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Administrative data

Description of key information

The LD50 of ammonium hexafluorosilicate was considered to be 70 mg/kg bw.

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Referenceopen allclose all

Endpoint:
acute toxicity: oral
Type of information:
experimental study
Adequacy of study:
key study
Study period:
1988
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Data from a publication
Justification for type of information:
Refer chapter 13 for detailed read across justification
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 401 (Acute Oral Toxicity)
Deviations:
not specified
GLP compliance:
not specified
Test type:
standard acute method
Specific details on test material used for the study:
None
Species:
mouse
Strain:
not specified
Sex:
not specified
Details on test animals and environmental conditions:
None
Route of administration:
oral: drinking water
Vehicle:
water
Details on oral exposure:
None
Doses:
None
No. of animals per sex per dose:
Not specified
Control animals:
not specified
Details on study design:
None
Statistics:
None
Key result
Sex:
not specified
Dose descriptor:
LD50
Effect level:
70 mg/kg bw
Based on:
test mat.
Mortality:
Details not available
Clinical signs:
- PERIPHERAL NERVE AND SENSATION: Flaccid paralysis without anesthesia (usually neuromuscular blockage);
- BEHAVIORAL: Ataxia;
- BEHAVIORAL: Muscle contraction or spasticity
Body weight:
Details not available
Gross pathology:
Details not available
Other findings:
None

None

Interpretation of results:
Category 3 based on GHS criteria
Conclusions:
LD50 for sodium hexafluorosilicate was found to be 70 mg/kg bw.
Executive summary:

The acute oral toxicity of sodium hexafluorosilicate was evaluated in this study conducted with mice. The test substance was administered via drinking water. Flaccid paralysis resulting from neuromuscular blockage, ataxia and muscle contraction or spasticity were the clinical signs observed in this study. The study concluded that the LD50 for sodium hexafluorosilicate was 70 mg/kg bw.

Endpoint:
acute toxicity: oral
Type of information:
read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
key study
Study period:
1988
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Data from a publication
Justification for type of information:
Refer chapter 13 for detailed read across justification
Reason / purpose:
read-across source
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 401 (Acute Oral Toxicity)
Deviations:
not specified
GLP compliance:
not specified
Test type:
standard acute method
Specific details on test material used for the study:
None
Species:
mouse
Strain:
not specified
Sex:
not specified
Details on test animals and environmental conditions:
None
Route of administration:
oral: drinking water
Vehicle:
water
Details on oral exposure:
None
Doses:
None
No. of animals per sex per dose:
Not specified
Control animals:
not specified
Details on study design:
None
Statistics:
None
Key result
Sex:
not specified
Dose descriptor:
LD50
Effect level:
70 mg/kg bw
Based on:
test mat.
Mortality:
Details not available
Clinical signs:
- PERIPHERAL NERVE AND SENSATION: Flaccid paralysis without anesthesia (usually neuromuscular blockage);
- BEHAVIORAL: Ataxia;
- BEHAVIORAL: Muscle contraction or spasticity
Body weight:
Details not available
Gross pathology:
Details not available
Other findings:
None

None

Interpretation of results:
Category 3 based on GHS criteria
Conclusions:
LD50 for sodium hexafluorosilicate was found to be 70 mg/kg bw.
Executive summary:

The acute oral toxicity of sodium hexafluorosilicate was evaluated in this study conducted with mice. The test substance was administered via drinking water. Flaccid paralysis resulting from neuromuscular blockage, ataxia and muscle contraction or spasticity were the clinical signs observed in this study. The study concluded that the LD50 for sodium hexafluorosilicate was 70 mg/kg bw.

Endpoint conclusion
Endpoint conclusion:
adverse effect observed
Dose descriptor:
LD50
70 mg/kg bw

Acute toxicity: via inhalation route

Endpoint conclusion
Endpoint conclusion:
no study available

Acute toxicity: via dermal route

Endpoint conclusion
Endpoint conclusion:
no study available

Additional information

The hexafluorosilicates disassociate into hexafluorosilicate ion and corresponding cation when dissolved in water. Further the hexafluorosilicate ion dissociates to fluoride ions and hydrated silica and the disassociation is essentially complete at the pH of drinking water (6.5–8.5) (NTP, 2001; NICNAS, 2017). The monovalent cations and hydrated silica are known to have low toxicity. Hence, the fluoride ion is considered to be the driver of toxicity. Taking this into consideration, in addition to limited details available about acute toxicity of ammonium hexafluorosilicate or sodium hexafluorosilicate, data available for sodium fluoride (CAS No. 7681-49-4) has been used for in this summary, to support the conclusion.

The acute oral toxicity of sodium hexafluorosilicate was evaluated in a study conducted with mice (Rumyantsev et al,1988). The test substance was administered via drinking water. Flaccid paralysis resulting from neuromuscular blockage, ataxia and muscle contraction or spasticity were the clinical signs observed in this study. The study concluded that the LD50 for sodium hexafluorosilicate was 70 mg/kg bw.

Further references discuss the LD50 of sodium hexaflurorosilicate to be 125 mg/kg bw in rats as well as rabbits, though further details about the study conditions are not available (RTECS: sodim hexafluorosilicate, as available on 17 July, 2017).

Ammonium hexafluorosilicate has been described to have the LD50 of 100 mg/kg bw (NICNAS, 2017). However, no further details are available.

Sodium fluoride has been reported to have LD50 of 31–101 mg fluoride/kg bw in rats, while in mice it was 44.3 and 58 mg fluoride/kg bw (Fluorides: Environmental Health Criteria 227, World Health Organization Geneva, 2002).

Hence, the data on sodium fluorides also supports the conclusion that ammonium hexafluorosilicate is highly toxic, and should be classified as acute toxicity category 3 according to the CLP.

Justification for classification or non-classification

Based on the available data, ammonium hexafluorosilicate should be classified as acute toxicity category 3 according to the CLP (Regulation EC No. 1272/2008) criteria.