Synthetic amorphous magnesium silicate, with molar ratio (SiO2:MgO) range of 1.4-4

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Reference 1

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:

It is considered appropriate to address the data requirements for synthetic amorphous magnesium silicate by read-across to the available studies on structurally similar substances.
Short-term toxicity studies on fish are available on silicon dioxide and sodium aluminium silicate (NAS). Due to sharing similar structural, physical and chemical properties to synthetic amorphous magnesium silicate, silicon dioxide and NAS are considered appropriate for read-across purposes.

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Specific details on test material used for the study:

Silicon dioxide and sodium aluminium silicate (NAS) are being used as a read-across for synthetic amphorus magnesium silicate.

Duration:

96 h

Dose descriptor:

LL0

Effect conc.:

10 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks:

0/20 animals died

Remarks on result:

other: Data from Hooftman (1992) key study on silicon dioxide

Duration:

96 h

Dose descriptor:

LL0

Effect conc.:

10 000 mg/L

Nominal / measured:

nominal

Basis for effect:

mortality (fish)

Remarks on result:

other: WAF of loading (filtered water extract)

Remarks:

Data from Lebertz (1998) supporting study on sodium aluminium silicate

Details on results:

Key data from short-term fish toxicity studies on silicon dioxide and sodium aluminium silicate (NAS) are used for read-across to synthetic amorphous magnesium silicate.

Conclusions:

The acute toxicity of the target substance, synthetic amorphous magnesium silicate, to fish was estimated to be low (96 h LL0 = 10000 mg/L), based on read-across studies testing silicon dioxide and sodium aluminium silicate.

Executive summary:

Acute fish toxicity studies are available for the read-across substances silicon dioxide and sodium aluminium silicate (NAS). Due to sharing similar structural, physical and chemical properties to synthetic amorphous magnesium silicate, silicon dioxide and NAS is considered appropriate for read-across purposes.  

No animal deaths were reported after the 96 h in both silicon dioxide exposure and NAS exposure studies. The acute toxicity of the target substance, synthetic amorphous magnesium silicate, to fish was therefore estimated to be low (96 h LL0 = 10000 mg/L), based on read-across studies testing silicon dioxide and NAS.

Reference 2

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

19 Nov. 1991 - 23 Nov. 1991

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Reason / purpose for cross-reference:

reference to other study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

GLP compliance:

yes

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: stirring for 20 h, then allowed to stand  for 4 h before testing;
- Eluate: no, suspensions were tested
- Differential loading: yes, 1000 + 10,000 mg/L
- Controls: Synthetic medium from groundwater
- Evidence of undissolved material (e.g. precipitate, surface film, etc): The resulting suspensions at the beginning of the test were homogeneous and milky, at the end of the test in addition a layer of white, starchy flocks on the bottom of the vessels was observed.

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

TEST ORGANISM
- Common name: Zebra fish
- Strain:
- Source: M.B. Ruysbroek B.V./Noordvliet 159, Maassluis
- Age at study initiation (mean and range, SD):
- Length at study initiation (length definition, mean, range and SD): 2.2 +-0.2 cm
- Weight at study initiation (mean and range, SD): 0.09 +-0.02 g
- Method of breeding:
- Feeding during test: no


ACCLIMATION
- Acclimation period: no data
- Type and amount of food: no data
- Feeding frequency: no data

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Post exposure observation period:

none

Hardness:

204 mg/L as CaCO3

Test temperature:

24.5 - 25.3 °C

pH:

7.3 - 8.2

Dissolved oxygen:

7.1 - 8.2 mg/L

Salinity:

not applicable

Nominal and measured concentrations:

1000 and 10,000 mg SiO2/L (nominal)

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Type (delete if not applicable): open
- Material, size, headspace, fill volume: glass beaker, 2 L, 1000 ml test suspension
- Aeration: slight aeration (no data)
- Type of flow-through (e.g. peristaltic or proportional diluter): --
- Renewal rate of test solution (frequency/flow rate): no
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): 2
- No. of vessels per control (replicates): 2
- No. of vessels per vehicle control (replicates): --
- Biomass loading rate: approx. 0.9 g fish/L


