Vanadate(1-), oxo[phosphato(3-)-.kappa.O]-, hydrogen, hydrate (2:2:1)

Repeated dose toxicity: oral

Administrative data

Endpoint:

short-term repeated dose toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Meets generally accepted scientific standards, well documented and acceptable for assessment.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1991

Report date:

1991

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Divanadyl pyrophosphate

EC Number:

407-130-0

EC Name:

Divanadyl pyrophosphate

Cas Number:

65232-89-5

Molecular formula:

(VO)2P2O7

IUPAC Name:

Divanadyl pyrophosphate

Details on test material:

- Name of test material (as cited in study report): E-326 Catalyst
- Physical state: grey/green powder
- Analytical purity: 96%
- Lot/batch No.: 104
- Storage condition of test material: at 13 °C protected from light.

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River (UK)
- Age at study initiation: 32-40 days
- Weight at study initiation: 73-86 g
- Housing: 5 animals per cage
- Diet: LAD1 complete, pelleted laboratory rodent diet (Biosure, UK), ad libitum
- Water: tap water, ad libitum
- Acclimation period: 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 18 - 25 °C
- Humidity (%): 40 - 70 %
- Air changes (per hr): 15
- Photoperiod (hrs dark / hrs light): 12 h / 12 h

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

other: 1% methylcellulose in distilled water

Details on oral exposure:

PREPARATION OF DOSING SOLUTIONS:
Formulations of the test material were prepared for administration as a series of graded concentrations in 1% w/v methylcellulose in distilled water to provide the required dosages at a constant volume-dosage. Control rats received the vehicle alone at the same volume-dosage. All formulation were prepared freshly each day.


VEHICLE
- Amount of vehicle (if gavage): 10 ml/kg bodyweight

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Homogeneity was determined by atomic absorption spectrophotometric analysis of total Vanadium content of the trial formulations for the high and low dosage groups immediately following their preparation. Stability was assessed by analysis of the infra-red spectra of evaporated samples after 24 and 48 hours storage at room temperature. In addition, duplicate samples (2 ml each) of each formulation prepared for administration on the first day of treatmentand on one occasion in Week 4 of treatment were retrospectively analysed by atomic absorption spectrophotometry for achieved concentration.

Duration of treatment / exposure:

30 days

Frequency of treatment:

daily

Doses / concentrations

Remarks:

Doses / Concentrations:
0, 20, 100, 500 mg/kg bw
Basis:
actual ingested

No. of animals per sex per dose:

5

Control animals:

yes, concurrent vehicle

Details on study design:

- Dose selection rationale:
Four groups of three male and three female rats were given E-326 catalyst in 1% w/v methyl cellulose in distilled water once daily by oral gavage for seven days at dosages of 30, 100, 250 or 500 mg/kg/day, at a volume-dosage of 10 ml/kg bodyweight. Serial examinations were confined to observation of clinical signs and bodyweight recordings. No test substance related signs of toxicity were reported. Thus, dosages of 20, 100 and 500 mg/kg/day were selected for the main study. Based on toxicity data provided by the Sponsor, the high dosage of 500 mg/kg/day was considered to be the maximum that could be administered without significant risk of death from acute effects of treatment.

Examinations

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: twice daily

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: weekly

BODY WEIGHT: Yes
- Time schedule for examinations: twice weekly

HAEMATOLOGY: Yes
- Time schedule for collection of blood: day 29
- Anaesthetic used for blood collection: Yes
- Animals fasted: Yes, overnight
- How many animals: all
- Parameters examined: packed cell volume, haemoglobin concentration, erythrocyte count, total and differential leucocyte count, platelet count, mean cell haemoglobin, mean cell volume.

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: day 29
- Animals fasted: Yes, overnight
- How many animals: all
- Parameters examined: alkaline phosphatase, alanine amino-transferase, aspartate amino-transferase, urea, creatinine, glucose, bilirubin, total protein, sodium, potassium, chloride, calcium, inorganic phosphorus.

URINALYSIS: Yes
- Time schedule for collection of urine: day 25
- Metabolism cages used for collection of urine: Yes
- Animals fasted: Yes
- Parameters examined: appearance, volume, pH, specific gravity, protein, glucose, ketones, bilirubin, urobilinogen, nitrite, blood

Sacrifice and pathology:

GROSS PATHOLOGY: Yes, detailed examination of the external features and orifices, the neck and the subcutaneous structures and the cranial, thoracic, pelvic and abdominal cavities and their viscera. Organ weight from adrenals, heart, kidneys, liver, spleen, testes was recorded.

HISTOPATHOLOGY: Yes, abnormalities, adrenals, heart, kidneys, liver, spleen.

Statistics:

The following test were used: student`s t-test, Dunnett´s or Fisher-Behrens tests and Fisher Exact Probability test.

Results and discussion

Results of examinations

Details on results:

CLINICAL SIGNS AND MORTALITY
500 mg/kg bw: One male rat showed bodyweight loss and was found dead on day 20. One female showed bodyweight loss from the beginning of the study, loose faeces, hunched posture and piloerection on Day 3 and was killed on Day 4 for humanity reasons. A further female was hunched, thin and had reduced body temperature and muscle tone, muscle tremor, rapid respiration, piloerection and pallor on Day 21, and was killed for humanity reasons on the same day. Three females showed salivation.
100 mg/kg bw: Salivation of a single female

BODY WEIGHT AND WEIGHT GAIN
500 mg/kg bw: slighly lower body weight gain (females)

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study)
500 mg/kg bw: Slighly lower food consumption, particularly during the first week of treatment (females)

HAEMATOLOGY
500 mg/kg/day: lowered mean red cell-volumes, haemoglobin concentrations and packed cell volumes slightly reduced and red cell numbers slightly elevated. slightly reduced lymphocyte and corresponding total leucocyte numbers and slightly higher platelet counts (females)

CLINICAL CHEMISTRY
500 mg/kg bw: Elevated plasma amino-transferase activities, elevated plasma ure concentrations (males), reduced plasma alkaline phosphatase activity (females)
100 mg/kg bw: elevated plasma amino-transferase activities (females)

URINALYSIS
No test substance- related effects

ORGAN WEIGHTS
No test substance- related effects

GROSS PATHOLOGY
No test substance- related effects

HISTOPATHOLOGY:
Histopathology of the male that died revealed diminished glycogen and congestion in the liver. Histopathology of one female that was sacrificed revealed papillary mineralisation in the right kidney, plasmocytosis and parafollicular hyperplasia in the mesenteric lymph nodes and diminished glycogen and congestion in the liver. The second female that was sacrificed, showed hydronephrosis and vacuolation or degeneration of the right kidney tubules, hepatocytic degeneration and inflammation, diminished glycogen and congestion in the liver and atrophy of the splenic white pulp. In the surviving animals there were no other microscopic changes which were attributed to treatment.

Effect levels

1

Dose descriptor:

NOAEL

Effect level:

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

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: clinical signs; mortality;

2

Dose descriptor:

NOEL

Effect level:

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

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: clinical chemistry;

Target system / organ toxicity

Critical effects observed:

not specified

Any other information on results incl. tables

In conclusion, the oral administration at a dosage of 500 mg/kg/day for four consecutive weeks caused the death of three rats, haematological alterations and changes in blood chemistry. The no observed adverse effect level (NOAEL) under the conditions of the present study was 100 mg/kg bw/day for both sexes.