.
The higher prothrombin time (PT) of females treated at 100, 300 and 1 000 mg/kg/day were considered to have arisen as a result of slightly low control values
and therefore considered to be of no toxicological significance with mean PT for treatment groups remaining within the historical control range.

Historical control data for Wistar Han rats; F0-males (period 2017 - 2020): Reticulocytes (10E9/L) mean = 221.5; P5 – P95 = 164.25-288.35 (n=400).
Historical control data for Wistar Han rats; F0-females (period 2017 - 2020): Prothrombin time (sec): mean = 17.6; P5 – P95 = 15.9-19.5 (n=382).

Clinical biochemistry findings:

effects observed, non-treatment-related

Description (incidence and severity):

Clinical biochemistry parameters of treated rats were considered not to have been affected by treatment with the test material up to 1 000 mg/kg/day.
A lower mean albumin concentration noted in females at 1 000 mg/kg/day (0.94x of control) was considered to have arisen as a result of slightly high control values and therefore considered to be of no toxicological significance.
The decreased mean potassium concentration in males at 100 and 300 mg/kg/day was considered to be unrelated to treatment as these occurred in the absence of a dose-related trend.

Historical control data for Wistar Han rats; F0-females (period 2017 - 2020): Albumin: mean = 30.5; P5 – P95 = 27.50-37.20 (n=401).

Endocrine findings:

no effects observed

Description (incidence and severity):

Thyroid hormone analyses: Serum levels of T4 in F0-males were considered unaffected by treatment with the test material up to 1 000 mg/kg/day.

Urinalysis findings:

not examined

Behaviour (functional findings):

no effects observed

Description (incidence and severity):

Functional observation parameters were considered unaffected by treatment with the test material up to 1 000 mg/kg/day.
Hearing ability, pupillary reflex, static righting reflex and grip strength were normal in all examined animals up to 1 000 mg/kg/day.
Motor activity was similar between treated and control groups. All groups showed a similar motor activity habituation profile with a decreasing trend in activity over the duration of the test period.

Immunological findings:

not examined

Organ weight findings including organ / body weight ratios:

effects observed, non-treatment-related

Description (incidence and severity):

There were no test material-related alterations in organ weights.
There was a statistically significant lower brain weight in females at 300 and 1 000 mg/kg/day (absolute only, -5 % for both treatment groups). There was no macroscopic or microscopic correlate for this slightly lower brain weight in the females examined and was therefore regarded of no toxicological significance.

Gross pathological findings:

no effects observed

Description (incidence and severity):

There were no test material-related gross observations.
All of the recorded macroscopic findings were within the range of background gross observations encountered in rats of this age and strain.

Neuropathological findings:

not examined

Histopathological findings: non-neoplastic:

effects observed, non-treatment-related

Description (incidence and severity):

There were no test material-related microscopic observations.
All of the recorded microscopic findings were within the range of background pathology encountered in rats of this age and strain.

Histopathological findings: neoplastic:

no effects observed

Description (incidence and severity):

There were no test material-related microscopic observations.
All of the recorded microscopic findings were within the range of background pathology encountered in rats of this age and strain.

Other effects:

no effects observed

Description (incidence and severity):

- Food consumption: Food consumption before or after correction for body weight was similar to the control level up to 1 000 mg/kg/day.

Effect levels

Key result

Dose descriptor:

NOAEL

Effect level:

> 1 000 mg/kg bw/day (actual dose received)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: No test material-related effects at any dose.

Target system / organ toxicity

Critical effects observed:

no

Any other information on results incl. tables

Dose Range Finder (DRF) Results

Parameter	500 mg/kg/day Group	1 000 mg/kg/day Group
Mortality	No mortality	No mortality
Clinical Appearance	No findings	Hunched posture at 1 and 3 h after dosing in Animal 6 on Day 2; and directly and 1 h after dosing in all animals on Day 4.
Body Weight	Normal body weight gain for Animals 2 and 3 between Days 1 – 5 and 5 – 10. Slight body weight loss (up to 3 %) for Animal 1 between Days 1 – 10.	Normal body weight gain for Animals 4 and 5, and no body weight gain for Animal 6 between Days 1 – 5. Normal body weight gain for all animals between Days 5 – 10.
Food Consumption	Normal	Normal
Macroscopic Examination	No findings noted	No findings noted
Organ Weights	Normal liver and kidney weights.	Lover and kidney weights (absolute and relative to body weight) slightly lower than normal.

Based on the results of the dose range finder, selected dose levels for the Main study were 100, 300 and 1 000 mg/kg/day. Since no clear peak effect of occurrence of clinical signs was observed in the dose range finder, clinical observations were conducted and functional observations were started in the Main study after dosing at no specific time point, but within a similar time period after dosing for the respective animals.

 

 

Main Study Results

Body Weights Summary (Grams)

Males		Group 1 Control	Group 2 100 mg/kg/day	Group 3 300 mg/kg/day	Group 4 1 000 mg/kg/day
Pre-mating
Day 1 Week 1	Mean	287	296	289	29
	St. Dev.	7.8	8.2	7.9	12.9
	N	10	10	10	10
Day 8 Week 2	Mean	300	310	300	307
	St. Dev.	14.5	11.6	13.4	13.9
	N	10	10	10	10
Mating period
Day 1 Week 1	Mean	312	321	313	323
	St. Dev.	17.1	13.2	15.4	14.3
	N	10	10	10	10
Day 8 Week 2	Mean	322	334	326	334
	St. Dev.	17.6	14.0	16.6	15.3
	N	10	10	10	10
Day 15 Week 3	Mean	333	348	340	349
	St. Dev.	19.9	13.3	17.7	18.5
	N	10	10	10	10

 

Body Weights Summary (Grams)

Females		Group 1 Control	Group 2 100 mg/kg/day	Group 3 300 mg/kg/day	Group 4 1 000 mg/kg/day
Pre-mating
Day 1 Week 1	Mean	16	216	219	219
	St. Dev.	9.0	5.0	10.1	10.6
	N	10	10	10	10
Day 8 Week 2	Mean	221	223	222	226
	St. Dev.	9.9	6.5	10.	12.5
	N	10	10	10	10
Mating period
Day 1 Week 1	Mean	224	224	226	229
	St. Dev.	10.0	8.1	11.5	14.4
	N	10	10	10	10
Day 8 Week 2	Mean			-
	St. Dev.			-
	N			0 x
Day 15 Week 3	Mean			-
	St. Dev.			-
	N			0 x

