Dipotassium hexafluorozirconate

Endpoint summary

Description of key information

Acute oral toxicity: a key study is available, indicating a LD50 between 25 and 200 mg/kg, thus justifying classification as Category 3.
Acute inhalation toxicity: Acute inhalation toxicity: Based on particle size considerations, incl. modelling on inhalability and fractional deposition in the respiratory tract, inhalation does not appear to be a relevant route of exposure for K2ZrF6, and testing has been waived.
Acute dermal toxicity: The physicochemical and toxicological properties of K2ZrF6 do not suggest potential for a significant rate of absorption through the skin. Therefore, testing for acute dermal toxicity is not required.

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1995-05-03 to 1995-06-06

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: GLP study reliable with restrictions - only a range-finding study is reported, with a reduced number of animals and three widely spread doses - the purity and the stability of the test material were missing in the study report

Qualifier:

according to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

Version / remarks:

, 1987-02-24

Deviations:

yes

Remarks:

range-finder study only

GLP compliance:

yes (incl. QA statement)

Remarks:

signed 1994-03-16

Test type:

standard acute method

Limit test:

no

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Age at study initiation: approximately five to eight weeks old
- Weight at study initiation: males: 143 - 163 g; females 134 - 155 g
- Fasting period before study: overnight fast immediately before dosing and for approximately two hours after dosing.
- Housing: the animals were housed in groups of two by sex in solid-floor polypropylene cages furnished with woodflakes.
- Diet (ad libitum, except for a fasting period as described above): Rat and Mouse Expanded Diet No. 1, Special Diets Services Limited, Witham, Essex, U.K.
- Water (ad libitum, except for a fasting period as described above): mains drinking water
- Acclimation period: at least five days

ENVIRONMENTAL CONDITIONS
- Temperature: 19 - 23°C
- Relative humidity: 44 - 57%
- Air exchanges: approximately 15 changes per hour
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: From: To:

Route of administration:

oral: gavage

Vehicle:

arachis oil

Details on oral exposure:

MAXIMUM DOSE VOLUME APPLIED: 10 mL/kg; the volume administered to each animal was calculated according to its fasted bodyweight at the time of dosing.

DOSAGE PREPARATION: the test material was freshly prepared as a suspension at the appropriate concentration in arachis oil B.P.

Doses:

25, 200 and 2000 mg/kg
(concentrations: 2.5, 20 and 200 mg/mL)

No. of animals per sex per dose:

2 males / 2 females

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: deaths and overt signs of toxicity were recorded 0.5, 1, 2 and 4 hours after dosing and then daily for fourteen days.
Individual bodyweights were recorded on the day of treatment (day 0) and on days 7 and 14. Bodyweights were not recorded at death for animals dosed at 2000 mg/kg bodyweight.
- Necropsy of survivors performed: yes
At the end of the study the surviving animals were killed by cervical dislocation and all animals including those which died during the study were subjected to gross pathological examination. This consisted of an external examination and opening of the abdominal and thoracic cavities. The appearance of any macroscopic abnormalities was recorded. No tissues were retained.

Statistics:

Using the mortality data obtained, an estimate of the acute oral median lethal dose (LD50) of the test material was made.

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 25 - < 200 mg/kg bw

Based on:

test mat.

Mortality:

All animals died within 1 hour of dosing at the 2000 mg/kg dose level (2/2 males; 2/2 females). At the 200 mg/kg dose level 1/2 males and 1/2 females) died within 4 hours of dosing.

Clinical signs:

other: No signs of systemic toxicity were noted at the 25 mg/kg dose level. Common signs of systemic toxicity noted at the 200 and/or 2000 mg/kg dose levels were ptosis, hunched posture, lethargy, ataxia, decreased respiratory rate, laboured respiration, pilo-er

Gross pathology:

No abnormalites were noted at necropsy of animals which were killed at the end of the study.
Abnormalities noted at necropsy of animals at the 200 mg/kg and/or 2000 mg/kg dose level were abnormally red or haemorrhagic lungs, dark liver, dark kidneys, severe haemorrhaging or epithelial sloughing of the glandular region of the stomach, haemorrhaging/severe haemorrhaging of the small intestine and severe haemorrhaging of the large intestine.

Interpretation of results:

Toxicity Category III

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

The acute oral median lethal dose (LD50) of the test material in the rat was found to be greater than 25 mg/kg bodyweight, but less than 200 mg/kg bodyweight.
According to 67/548/EC and subsequent regulations, dipotassium hexafluorozirconate is classified as toxic if swallowed.
According to the EC Regulation No. 1272/2008 and subsequent regulations, dipotassium hexafluorozirconate is classified as Category 3.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Additional information

Justification for selection of acute toxicity – oral endpoint
Key study.

Justification for classification or non-classification

Acute oral toxicity: a key study is available, indicating a LD50 between 25 and 200 mg/kg, thus justifying classification as Category 3. Acute inhalation toxicity: Acute inhalation toxicity: Based on particle size considerations, incl. modelling on inhalability and fractional deposition in the respiratory tract, inhalation does not appear to be a relevant route of exposure for K2ZrF6, and testing has been waived.

Acute dermal toxicity: The physicochemical and toxicological properties of K2ZrF6 do not suggest potential for a significant rate of absorption through the skin. Therefore, testing for acute dermal toxicity is not required, and neither is classification.