Potassium tetrafluoroborate

Repeated dose toxicity: oral

Administrative data

Endpoint:

short-term repeated dose toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP-compliant guideline study, available as unpublished report, no restrictions, fully adequate for assessment.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1997

Report date:

1997

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 407 (Repeated Dose 28-Day Oral Toxicity Study in Rodents)

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.7 (Repeated Dose (28 Days) Toxicity (Oral))

GLP compliance:

yes (incl. QA statement)

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Potassium tetrafluoroborate

EC Number:

237-928-2

EC Name:

Potassium tetrafluoroborate

Cas Number:

14075-53-7

Molecular formula:

BF4.K

IUPAC Name:

potassium tetrafluoroborate

Test material form:

solid: particulate/powder

Details on test material:

- Name of test material (as cited in study report): Kaliumtetrafluoroborat
- Physical state: white crystalline powder
- Analytical purity: 100.1%
- Purity test date: July 08, 1996
- Lot/batch No.: 6107A
- Expiration date of the lot/batch: July 1998
- Stability under test conditions: is guaranteerd for 4 hours according to report of Analytical Toxicology dated September 20, 1996
- Storage condition of test material: darkness at room temperature in a fume cupboard

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Hochst Aktiengesellschaft, Kastengrund, SPF breeding colony
- Age at study initiation: ca. 8 weeks
- Weight at study initiation: mean 116.2 (SD = 3.52) for males and 113.6 (SD = 2.32) for females
- Housing: in fully air-conditioned rooms in makrolon cages (type 4) on soft wood granulate in groups of 5 animals
- Diet: Ssniff R/M-H (V 1534), ad libitum, except for the period in which the animals were kept in diuresis cages
- Water: tap water in plastic bottles ad libitum, except for the period when the animals were kept in diuresis cages
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 3
- Humidity (%): 50 ± 20
- Photoperiod (hrs dark / hrs light): 12 / 12

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

water

Details on oral exposure:

PREPARATION OF DOSING SOLUTIONS: The test compound was dissolved homogeneously in the vehicle by means of a magnetic stirrer. Fresh solutions were prepared daily.

VEHICLE
- Concentration in vehicle: 0, 0.4, 1.6 and 6.4% (w/v)
- Amount of vehicle (if gavage): 5 mL/kg bw

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Determination of the test substance was performed by RI-detection after HPLC-separation on a reverse phase column.

Duration of treatment / exposure:

28 applications within 29 days

Frequency of treatment:

daily

Doses / concentrations

Remarks:

Doses / Concentrations:
0, 20, 80 and 320 mg/kg bw/day
Basis:
actual ingested

No. of animals per sex per dose:

15/sex/dose in the controls and high-dose groups; 10/sex/dose in low- and mid-dose groups

Control animals:

yes, concurrent vehicle

Details on study design:

- Dose selection rationale: based on the results of the 5-day dose-range finding study
- Rationale for selecting satellite groups: 5 males and 5 females were placed in the recovery groups for the controls and high-dose group
- Post-exposure recovery period in satellite groups: 14 days
- Section schedule rationale (if not random): on day 29, 5 males and 5 females from each group were killed and necropsied. The remaining animals of the control and high dose group were killed and necropsied after a recovery period of 14 days

Examinations

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: once daily for the behavior and general health condition; once weekly for neurological disturbances, opacity of the refracting media of the eyes, damage to the oral mucosa and impairment of dental growth.

BODY WEIGHT: Yes
- Time schedule for examinations: before the start of the study and then twice weekly.

FOOD CONSUMPTION: Food consumption was determined continuously (2 times/week). The values were converted to the food consumption per 100 g body weight over a 24 hour period.

WATER CONSUMPTION: Yes
- Time schedule for examinations: once weekly over a period of 16 hours and reported as water consumption/animal/16 h.

OPHTHALMOSCOPIC EXAMINATION: opacity of the refracting media of the eyes was examined once weekly.

HAEMATOLOGY: Yes
- Time schedule for collection of blood: at the termination of the study and after the recovery period.
- Anaesthetic used for blood collection: Yes (intraperitoneal injection of 50-100 mg Ketamin Hydrochlorid and Xylazin (67 / 6.7 mg/kg bw))
- Animals fasted: no
- How many animals: all animals
- Parameters examined were: erythrocyte count, haemoglobin, hematocrit, mean corpuscular volume (MCV), meacn corpuscular haemoglobin (MCH), mean corpuscular haemoglobin concentration (MCHC), leucocyte count, thrombocyte count, differential leucocyte count and red cell morphology, reticulocyte count, Heinz bodies and coagulation time.