X Excluded data

 

Body Weight Summary: F0 Generation (Grams)

Females		Group 1 Control	Group 2 100 mg/kg/day	Group 3 300 mg/kg/day	Group 4 1 000 mg/kg/day
Post coitum
Day 0	Mean	228	226	225	229
	St. Dev.	10.5	6.4	8.0	12.1
	N	9	10	6	10
Day 4	Mean	239	237	237	242
	St. Dev.	10.4	6.6	9.0	14.8
	N	9	10	6	10
Day 7	Mean	249	243	243	250
	St. Dev.	12.6	6.8	8.8	15.7
	N	9	10	6	10
Day11	Mean	259	256	256	262
	St. Dev.	11.4	7.1	71	17.9
	N	9	10	6	10
Day 14	Mean	268	267	268	270
	St. Dev.	12.1	8.5	9.3	17.8
	N	9	10	6	10
Day 17	Mean	291	288	292	289
	St. Dev.	14.0	11.4	8.3	23.7
	N	9	10	6	10
Day 20	Mean	328	325	329	316
	St. Dev.	17.3	18.5	12.1	35.2
	N	9	10	7	10
Lactation
Day 1	Mean	357	356	253	261
	St. Dev.	16.0	11.7	7.5	20.8
	N	9	10	7	8
Day 4	Mean	261	263	266	271
	St. Dev.	12.9	11.1	13.2	21.5
	N	9	10	7	8
Day 7	Mean	269	269	269	275
	St. Dev.	11.5	8.6	16.8	18.9
	N	9	10	7	8
Day 13	Mean	282	283	287	289
	St. Dev.	13.0	16.7	18.9	15.9
	N	9	10	7	8

 

Body Wight Gain (%) Summary

Males		Group 1 Control	Group 2 100 mg/kg/day	Group 3 300 mg/kg/day	Group 4 1 000 mg/kg/day
Pre-mating
Day 1 Week 1	Mean	0	0	0	0
	St. Dev.	0.0	0.0	0.0	0.0
	N	10	10	10	10
Day 8 Week 2	Mean	4	5	4	6
	St. Dev.	2.8	2.0	2.9	1.8
	N	10	10	10	10
Mating period
Day 1 Week 1	Mean	9	8	8	12
	St. Dev.	4.0	3.2	4.2	3.0
	N	10	10	10	10
Day 8 Week 2	Mean	12	13	13	15
	St. Dev.	4.6	3.5	4.4	3.7
	N	10	10	10	10
Day 15 Week 3	Mean	16	17	18	20
	St. Dev.	5.1	3.4	4.7	4.5
	N	10	10	10	10

 

Females		Group 1 Control	Group 2 100 mg/kg/day	Group 3 300 mg/kg/day	Group 4 1 000 mg/kg/day
Pre-mating
Day 1 Week 1	Mean	0	0	0	0
	St. Dev.	0.0	0.0	0.0	0.0
	N	10	10	10	10
Day 8 Week 2	Mean	2	3	2	3
	St. Dev.	3.2	2.9	2.3	3.4
	N	10	10	10	10
Mating period
Day 1 Week 1	Mean	4	4	3	4
	St. Dev.	4.5	4.0	3.5	3.3
	N	10	10	10	10
Day 8 Week 2	Mean			-
	St. Dev.			-
	N			0 x
Day 15 Week 3	Mean			-
	St. Dev.			-
	N			0x

x Explanations for excluded data are listed in the tables of the individual values

 

Body Weight Gain (%) Summary: F0 Generation

Females		Group 1 Control	Group 2 100 mg/kg/day	Group 3 300 mg/kg/day	Group 4 1 000 mg/kg/day
Post coitum
Day 0	Mean	0	0	0	0
	St. Dev.	0.0	0.0	0.0	0.0
	N	9	10	6	10
Day 4	Mean	5	5	5	6
	St. Dev.	1.2	1.4	0.9	2.7
	N	9	10	6	10
Day 7	Mean	8	7	8	9
	St. Dev.	1.8	1.4	1.8	2.7
	N	9	10	6	10
Day11	Mean	14	13	13	15
	St. Dev.	1.9	1.3	2.0	3.5
	N	9	10	6	10
Day 14	Mean	18	18	19	18
	St. Dev.	0.9	1.8	16	3.1
	N	9	10	6	10
Day 17	Mean	28	27	29	26
	St. Dev.	2.7	3.0	1.9	5.2
	N	9	10	6	10
Day 20	Mean	44	44	47	38
	St. Dev.	5.3	6.4	3.4	10.2
	N	9	10	6	10
Lactation
Day 1	Mean	0	0	0	0
	St. Dev.	0.0	0.0	0.0	0.0
	N	9	10	7	8
Day 4	Mean	2	3	5	4
	St. Dev.	2.8	3.1	3.3	2.0
	N	9	10	7	8
Day 7	Mean	5	5	6	5
	St. Dev.	4.5	2.8	4.9	2.1
	N	9	10	7	8
Day 13	Mean	10	11	13	11
	St. Dev.	5.2	6.1	5.1	6.5
	N	9	10	7	8

 

Food Consumption Summary (g/animal/day)

Males		Group 1 Control	Group 2 100 mg/kg/day	Group 3 300 mg/kg/day	Group 4 1 000 mg/kg/day
Pre-Mating
Days 1 – 8 Weeks 1 - 2	Mean	18	20	18	19
	St. Dev.	0.8	0.3	1.5	0.4
	N (cage)	2	2	2	2
Days 8 – 15 Weeks 2 - 3	Mean	17	18	18	19
	St. Dev.	0.2	0.3	0.2	0.3
	N (cage)	2	2	2	2
Mean of means over pre-mating period	Mean	18	19	18	19
Mating Period
Days 1 – 8 Weeks 1 - 2	Mean	16	18	17	17
	St. Dev.	0.2	0.8	0.7	0.9
	N (cage)	2	2	2	2
Days 8 – 15 Weeks 2 - 3	Mean	17	18	18	18
	St. Dev.	0.4	1.1	0.4	0.1
	N (cage)	2	2	2	2
Mean of means over mating period	Mean	17	18	17	18