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: prepared from groundwater by addition of several salts
- Total organic carbon: 1.7 mg/L
- Alkalinity: -- no data
- Ca/Mg ratio: 1.83
- Conductivity: --



OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16 h light, 8 h dark
- Light intensity: -- no data


EFFECT PARAMETERS MEASURED (with observation intervals if applicable): survival. swimming behaviour, colour, respiratory function,
morphological and physiological changes that were visually observable at 24, 48, 72, and 96 h


TEST CONCENTRATIONS
- Spacing factor for test concentrations: 10
- Justification for using less concentrations than requested by guideline: limit test, expected low toxicity
- Range finding study
- Test concentrations: --
- Results used to determine the conditions for the definitive study: --

Reference substance (positive control):

no

Duration:

96 h

Dose descriptor:

LL0

Effect conc.:

10 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks:

: 0/20 animals died

Details on results:

- Behavioural abnormalities: none
- Observations on body length and weight: none
- Other biological observations: no particular findings
- Mortality of control: none
- Other adverse effects control: none
- Abnormal responses: none

Results with reference substance (positive control):

not applicable

Reported statistics and error estimates:

not applicable

Validity criteria fulfilled:

yes

Conclusions:

Aerosil 200 was not acutely toxic to Brachydanio rerio at a loading of 10,000 mg/l.

Executive summary:

After 96 h of exposure all animals were alive and their condition (swimming behaviour, colour, respiratory function or any other visually observable morphological or behavioural criterion) was equal to that of the control animals.

Reference 3

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

09 Dec. 1991 - 13 Dec. 1991

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Reason / purpose for cross-reference:

reference to other study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

GLP compliance:

yes

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: stirring for 20 h, then allowed to stand  for 4 h before testing;
- Eluate: no, suspensions were tested
- Differential loading: yes, 1000 + 10,000 mg/L
- Controls: Synthetic medium from groundwater
- Evidence of undissolved material (e.g. precipitate, surface film, etc): The test solutions remained turbid throughout the test, and starchy particles were observed on the bottom of the test vessels.

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

TEST ORGANISM
- Common name: Zebra fish
- Strain: --
- Source: M.B. Ruysbroek B.V./Noordvliet 159, Maassluis
- Age at study initiation (mean and range, SD):
- Length at study initiation (length definition, mean, range and SD): 2.1 +-0.1 cm
- Weight at study initiation (mean and range, SD): 0.07 +-0.01 g
- Food during test: no

ACCLIMATION
- Acclimation period: no data
- Type and amount of food: no data

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Post exposure observation period:

none

Hardness:

204 mg/L as CaCO3

Test temperature:

24.2 - 25.3

pH:

7.3 - 8.3

Dissolved oxygen:

7.3 - 8.5 mg/L

Salinity:

not applicable

Nominal and measured concentrations:

1000 and 10,000 mg/L SiO2 nominal (loading)

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Type (delete if not applicable): open
- Material, size, headspace, fill volume: glass beaker, 2 L, 1500 ml test suspension
- Aeration: slight aeration (no data)
- Type of flow-through (e.g. peristaltic or proportional diluter): --
- Renewal rate of test solution (frequency/flow rate): no
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): 2
- No. of vessels per control (replicates): 2
- No. of vessels per vehicle control (replicates): --
- Biomass loading rate: approx. 0.5 g fish/L


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: prepared from groundwater by addition of several salts
- Total organic carbon: 1.7 mg/L
- Alkalinity: -- no data
- Ca/Mg ratio: 1.83
- Conductivity: --


OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16 h light, 8 h dark
- Light intensity: -- no data


EFFECT PARAMETERS MEASURED (with observation intervals if applicable): survival. swimming behaviour, colour, respiratory function,
morphological and physiological changes that were visually observable at 24, 48, 72, and 96 h


TEST CONCENTRATIONS
- Spacing factor for test concentrations: 10
- Justification for using less concentrations than requested by guideline: limit test, expected low toxicity
- Range finding study
- Test concentrations: --
- Results used to determine the conditions for the definitive study: --