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: after blood sampling for hematological testing
- Animals fasted: no
- How many animals: all animals
- Parameters examined: sodium, potassium, inorganic phosphorus, uric acid, bilirubin total, bilirubin direct,creatinine, glucose, urea, calcium, chloride, aspartate aminotransferase (ASAT/GOT), alanine aminotransferase (ALAT/GLP), alkaline phosphatase (AP), gamma-glutamyltraspeptidase (GGT), cholesterol, triglycerides, total protein, albumin.

URINALYSIS: Yes
- Time schedule for collection of urine: a few days before termination of the study
- Metabolism cages used for collection of urine: yes
- Animals fasted: yes
- Parameters examined: appearance, colour, pH-value, haemoglobin, protein, glucose, ketone bodies, bilirubin, urobilinogen, specific weight, sediment, volume

NEUROBEHAVIOURAL EXAMINATION: Animals were examined once weekly for neurological disturbances

BIOCHEMICAL INVESTIGATIONS: after 8 days, at termination of the study and after the recovery period, biochemical examinations were performed in all animals without previous withdrawal of food. Blood samples were taken from the retroorbital venous plexus in narcosis (intraperitoneal injection of 50-100 mg Ketamin Hydrochlorid + Xylazin (67 / 6.7 mg/kg bw)). The following parameters were examined: total thyroxine, triiodothyronine, thyroid-stimulating hormone.

Sacrifice and pathology:

GROSS PATHOLOGY: Yes. The autopsy included macroscopic examination of the skin, orifices, eyes, teeth, oral mucosal and internal organs. The following organs were weighed: heart, liver, kidneys, adrenal glands, spleen, ovaries, testes, lung, pituitary gland, thyroid glands, brain.
HISTOPATHOLOGY: Yes. The following organs were examined in all dose groups: thyroid glands, parathyroid glands. The following organs were examined in the control and high dose groups: heart, liver, lung, kidneys, adrenal glands, spleen, eyes, ovaries, testes, epididymides, pituitary gland, thyroid glands, parathyroid glands, stomach, jejunum, colon, duodenum, ileum, caecum, rectum, uterus, bone marrow (sternum), femur, with knee joint, brain with medulla oblongate, urinary bladder, lymph nodes (mandibulare), lymph nodes, aorta, mammary gland, N. ischiaticus, oesophagus, pancreas, prostate gland, spinal cord (cervical), sceletal muscle, salivary glands, traches, thymus, brain.

Statistics:

The following parameters were compared statistically with the control group values at the level of significance p = 0.05: body weight at the designated measurement times; hematological data; clinical chemistry parameters; urinalysis (volume, pH value and specific weight), absolute organ weights and organ to body weight ratios. Evaluation was performed by Pharma Informatics with the aid of program package for the evaluation of toxicological studies.

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):

no effects observed

Ophthalmological findings:

no effects observed

Haematological findings:

effects observed, treatment-related

Clinical biochemistry findings:

effects observed, treatment-related

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

Details on results:

CLINICAL SIGNS AND MORTALITY
No deaths occurred throughout the study. Behavior and state of healh remained unaffected by the administration of the test compound in all dose groups.

BODY WEIGHT AND WEIGHT GAIN
Body weight development was not impaired by the administration of te test compound and was comparable in all groups.

FOOD CONSUMPTION
Absolute and relative food consumption remained unaffected by the administration of the test compound.

WATER CONSUMPTION
The administration of the test compound did not alter water consumption.

OPHTHALMOSCOPIC EXAMINATION
Compound related changes in the opacity of the refracting media of the eyes were not observed.

HAEMATOLOGY
Statistically significant decreases in erythrocyte counts and hematocrit value were observed in female animals of the intermediate and high dose group. Females of the high dose group also showed decreased hemoglobin values. The reduced leukocyte counts in females of the intermediate dose group were not considered compound-related since they were within the physiological range and there was no dose-dependency.
In the recovery group, the thrombocyte counts were increased to a statistically significant degree in females of the high dose group. This effect is not considered to be relevant since the values were within the physiological range of rats.