 

Females		Group 1 Control	Group 2 100 mg/kg/day	Group 3 300 mg/kg/day	Group 4 1 000 mg/kg/day
Pre-Mating
Days 1 – 8 Weeks 1 - 2	Mean	15	15	15	16
	St. Dev.	1.1	1.2	1.0	0.7
	N (cage)	2	2	2	2
Days 8 – 15 Weeks 2 - 3	Mean	14	14	14	15
	St. Dev.	0.4	1.0	1.8	1.6
	N (cage)	2	2	2	2
Mean of means over pre-mating period	Mean	14	14	14	15
Mating Period
Days 1 – 8 Weeks 1 - 2	Mean		-
	St. Dev.		-
	N (cage)		0

 

Food Consumption Summary (g/animal/day): F0 Generation

Females		Group 1 Control	Group 2 100 mg/kg/day	Group 3 300 mg/kg/day	Group 4 1 000 mg/kg/day
Post Coitum
Days 0 – 4	Mean	13	13	13	13
	St. Dev.	1.6	1.5	1.7	2.3
	N	9	10	6	10
Days 4 – 7	Mean	15	14	14	14
	St. Dev.	1.9	1.3	2.2	2.8
	N	9	10	6	10
Days 7 – 11	Mean	17	16	16	17
	St. Dev.	1.7	1.6	2.2	2.1
	N	9	10	6	10
Days 11 – 14	Mean	19	18	18	18
	St. Dev.	1.6	1.3	1.1	2.2
	N	9	10	6	10
Days 14 – 17	Mean	21	20	21	20
	St. Dev.	1.8	1.8	2.6	2.5
	N	9	10	6	10
Days 17 – 20	Mean	22	22	22	21
	St. Dev.	2.1	1.7	2.1	2.5
	N	9	10	6	10
Mean of means	Mean	18	17	17	17
Lactation
Days 1 – 4	Mean	25	32	31	28
	St. Dev.	6.7	16.5	5.3	5.4
	N	8	9	6	8
Days 4 – 7	Mean	33	34	36	35
	St. Dev.	7.6	7.1	5.3	5.0
	N	9	10	7	8
Days 7 – 13	Mean	44	47	49	48
	St. Dev.	11.9	13.9	6.0	4.8
	N	9	10	7	8
Mean of means	Mean	34	37	39	37

 

Relative Food Consumption Summary (g/kg bw/day)

Males		Group 1 Control	Group 2 100 mg/kg/day	Group 3 300 mg/kg/day	Group 4 1 000 mg/kg/day
Pre-mating
Days 1 – 8 Weeks 1 - 2	Mean	61	63	61	63
	St. Dev.	2.1	0.7	4.1	1.3
	N (cage)	2	2	2	2
Days 8 – 15 Weeks 2 - 3	Mean	58	58	60	60
	St. Dev.	0.2	1.4	1.6	0.8
	N (cage)	2	2	2	2
Mean of means over pre-mating period	Mean	60	61	60	62
Mating Period
Days 1 – 8 Weeks 1 - 2	Mean	51	53	51	52
	St. Dev.	0.0	2.2	2.2	2.9
	N (cage)	2	2	2	2
Days 8 – 15 Weeks 2 - 3	Mean	50	52	52	51
	St. Dev.	0.5	2.8	0.8	0.9
	N (cage)	2	2	2	2
Mean of means over mating period	Mean	51	52	52	51

 

Females		Group 1 Control	Group 2 100 mg/kg/day	Group 3 300 mg/kg/day	Group 4 1 000 mg/kg/day
Pre-mating
Days 1 – 8 Weeks 1 - 2	Mean	66	66	67	71
	St. Dev.	5.1	3.9	3.4	1.0
	N (cage)	2	2	2	2
Days 8 – 15 Weeks 2 - 3	Mean	65	63	63	65
	St. Dev.	1.9	3.0	7.1	4.9
	N (cage)	2	2	2	2
Mean of means over pre-mating period	Mean	66	64	65	68
Mating Period
Days 1 – 8 Weeks 1 - 2	Mean		-
	St. Dev.		-
	N (cage)		0

 

Relative Food Consumption Summary (g/kg bw/day): F0 Generation

Females		Group 1 Control	Group 2 100 mg/kg/day	Group 3 300 mg/kg/day	Group 4 1 000 mg/kg/day
Post Coitum
Days 0 – 4	Mean	56	53	54	55
	St. Dev.	5.9	5.6	5.7	7.9
	N	9	10	6	10
Days 4 – 7	Mean	62	58	57	57
	St. Dev.	5.7	4.8	8.7	9.2
	N	9	10	6	10
Days 7 – 11	Mean	66	63	62	64
	St. Dev.	6.0	5.7	7.3	5.9
	N	9	10	6	10
Days 11 – 14	Mean	69	67	68	68
	St. Dev.	3.7	4.8	3.7	5.0
	N	9	10	6	10
Days 14 – 17	Mean	72	69	71	69
	St. Dev.	4.9	5.7	7.5	4.1
	N	9	10	6	10
Days 17 – 20	Mean	67	68	66	67
	St. Dev.	3.3	4.5	4.3	3.3
	N	9	10	6	10
Mean of means	Mean	65	63	63	63
Lactation
Days 1 – 4	Mean	97	120	113	103
	St. Dev.	26.3	55.2	17.2	15.7
	N	8	9	6	8
Days 4 – 7	Mean	121	125	133	129
	St. Dev.	28.1	24.5	13.1	13.0
	N	9	10	7	8
Days 7 – 13	Mean	158	163	171	167
	St. Dev.	41.8	42.4	12.3	13.5
	N	9	10	7	8
Mean of means	Mean	125	136	139	133

 

