Hexafluorosilicic acid

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

yes

Remarks:

fish size ranged from 33 to 75 mm, no control results reported

Principles of method if other than guideline:

Screening study of acute fish toxicity: limited details

GLP compliance:

no

Remarks:

: published report

Analytical monitoring:

not specified

Vehicle:

yes

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: direct solution
- Controls:blank dilution medium
- Evidence of undissolved material (e.g. precipitate, surface film, etc.): not reported

Test organisms (species):

Lepomis macrochirus

Details on test organisms:

Lepomis macrochirus (freshwater)
TEST ORGANISM
- Common name: Bluegill sunfish; Lepomis macrochirus
- Source: Commercial hatchery in the vincinity of New York
- Length at study initiation (length definition, mean, range and SD): 33 - 75 mm

ACCLIMATION
- Acclimation period: 14 days
- Acclimation conditions (same as test or not): same
- Health during acclimation (any mortality observed): if > 5% mortality, the batch was judged "unfit"

FEEDING DURING TEST
no feeding during test

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Post exposure observation period:

Non

Hardness:

55 mg/L as CaCO3

Test temperature:

23°C

pH:

7.6-7.9 (dilution water)

Nominal and measured concentrations:

Nominal :control, 32, 56, 75, 100 mg/L

Details on test conditions:

Limited details.TEST SYSTEM
- Test vessel: 5 gallon
- Type (delete if not applicable): open
- Aeration: when needed
- No. of organisms per vessel: not reported
- No. of vessels per concentration (replicates): not reported
- No. of vessels per control (replicates): not reported
- Biomass loading rate: less than 1 g/L

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: well water
- Intervals of water quality measurement: weekly

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: not reported
- Light intensity: not reported

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
mortality(daily up to 96 hours)

TEST CONCENTRATIONS
- Spacing factor for test concentrations: ca.1.8

Reference substance (positive control):

not specified

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

65 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

- Mortality of control: on average 1.3%
- Effect concentrations exceeding solubility of substance in test medium: no

Sublethal observations / clinical signs:

Disodium hexafluorosilicic acid shows a 96 h-LC50 on Lepomis macrochirus of 65 mg/l.

Validity criteria fulfilled:

not applicable

Executive summary:

The authors investigated the acute fish toxicity 47 substances in a series of screening studies. Disodium hexafluorosilicic acid showed a 96 h-LC50 on Lepomis macrochirus of 65 mg/l.

Reference 2

Endpoint:

short-term toxicity to fish

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Justification for type of information:

see read across justification

Reason / purpose for cross-reference:

read-across source

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

160 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

disodium hexafluorosilicic acid

Basis for effect:

mortality (fish)

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

123 mg/L

Nominal / measured:

nominal

Conc. based on:

other: hexafluorosilicic acid

Basis for effect:

mortality (fish)

Remarks on result:

other: Result calculated for hexafluorosilicic acid using the conversion factor as outlined in the read across justification.

Details on results:

Applying the conversion factor from disodiumhexafluorosilicic acid to hexafluorosilicic acid, the concentration corresponds to 123 mg hexafluorosilicic acid/L.

Validity criteria fulfilled:

not applicable

Executive summary:

The authors investigated the acute fish toxicity 47 substances in a series of screening studies. Disodium hexafluorosilicic acid shows a 96 h-LC50 on the marine species Menidia beryllina of 160 mg/L.

Applying the conversion factor from disodiumhexafluorosilicic acid to hexafluorosilicic acid, the concentration corresponds to 123 mg hexafluorosilicic acid/L.

Description of key information

Hexafluorosilicic acid shows a 96 h-LC50 on Lepomis macrochirus of 50 mg/L (freshwater).

Hexafluorosilicic acid shows a 96 h-LC50 on Menidia beryllina of 123 mg/L (marine).

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

50 mg/L

Marine water fish

Marine water fish

Effect concentration:

123 mg/L

Additional information

For the assessment of the acute toxicity to fish, several studies with read across substances are available. The read across justification is provided in a separate document. The LC50 values results of the read across substances were converted to the concentration of hexafluorosilicic acid.

For freshwater fish following acute toxicity data (LC50 values) are available:

Lepomis macrochirus: 50 mg/L (key)

Oncorhynchus mykiss: 64-252 mg/L

Oncorhynchus mykiss: 135.5 mg/L

Salmo trutta: 207.3 mg/L

EU-RAR: 64.3 - 207.9 mg/L

ICD: 64.3 – 428.4 mg/L

 

For marine fish following acute toxicity data (LC50 values) are available:

Menidia beryllina: 123 mg/L (key)

EU-RAR: 161.3 to 579.6 mg/L (reported to be higher than the water solubility of NaF in seawater and may hence be an overestimation of the toxicity to marine fish)

 

The data demonstrate that freshwater fish are more sensitive than marine fish and that the LC50 values of 50 and 123 mg/L for freshwater and marine fish, respectively, are conservative.