Duration:

96 h

Dose descriptor:

LL0

Effect conc.:

10 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks:

: 0/20 animals died

Details on results:

- Behavioural abnormalities: none
- Observations on body length and weight: none
- Other biological observations: no particular findings
- Mortality of control: none
- Other adverse effects control: none
- Abnormal responses: none

Results with reference substance (positive control):

not applicable

Reported statistics and error estimates:

not applicable

Sublethal observations / clinical signs:

After 96 h of exposure all animals were alive and their conditions (swimming behaviour, colour, respiratory function or any other visually observable morphological or behavioural criterion) was equal to that of the control animals.

Validity criteria fulfilled:

yes

Conclusions:

Ultrasil VN3 was not acutely toxic to Brachydanio rerio at loadings of 1000 and 10,000 mg/l.

Executive summary:

After 96 h of exposure all animals were alive and their conditions (swimming behaviour, colour, respiratory function or any other visually observable morphological or behavioural criterion) was equal to that of the control animals.

Reference 4

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

26 Oct. - 31 Oct. 1998

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: Water extract (water-accommodated fraction, WAF) by stirring corresponding suspensions for 24 h at 25 °C 
with subsequent filtration (paper) of the suspensions. Test solutions were then adjusted to pH 7.00.
- Differential loading: yes, 100, 1000, and 10,000 mg/L
- Controls: yes, untreated
- Chemical name of vehicle (organic solvent, emulsifier or dispersant): no
- Evidence of undissolved material (e.g. precipitate, surface film, etc): no data

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

TEST ORGANISM
- Common name: Zebra fish
- Strain: --
- Source: Aquafarm Ryba, D-27391 Zeven/Germany
- Age at study initiation (mean and range, SD):
- Length at study initiation (length definition, mean, range and SD): ~3 cm
- Weight at study initiation (mean and range, SD): no data
- Method of breeding:
- Feeding during test: no


ACCLIMATION
- Acclimation period:
- Acclimation conditions (same as test or not):
- Type and amount of food:
- Feeding frequency:
- Health during acclimation (any mortality observed):


QUARANTINE (wild caught)
- Duration:
- Health/mortality:

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Post exposure observation period:

none

Hardness:

no data

Test temperature:

24.9 - 25.1 °C

pH:

7.0 - 8.4

Dissolved oxygen:

7.2 - 8.0 mg O2/L

Salinity:

no data

Nominal and measured concentrations:

Loadings: 0, 100, 1000, and 10,000 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: aquarium
- Type: open
- Material, size, headspace, fill volume: 5-L volume, no further data
- Aeration: yes
- Renewal rate of test solution (frequency/flow rate): no
- No. of organisms per vessel: no data
- No. of animals per test concentration: 3 fish for 100 and 1000 mg/L, 7 fish for 10,000 mg/L
- No. of vessels per concentration (replicates):
- No. of vessels per control (replicates):
- No. of vessels per vehicle control (replicates): not relevant
- Biomass loading rate: no data


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: tap water (drinking water), corresponding to OECD-203 standard
no data available for the following parameters:
- Total organic carbon:
- Particulate matter:
- Metals:
- Pesticides:
- Chlorine:
- Alkalinity:
- Ca/Mg ratio:
- Conductivity:

- Culture medium different from test medium: no
- Intervals of water quality measurement: monthly

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: no data
- Light intensity: no data

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : behaviour, mortality


TEST CONCENTRATIONS
- Spacing factor for test concentrations: 10
- Range finding study: conducted with the highest loading as limit test

Duration:

96 h

Dose descriptor:

LL0

Effect conc.:

10 000 mg/L

Nominal / measured:

nominal

Basis for effect:

mortality (fish)

Remarks on result:

other: WAF of loading (filtered water extract)

Details on results:

No deaths occurred during testing. No particular findings.

Validity criteria fulfilled:

yes

Description of key information

No acute aquatic toxicity to fish study for magnesium silicate available.  Read-across from silicon dioxide and sodium aluminium silicate (NAS) studies show a low acute toxicity.