Functional Observations

Males		Group 1 Control	Group 2 100 mg/kg/day	Group 3 300 mg/kg/day	Group 4 1 000 mg/kg/day
Hearing Score 0/1	Mean	0	0	0	0
	N	5	5	5	5
Pupil L Score 0/1	Mean	0	0	0	0
	N	5	5	5	5
Pupil R Score 0/1	Mean	0	0	0	0
	N	5	5	5	5
Static R score 0/1	Mean	0	0	0	0
	N	5	5	5	5
Grip Force Gram	Mean	1223	1258	1223	1131
	St. Dev.	69	95	124	47
	N	5	5	5	5
Grip Hind Gram	Mean	817	761	742	732
	St. Dev.	50	78	62	91
	N	5	5	5	5

 

Females		Group 1 Control	Group 2 100 mg/kg/day	Group 3 300 mg/kg/day	Group 4 1 000 mg/kg/day
Hearing Score 0/1	Mean	0	0	0	0
	N	5	5	5	5
Pupil L Score 0/1	Mean	0	0	0	0
	N	5	5	5	5
Pupil R Score 0/1	Mean	0	0	0	0
	N	5	5	5	5
Static R score 0/1	Mean	0	0	0	0
	N	5	5	5	5
Grip Force Gram	Mean	962	918	936	960
	St. Dev.	111	139	89	137
	N	5	5	5	5
Grip Hind Gram	Mean	383	321	387	340
	St. Dev.	48	72	60	63
	N	5	5	5	5

 

Motor Activity Test Summary: Males

Total Movements	Group 1 Control	Group 2 100 mg/kg/day	Group 3 300 mg/kg/day	Group 4 1 000 mg/kg/day
Mean	3144	3023	3067	3416
N	5	5	5	5
St. Dev.	919	664	416	767

 

Motor Activity Test Summary: Males

Ambulations	Group 1 Control	Group 2 100 mg/kg/day	Group 3 300 mg/kg/day	Group 4 1 000 mg/kg/day
Mean	693	759	633	714
N	5	5	5	5
St. Dev.	245	237	207	172

 

Motor Activity Test Summary: Females

Total Movements	Group 1 Control	Group 2 100 mg/kg/day	Group 3 300 mg/kg/day	Group 4 1 000 mg/kg/day
Mean	3600	4208	4020	3797
N	5	5	5	5
St. Dev.	857	885	1458	1107

 

Motor Activity Test Summary: Females

Ambulations	Group 1 Control	Group 2 100 mg/kg/day	Group 3 300 mg/kg/day	Group 4 1 000 mg/kg/day
Mean	889	1098	1001	904
N	5	5	5	5
St. Dev.	260	370	519	306

 

Summary of Haematology Values: F0 Generation

Day 30 Relative to Start Date

Male		WBC (10^9/L) [G]	NEUT (10^9/L) [G]	LYMPH (10^9/L) [G]	MONO (10^9/L) [GI]	EOS (10^9/L) [G]	BASO (10^9/L) [G]	LUC (10^9/L) [G]	RBC (10^9/L) [G]	RETIC (10^9/L) [G]	RDWG (%) [G]	HGB (g/L) [G]	HCT (L/L) [G]
0 mg/kg/day Group 1	Mean	7.242	1.206	5.798	0.108	0.068	0.014	0.052	8.930	300.32	12.22	158.0	0.4524
	SD	1.850	0.711	1.404	0.036	0.016	0.009	0.022	0.810	36.96	0.60	6.3	0.0160
	N	5	5	5	5	5	5	5	5	5	5	5	5
100 mg/kg/day Group 2	Mean	6.460	0.954	5.312	0.090	0.058	0.016	0.030	8.444	238.2*	12.38	155.2	0.4322
	SD	1.890	0.120	1.958	0.029	0.011	0.011	0.016	0.447	19.26	0.54	9.1	0.0245
	N	5	5	5	5	5	5	5	5	5	5	5	5
	tCtrl	0.89	0.79	0.92	0.83	0.85	1.14	0.58	0.95	0.79	1.01	0.98	0.96
300 mg/kg/day Group 3	Mean	7.804	1.198	6.366	0.104	0.066	0.014	0.052	8.752	257.76	12.34	156.2	0.4506
	SD	2.036	0.524	1.827	0.013	0.043	0.009	0.025	0.661	25.62	0.59	8.6	0.024
	N	5	5	5	5	5	5	5	5	5	5	5	5
	tCtrl	1.08	0.99	1.10	0.96	0.97	1.00	1.00	0.98	0.86	1.01	0.99	1.00
1 000 mg/kg/day Group 4	Mean	6.804	1.128	5.456	0.102	0.054	0.016	0.050	8.330	252.30	13.40	154.2	0.4378
	SD	1.996	0.535	1.563	0.029	0.017	0.005	0.026	0.467	43.24	0.98	9.4	0.0315
	N	5	5	5	5	5	5	5	5	5	5	5	5
	tCtrl	0.94	0.94	0.94	0.94	0.79	1.14	0.96	0.93	0.84	1.10	0.98	0.97

[G] - Anova & Dunnett: * = p ≤ 0.05

 

Summary of Haematology Values: F0 Generation

Day 30 Relative to Start Date

Male		MCV (fL) [G]	MCH (pg) [GI]	MCHC (g/L) [GI]	PLT (10^9/L) [G]
0 mg/kg/day Group 1	Mean	50.86	17.78	349.4	690.8
	SD	3.11	1.05	2.6	57.4
	N	5	5	5	5
100 mg/kg/day Group 2	Mean	51.18	18.36	358.6	646.6
	SD	0.97	0.22	7.8	111.3
	N	5	5	5	5
	tCtrl	1.01	1.03	1.03	0.94
300 mg/kg/day Group 3	Mean	51.62	17.90	346.8	745.0
	SD	2.36	0.84	2.6	79.4
	N	5	5	5	5
	tCtrl	1.01	1.01	0.99	1.08
1 000 mg/kg/day Group 4	Mean	52.64	18.54	352.4	713.2
	SD	4.29	1.29	5.0	122.5
	N	5	5	5	5
	tCtrl	1.03	1.04	1.01	1.03

[G] - Anova & Dunnett

[G1] - Kruskal-Wallis & Dunn

 