CLINICAL CHEMISTRY
Males from the intermediate dose group showed increases in inorganic phosphate values. In females statistical evaluation revealed increases in sodium values in the low dose group as well as decreased ALAT, serum glucose, and inorganic phosphate values in the intermediate dose group, and decreased protein value in the high dose group. Males and females from the high dose group exhibited statistically significant increases in urea value. In all cases there was no dose dependency or the values were within the physiological range of rats. Therefore, a compound-related effect was not evident.
In the recovery group, the creatinine value was decreased to a statistically significant degree in the males of the high dose group. This is not considered to be compound-related since the values were within the physiological range of rats and the values of the control group were relatively high.

URINALYSIS
No treatment-related changes were observed.

NEUROBEHAVIOUR
No compound-related neurological disturbances were observed.

ORGAN WEIGHTS
Absolute and relative organ weights of the final and the recovery values were not altered by the administration of the test compound except for an increase in relative kidney weights in males of the high dose recovery group. This finding was not considered to be compound-related since the values were within the physiological range of rats and the values of the control group were relatively low.

GROSS PATHOLOGY
No compound-related macroscopic findings were observed. In male and female animals from all dose groups including control, unilateral dilatation of the kidney pelvis occurred. Type and distribution of these findings indicate that they were spontaneous in origin.

HISTOPATHOLOGY: NON-NEOPLASTIC
Histopathological examination did not reveal any compound-related lesions. In rats with dilatation of the kidney pelvis no underlying lesion could be detected which is consistent with previous experience showing that this finding is a congenital condition of unknown etiology inherent to Wistar rats of the strain used.

OTHER FINDINGS: no treatment-related changes were detected by the examination of the thyroid hormone levels in all dose groups, including recovery groups.

Effect levels

1

Dose descriptor:

NOEL

Effect level:

20 mg/kg bw/day (actual dose received)

Based on:

test mat.

Sex:

female

Basis for effect level:

other: Based on a slight reduction in erythrocyte counts, hemoglobin and hematocrit values in intermediate and high dose females, fully reversible after 14 days recovery period.

2

Dose descriptor:

NOAEL

Effect level:

320 mg/kg bw/day (actual dose received)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: No adverse effects were observed at the highest dose level.

Target system / organ toxicity

Critical effects observed:

not specified

Applicant's summary and conclusion

Conclusions:

A NOAEL of 320 mg/kg bw/day, the highest dose tested, was established in a 28-day oral gavage study in rats.

Executive summary:

In a GLP-compliant OECD Guideline 407 study, groups of 10 male and female Wistar rats were administered the test substance in aqueous solution by gavage at dose levels of 0, 20, 80 or 320 mg/kg bw/day for 28 days, 7 days per week. In addition 5 male and 5 female animals from the control and high dose group were placed in the recovery groups for a recovery period of 14 days. Animals were observed for clinical signs, body weight, food and water consumption. Hematological and clinical chemistry examinations were performed at the termination of the study and after the recovery period on all animals. Urinalysis was performed on all animals a few days before termination of the study. After 8 days, at the termination fo the study and after the recovery period, biochemical examination was performed on all animals, including examination of total thyroxine, triiodothyronine and thyroid-stimulation hormone levels. All animals were subjected to necropsy, including macroscopic examination of the skin, orifices, eyes, teeth, oral mucosa and internal organs. Animals of the control and high dose groups were subjected to histopathological examinations. No mortalities or clinical signs were observed in the study. There were no effects on food and water consumption, body weight and body weight gain. No macroscopically visible changes were seen, which were considered to be compound-related. Organ weights were unaffected by treatment. Histopathological examination did not reveal any compound-related effect. Hematological examinations revealed slight but statistically significant decreases in erythrocytes counts and hematocrit value in female animals of the intermediate and high dose group. Females of the high dose group also showed slightly decreased hemoglobin values. The MCV values were not affected. All findings on hematological parameters were completely reversible after a 14-day recovery period. No treatment-related changes were detected by examination of the thyroid hormone levels in all dose groups. Clinical chemistry examinations revealed no compound-related changes in any dose group. No treatment-related changes were detected by urinalysis. Based on the slight decrease in erythrocytes counts and hematocrit and hemoglobin values in intermediate and high-dose females, which were fully reversible after 14 days recovery period, the lowest dose level of 20 mg/kg bw/day is considered to be a NOEL for females. Based on the lack of adverse changes the highest dose level of 320 mg/kg bw/day is considered to be a NOAEL for males and females.