Summary of Haematology Values: F0 Generation

Day 51 Relative to Start Date

Female		WBC (10^9/L) [G]	NEUT (10^9/L) [G]	LYMPH (10^9/L) [G]	MONO (10^9/L) [GI]	EOS (10^9/L) [G]	BASO (10^9/L) [G]	LUC (10^9/L) [G]	RBC (10^9/L) [G]	RETIC (10^9/L) [G]	RDWG (%) [G]	HGB (g/L) [G]	HCT (L/L) [G]
0 mg/kg/day Group 1	Mean	5.810	1.664	3.946	0.098	0.076	0.005	0.022	7.284	272.96	12.90	141.8	0.4220
	SD	0.939	0.210	0.812	0.031	0.030	0.004	0.008	0.353	50.30	0.39	5.7	0.0193
	N	5	5	5	5	5	5	5	5	5	5	5	5
100 mg/kg/day Group 2	Mean	5.024	1.274	3.582	0.084	0.066	0.006	0.016	7.116	035.00	12.98	135.4	0.4016
	SD	0.733	0.327	0.635	0.017	0.057	0.005	0.005	0.400	47.31	1.18	3.0	0.0068
	N	5	5	5	5	5	5	5	5	5	5	5	5
	tCtrl	0.86	0.77	0.91	0.86	0.87	0.75	0.73	0.98	0.86	1.01	0.95	0.95
300 mg/kg/day Group 3	Mean	5.204	1.624	3.366	0.106	0.090	0.006	0.014	6.94	258.84	13.70	133.4*	0.4004
	SD	1.229	0.517	0.752	0.057	0.053	0.005	0.005	0.623	29.06	1.72	6.0	0.0186
	N	5	5	5	5	5	5	5	5	5	5	5	5
	tCtrl	0.90	0.98	0.85	1.08	1.18	0.75	0.64	0.95	0.95	1.06	0.94	0.95
1 000 mg/kg/day Group 4	Mean	4.604	1.310	3.124	0.086	0.064	0.004	0.018	6.890	276.78	12.84	132.4*	0.3958
	SD	0.434	0.128	0.481	0.017	0.046	0.005	0.011	0.216	29.58	0.73	5.1	0.00137
	N	5	5	5	5	5	5	5	5	5	5	5	5
	tCtrl	0.79	0.79	0.79	0.88	0.84	0.50	0.82	0.95	1.01	1.00	0.93	0.94

[G] - Anova & Dunnett

* = p ≤ 0.05

[G1] - Kruskal-Wallis & Dunn

 

Summary of Haematology Values: F0 Generation

Day 51 Relative to Start Date

Female		MCV (fL) [G]	MCH (pg) [GI]	MCHC (g/L) [GI]	PLT (10^9/L) [G]
0 mg/kg/day Group 1	Mean	57.94	19.48	336.6	687.6
	SD	1.30	0.61	6.9	134.7
	N	5	5	5	5
100 mg/kg/day Group 2	Mean	56.58	19.04	337.0	759.4
	SD	2.72	0.76	6.0	128.7
	N	5	5	5	5
	tCtrl	0.98	0.98	1.00	1.10
300 mg/kg/day Group 3	Mean	58.28	19.42	333.4	520.2
	SD	4.28	1.28	8.6	98.7
	N	5	5	5	5
	tCtrl	1.01	1.00	0.99	1.19
1 000 mg/kg/day Group 4	Mean	57.44	19.20	334.4	735.8
	SD	1.72	0.46	6.8	67.3
	N	5	5	5	5
	tCtrl	0.99	0.99	0.99	1.07

 

Summary of Coagulation Values: F0 Generation

Day 30 Relative to Start Date

Male		PT (sec) [G]	APTT (sec) [G]
0 mg/kg/day Group 1	Mean	16.48	14.00
	SD	1.23	3.82
	N	5	5
100 mg/kg/day Group 2	Mean	17.36	15.10
	SD	1.25	5.21
	N	5	5
	tCtrl	1.05	1.08
300 mg/kg/day Group 3	Mean	16.68	13.60
	SD	0.71	2.33
	N	4	4
	tCtrl	1.01	0.97
1 000 mg/kg/day Group 4	Mean	17.10	16.44
	SD	1.56	3.46
	N	5	5
	tCtrl	1.04	1.17

[G] - Anova & Dunnett

 

Summary of Coagulation Values: F0 Generation

Day 51 Relative to Start Date

Female		PT (sec) [G]	APTT (sec) [G]
0 mg/kg/day Group 1	Mean	15.70	15.84
	SD	0.44	1.69
	N	5	5
100 mg/kg/day Group 2	Mean	16.46*	16.16
	SD	0.54	1.62
	N	5	5
	tCtrl	1.05	1.02
300 mg/kg/day Group 3	Mean	16.42*	16.44
	SD	0.43	1.92
	N	5	5
	tCtrl	1.05	1.04
1 000 mg/kg/day Group 4	Mean	16.76**	16.14
	SD	0.27	2.86
	N	5	5
	tCtrl	1.07	1.02

[G] - Anova & Dunnett: * = p ≤ 0.05; ** = p ≤ 0.01

 

Summary of Clinical Chemistry Values: F0 Generation

Day 30 Relative to Start Date

Male		ALT (U/L) [G]	AST (U/L) [G]	ALP (U/L) [GI]	TPROT (g/L) [GI]	ALB (g/L) [GI]	BILEAC (umol/L) [G]	TBIL (umol/L) [GI]	UREA (mmol/L) [GI]	CREAT (umol/L) [G]	GLUC (mmol/L) [GI]	CHOL (mmol/L) [GI]	NA (mmol/L) [GI]
0 mg/kg/day Group 1	Mean	81.0	83.7	156.3	62.20	38.62	52.13	2.38	6.15	29.3	10.742	1.686	144.2
	SD	12.9	10.8	36.4	2.93	1.60	14.62	0.16	1.31	1.5	1.029	0.065	0.4
	N	5	5	5	5	5	5	5	5	5	5	5	5
100 mg/kg/day Group 2	Mean	74.3	87.9	138.3	59.38	36.74	39.83	2.30	6.18	30.9	9.492	1.426	144.0
	SD	12.5	15.0	24.0	1.17	0.90	25.04	0.28	0.56	2.3	1.127	0.210	1.2
	N	5	5	5	5	5	5	5	5	5	5	5	5
	tCtrl	0.92	1.05	0.88	0.95	0.95	0.76	0.97	1.00	1.06	0.88	0.85	1.00
300 mg/kg/day Group 3	Mean	149.5	181.4	173.8	62.48	38.92	67.52	2.56	6.61	28.3	9.132	1.666	144.2
	SD	141.1	220.7	38.3	2.58	1.64	9.09	0.26	0.78	5.3	1.350	0.151	0.8
	N	5	5	5	5	5	5	5	5	5	5	5	5
	tCtrl	1.85	2.17	1.11	1.00	1.01	1.30	1.08	1.07	0.97	0.52	0.99	1.00
1 000 mg/kg/day Group 4	Mean	92.6	84.3	154.2	63.34	38.52	40.36	2.50	5.87	30.9	9.640	1.728	143.8
	SD	24.0	12.2	18.9	2.36	1.83	9.10	0.19	0.75	2.4	2.134	0.372	1.8
	N	5	5	5	5	5	5	5	5	5	5	5	5
	tCtrl	1.14	1.01	0.99	1.02	1.00	0.77	1.05	0.95	1.06	0.90	1.02	1.00

[G] - Kruskal-Wallis & Dunn [G1] - Anova & Dunnett

 

Summary of Clinical Chemistry Values: F0 Generation

Day 30 Relative to Start Date

Male		K (mmol/L) [GI]	CL (mmol/L) [GI]	CA (mmol/L) [GI]	PHOS (mmol/L) [GI]	T4 (mmol/L) [GI]
0 mg/kg/day Group 1	Mean	4.49	105.6	2.652	1.988	40.77
	SD	0.21	1.3	0.073	0.258	7.96
	N	5	5	5	5	10
100 mg/kg/day Group 2	Mean	3.94**	105.6	2.532	1.846	4.02
	SD	0.12	1.1	0.073	0.206	11.12
	N	5	5	5	5	10
	tCtrl	0.88	1.00	0.95	0.93	1.08
300 mg/kg/day Group 3	Mean	3.93**	104.8	2.724	1.920	44.96
	SD	0.21	1.1	0.159	0.197	8.14
	N	5	5	5	5	10
	tCtrl	0.87	0.99	1.03	0.97	1.10
1 000 mg/kg/day Group 4	Mean	4.23	1.06	2.690	2.096	44.30
	SD	0.22	0.7	0.099	0.219	7.87
	N	5	5	5	5	10
	tCtrl	0.94	1.00	1.01	1.05	1.09

[G] - Anova & Dunnett: ** = p ≤ 0.01

 

Summary of Clinical Chemistry Values: F0 Generation

Day 51 Relative to Start Date

Female		ALT (U/L) [G]	AST (U/L) [G]	ALP (U/L) [GI]	TPROT (g/L) [GI]	ALB (g/L) [GI]	BILEAC (umol/L) [G]	TBIL (umol/L) [GI]	UREA (mmol/L) [GI]	CREAT (umol/L) [G]	GLUC (mmol/L) [GI]	CHOL (mmol/L) [GI]	NA (mmol/L) [GI]
0 mg/kg/day Group 1	Mean	118.5	90.0	249.6	56.48	34.64	24.87	2.28	9.06	23.1	8.304	1.950	140.6
	SD	12.2	8.3	121.9	2.27	1.29	20.07	0.47	0.77	2.8	1.167	0.329	2.7
	N	5	5	5	5	5	5	5	5	5	5	5	5
100 mg/kg/day Group 2	Mean	128.0	93.3	157.9	53.88	33.06	25.45	2.13	8.82	24.7	8.316	1.878	140.8
	SD	42.3	10.0	35.0	2.08	1.27	18.83	0.32	1.15	2.4	2.126	0.259	1.6
	N	5	5	5	5	5	5	5	5	5	5	5	5
	tCtrl	1.08	1.04	0.75	0.95	0.95	1.02	0.95	0.96	1.07	1.00	0.96	1.00
300 mg/kg/day Group 3	Mean	119.2	93.5	211.0	54.82	33.76	21.42	2.12	9.68	22.0	7.530	1.734	141.4
	SD	8.5	6.4	103.7	0.88	0.52	9.48	0.49	0.91	2.6	1.341	0.311	0.9
	N	5	5	5	5	5	5	5	5	5	5	5	5
	tCtrl	1.01	1.04	0.85	0.97	0.97	0.86	0.93	1.07	0.95	0.91	0.89	1.01
1 000 mg/kg/day Group 4	Mean	122.5	94.8	184.0	53.30	32.62*	18.87	2.12	9.42	24.3	7.844	1.930	139.8
	SD	29.6	11.0	76.4	1.98	1.01	15.66	0.38	0.73	3.3	1.205	0.430	0.4
	N	5	5	5	5	5	5	5	5	5	5	5	5
	tCtrl	1.03	1.05	0.74	0.94	0.94	0.76	0.93	1.04	1.05	0.94	0.99	0.99

[G] - Anova & Dunnett: * = p ≤ 0.05 [G1] - Kruskal-Wallis & Dunn

 

Summary of Clinical Chemistry Values: F0 Generation

Day 51 Relative to Start Date

Female		K (mmol/L) [GI]	CL (mmol/L) [GI]	CA (mmol/L) [GI]	PHOS (mmol/L) [GI]
0 mg/kg/day Group 1	Mean	4.58	106.6	2.148	0.772
	SD	0.48	3.0	0.043	0.287
	N	5	5	5	5
100 mg/kg/day Group 2	Mean	4.48	104.8	2.472	1.514
	SD	0.75	3.7	0.082	0.529
	N	5	5	5	5
	tCtrl	0.98	0.98	1.02	1.96
300 mg/kg/day Group 3	Mean	4.66	105.8	2.506	1.408
	SD	0.44	1.5	0.080	0.873
	N	5	5	5	5
	tCtrl	1.02	0.99	1.04	1.82
1 000 mg/kg/day Group 4	Mean	4.70	105.6	2.518	1.588
	SD	0.14	1.9	0.055	0.624
	N	5	5	5	5
	tCtrl	1.03	0.99	1.04	2.06

[G] - Anova & Dunnett

 

Macropscopic Findings Summary

End of Treatment

Males	Group 1 Control	Group 2 100 mg/kg/day	Group 3 300 mg/kg/day	Group 4 1 000 mg/kg/day
Animals examined	10	10	10	10
Animals without findings	9	10	7	9
Animals affected	1	0	3	1
Liver:
- Focus/foci	0	0	1	0
- Hardened	0	0	1	0
- Discolouration	0	0	1	0
Pancreas- gelatinous	0	0	1	0
Testes - agenesis	0	0	1	0
Epididymides – Agenesis	0	0	1	0
Pituitary gland – Cyst(s)	1	0	0	0
Mesenteric lymph node discolouration	0	0	1	0
Skin – Scab formation	0	0	0	1

 

 

Females	Group 1 Control	Group 2 100 mg/kg/day	Group 3 300 mg/kg/day	Group 4 1 000 mg/kg/day
Animals examined	10	10	10	10
Animals without findings	8	6	8	7
Animals affected	2	4	2	3
Uterus
-Thickened	0	0	1	0
-Contents	0	0	0	1
Clitoral glands – focus/foci	1	0	0	0
Placenta – contains fluid	0	0	0	1
Thyroid gland
-Reduced in size	0	1	0	0
-Discolouration	0	0	1	0
Thymus - foci	0	2	0	0
Mesenteric lymph node
-Enlarged	0	0	1	0
-Discolouration	0	0	0	1
Mandibular lymph node - discolouration	1	0	1	0
Skin
-Alopecia	1	0	0	0
-Wound(s)	0	0	0	1
-Scab formation	0	1	0	0
Body cavities – contains fluid	0	0	0	1

# / ## Fisher's Exact test significant at 5 % (#) or 1 % (##) level

 

Organ Weights Summary (grams)

Males		Group 1 Control	Group 2 100 mg/kg/day	Group 3 300 mg/kg/day	Group 4 1 000 mg/kg/day
Bodyweight (g)	Mean	317	330	323	331
	St. Dev.	20	12	16	16
	N	10	10	10	10
Brain	Mean	1.97	1.96	1.96	1.97
	St. Dev.	0.05	0.07	0.04	0.04
	N	5	5	5	5
Heart	Mean	0.935	0.927	0.927	0.970
	St. Dev.	0.070	0.021	0.062	0.104
	N	5	5	5	5
Liver	Mean	8.06	7.74	8.09	8.44
	St. Dev.	1.09	0.46	0.48	1.10
	N	5	5	5	5
Thyroids	Mean	0.0142	0.0168	0.0142	0.0167
	St. Dev.	0.0022	0.0027	0.0029	0.0033
	N	10	10	10	10
Thymus	Mean	0.285	0.310	0.330	0.326
	St. Dev.	0.054	0.027	0.113	0.083
	N	5	5	5	5
Kidneys	Mean	2.07	2.09	2.08	2.25
	St. Dev.	0.19	0.20	0.12	0.34
	N	5	5	5	5
Adrenals	Mean	0.056	0.065	0.058	0.061
	St. Dev.	0.012	0.014	0.005	0.014
	N	5	5	5	5
Spleen	Mean	0.617	0.563	0.557	0.608
	St. Dev.	0.122	0.096	0.076	0.147
	N	5	5	5	5
Testes	Mean	3.35	3.32	3.12	3.29
	St. Dev.	0.36	0.28	0.25	0.36
	N	10	10	9	10
Prostate gland	Mean	0.763	0.847	0.817	0.749
	St. Dev.	0.107	0.103	0.130	0.159
	N	10	10	10	10
Epididymides	Mean	1.042	1.045	1.034	1.083
	St. Dev.	0.098	0.078	0.073	0.097
	N	10	10	9	10
Seminal vesicles	Mean	1.318	1.259	1.187	1.281
	St. Dev.	0.146	0.113	0.181	0.108
	N	10	10	10	10

*/** Dunnett-test based on pooled variance significant at 5% (*) or 1% (**) level

 

Organ/Body Weight Ratios (%) Summary

Males		Group 1 Control	Group 2 100 mg/kg/day	Group 3 300 mg/kg/day	Group 4 1 000 mg/kg/day
Bodyweight (g)	Mean	317	330	323	331
	St. Dev.	20	12	16	16
	N	10	10	10	10
Brain	Mean	0.62	0.60	0.61	0.60
	St. Dev.	0.03	0.01	0.05	0.04
	N	5	5	5	5
Heart	Mean	0.293	0.282	0.290	0.294
	St. Dev.	0.018	0.010	0.029	0.018
	N	5	5	5	5
Liver	Mean	2.53	2.36	2.52	2.55
	St. Dev.	0.36	0.15	0.07	0.22
	N	5	5	5	5
Thyroids	Mean	0.0045	0.0051	0.0044	0.0050
	St. Dev.	0.0006	0.0009	0.0009	0.0009
	N	10	10	10	10
Thymus	Mean	0.089	0.094	0.102	0.098
	St. Dev.	0.017	0.008	0.032	0.021
	N	5	5	5	5
Kidneys	Mean	0.65	0.64	0.65	0.68
	St. Dev.	0.05	0.05	0.02	0.07
	N	5	5	5	5
Adrenals	Mean	0.018	0.020	0.018	0.018
	St. Dev.	0.004	0.004	0.001	0.004
	N	5	5	5	5
Spleen	Mean	0.193	0.171	0.174	0.183
	St. Dev.	0.040	0.030	0.023	0.037
	N	5	5	5	5
Testes	Mean	1.06	1.01	0.96	0.99
	St. Dev.	0.12	0.07	0.09	0.09
	N	10	10	9	10
Prostate gland	Mean	0.241	0.257	0.255	0.226
	St. Dev.	0.033	0.035	0.049	0.045
	N	10	10	10	10
Epididymides	Mean	0.329	0.317	0.319	0.327
	St. Dev.	0.035	0.021	0.026	0.023
	N	10	10	9	10
Seminal vesicles	Mean	0.416	0.383	0.368	0.387
	St. Dev.	0.048	0.042	0.054	0.033
	N	10	10	10	10

*/** Dunnett-test based on pooled variance significant at 5% (*) or 1% (**) level

 

Organ Weights Summary: End of Treatment (grams)

Females		Group 1 Control	Group 2 100 mg/kg/day	Group 3 300 mg/kg/day	Group 4 1 000 mg/kg/day
Bodyweight (g)	Mean	272	284	271	281
	St. Dev.	20	16	30	20
	N	10	10	10	10
Brain	Mean	197	1.94	1.87*	1.87*
	St. Dev.	0.04	0.05	0.05	0.08
	N	5	5	5	5
Heart	Mean	0.810	0.831	0.782	0.885
	St. Dev.	0.072	0.063	0.052	0.050
	N	5	5	5	5
Liver	Mean	12.00	11.64	11.44	12.85
	St. Dev.	1.28	2.03	1.19	0.79
	N	5	5	5	5
Thyroids	Mean	0.0153	0.0162	0.0171	0.0165
	St. Dev.	0.0035	0.0034	0.0024	0.0033
	N	10	10	10	10
Thymus	Mean	0.190	0.183	0.215	0.210
	St. Dev.	0.045	0.056	0.027	0.041
	N	5	5	5	5
Kidneys	Mean	1.96	1.87	1.79	2.02
	St. Dev.	0.22	0.19	0.08	0.10
	N	5	5	5	5
Adrenals	Mean	0.072	0.071	0.069	0.072
	St. Dev.	0.006	0.008	0.009	0.012
	N	5	5	5	5
Spleen	Mean	0.504	0.491	0.179	0.521
	St. Dev.	0.053	0.068	0.014	0.027
	N	5	5	5	5
Ovaries	Mean	0.118	0.117	0.109	0.104
	St. Dev.	0.014	0.012	0.014	0.015
	N	5	5	5	5
Uterus	Mean	0.366	0.373	0.340	0.366
	St. Dev.	0.040	0.065	0.054	0.020
	N	5	5	5	5

*/** Dunnett-test based on pooled variance significant at 5% (*) or 1% (**) level

 

Organ/Body Weight Ratios (%) Summary: End of Treatment

Females		Group 1 Control	Group 2 100 mg/kg/day	Group 3 300 mg/kg/day	Group 4 1 000 mg/kg/day
Bodyweight (g)	Mean	272	284	271	281
	St. Dev.	20	16	30	20
	N	10	10	10	10
Brain	Mean	0.7	0.68	0.37	0.64
	St. Dev.	0.05	0.06	0.07	0.03
	N	5	5	5	5
Heart	Mean	0.290	0.289	0.279	0.303
	St. Dev.	0.026	0.008	0.006	0.018
	N	5	5	5	5
Liver	Mean	4.31	4.03	4.08	4.40
	St. Dev.	0.47	0.48	0.17	0.35
	N	5	5	5	5
Thyroids	Mean	0.0056	0.0057	0.0064	0.0059
	St. Dev.	0.0014	0.0012	0.0013	0.0011
	N	10	10	10	10
Thymus	Mean	0.068	0.065	0.077	0.072
	St. Dev.	0.013	0.024	0.010	0.014
	N	5	5	5	5
Kidneys	Mean	0.70	0.65	0.64	0.69
	St. Dev.	0.05	0.03	0.04	0.05
	N	5	5	5	5
Adrenals	Mean	0.026	0.025	0.025	0.025
	St. Dev.	0.003	0.001	0.001	0.004
	N	5	5	5	5
Spleen	Mean	0.81	0.171	0.172	0.179
	St. Dev.	0.022	0.021	0.013	0.013
	N	5	5	5	5
Ovaries	Mean	0.042	0.041	0.039	0.036
	St. Dev.	0.003	0.005	0.006	0.006
	N	5	5	5	5
Uterus	Mean	0.131	0.131	0.123	0.125
	St. Dev.	0.015	0.027	0.027	0.007
	N	5	5	5	5

*/** Dunnett-test based on pooled variance significant at 5% (*) or 1% (**) level

Applicant's summary and conclusion

Conclusions:

Under the conditions of the study, the NOAEL for the test material was > 1 000 mg/kg/day.

Executive summary:

The repeated dose toxicity of the test material was assessed according to OECD test Guideline 422 and in compliance with GLP.

The objectives of this study were to determine the potential toxic effects of the test material when given orally by gavage for a minimum of 28 days to Wistar Han rats.

No Observed Adverse Effect Levels (NOAELs) were evaluated. The dose levels in this study were selected to be 0, 100, 300, 1 000 mg/kg/day, based on the results of the Dose Range Finder (Test Facility Study No. 20236631). The study design was as follows. Test groups consisting of 10 males and 10 females were administered with 100, 300 or 1 000 mg/kg/day of test material. A control group receive the vehicle only.

The following parameters and end points were evaluated in this study: Mortality/ moribundity, clinical signs, functional observations, body weight and food consumption, oestrous cycle, clinical pathology, measurement of thyroid hormone T4 (F0-males), gross necropsy findings, organ weights and histopathologic examinations.

Analysis of test material in vehicle for concentration, homogeneity, and stability was not performed in this study. No feasible analytical method was available, since the test material did not dissolve in any vehicle/solution at all. Due to these test material characteristics and procedures of test formulation preparation/administration in this study (formulations were prepared daily protected from light, considered to be homogeneous after visual inspection and stirred continuously during dose administration within 2 hours after preparation), this GLP exception was considered as being minor with no impact on the outcomes and the integrity and the achievement of the objective of the study.

No toxicologically relevant parental toxicity was noted up to 1 000 mg/kg/day. The decreased haemoglobin concentration in females at 300 and 1 000 mg/kg/day was considered not to be toxicologically relevant, since these changes were not associated with any corroborating findings or any pathological alterations. No mortality and no toxicologically significant changes were noted in any of the other parameters investigated in this study (i.e. clinical appearance, functional observations (motor activity, grip strength, hearing ability, pupillary reflex and static righting reflex), body weight, food consumption, clinical laboratory investigations, clotting parameters and clinical biochemistry (including male T4 thyroid hormone levels), macroscopic examination, organ weights, and microscopic examination).

Under the conditions of the study, the NOAEL for the test material was > 1 000 mg/kg/day.