Disodium wolframate

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

Study period:

2008-09-25 to: 2009-03-13

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

Well documented, scientifically sound study conducted in accordance to GLP and OECD guideline 203 with no deviation to the protocol.

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

no

GLP compliance:

yes

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material (migrated information):
no data

Analytical monitoring:

yes

Details on sampling:

- Concentrations: 0 (control), 13, 25, 50, 100, and 200 mg/L; A volume of 10 mL was collected from each control and test substance replicate at 0 and 96 hours and transferred to a culture tube.
- Sampling method: 0.05 mL aliquot of each sample was taken, diluted if necessary with 2% HNO3, capped and shaken to mix.
- Sample storage conditions before analysis: Room temperature

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: 7.5075 g of sodium tungstate dihydrate was added to a 21-L glass jar and bringing the jar to a volume of 15,000 mL with blended freshwater. Appropriate aliquots of the primary standard were diluted with 15 L of dilution water to prepare final test concentrations of 13, 25, 50, 100, and 200 mg total product/L. The control solution consisted only of dilution water.

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

TEST ORGANISM
- Common name: Zebrafish
- Source: Osage Catfisheries, Osage Beach, Missouri
- Age at study initiation (mean and range, SD): Not specified
- Length at study termination (length definition, mean, range and SD): 28-31 mm; mean 30 ± 1.2 mm (Controls only)
- Weight at study termination (mean and range, SD): 0.194-0.408 g; mean 0.276 ± 0.0664 g (Controls only)
- Feeding during test
- Frequency: Not fed during test, or one day prior

ACCLIMATION
- Acclimation period: 5 days
- Acclimation conditions (same as test or not): Temperature adjusted for test
- Type and amount of food: Salmon starter, flake food, and brine shrimp
- Feeding frequency: Daily
- Health during acclimation (any mortality observed): No mortality observed in 14 days prior to testing.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Post exposure observation period:

None

Hardness:

140 mg/L CaCO3

Test temperature:

23 ± 1 degrees C

pH:

8.0-8.3 SU

Dissolved oxygen:

6.7-8.3 mg/L (82 to 101% sat)

Salinity:

Not applicable

Nominal and measured concentrations:

Nominal- 0 (control), 13, 25, 50, 100, and 200 mg/L.
Mean calculated-

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Type (delete if not applicable): closed
- Material, size, headspace, fill volume: 21 L glass jars, covered with plastic Petri dishes; 15 L test solution.
- Aeration: None
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1
- Biomass loading rate: 0.18 g fish tissue/L test solution

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Moderately hard freshwater made with naturally hard well water blended with well water demineralized by reverse osmosis, total hardness of 130-160 mg/L CaCO, passed through a sediment filter prior to use.
- Metals: B-0.415 mg/L, Ca-83.1 mg/L, Mg- 33.1 mg/L, K-7.93 mg/L, Na-32.2 mg/L; all others below DL.
- Pesticides: Below DL
- Alkalinity: 150 mg/L CaCO3
- Conductivity: 328 uS
- Intervals of water quality measurement: Daily

OTHER TEST CONDITIONS
- Adjustment of pH: None
- Photoperiod: 16h light/ 8h dark, with 30 min simulated dawn and dusk periods
- Light intensity: 542 lux at initiation of the definitive test as measured with a LI COR Model LI-189 light meter equipped with a photometric sensor.

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : Mortality, 24h

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 2x
- Range finding study: Other studies indicated a low potential for toxicity to aquatic organisms; Therefore, a range finding study was not performed. Definitive testing was performed at a level that exceeds the guideline-required maximum, 100 mg/L for this test.

Reference substance (positive control):

no

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 200 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: No mortality in any control or test solution

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 181 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Remarks:

based on mean calculated concentrations of sodium tungstate

Basis for effect:

mortality (fish)

Remarks on result:

other: No mortality in any control or test solution

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

200 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

behaviour

Remarks on result:

other: Lack of mortality and sublethal effects

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

>= 181 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Remarks:

based on mean calculated concentrations of sodium tungstate

Basis for effect:

behaviour

Remarks on result:

other: Lack of mortality and sublethal effects

Details on results:

Biological Results:
After 96 hours of exposure, there was no mortality in the 0 (control) or any of the test substance treatments. There were no sublethal observations during the exposure. The estimated 24-, 48-, 72-, and 96-hour LC50 values for zebrafish exposed to sodium tungstate dihydrate were >200 mg/L, the highest concentration tested. Since there was no partial response, the 96-hour slope of the concentrations-response line could not be calculated from the probit analysis. The 96 hour no-observed-effect concentration (NOEC) was 200 mg/L based on the lack of mortality and sublethal effects atthis and lower test substance concentrations.

Reported statistics and error estimates:

Estimates of LC50 values and their 95% confidence limits were calculated using the probit method and Trimmed Spearman-Karber method. When the p value for Goodness of Fit was >0.05 and there was no other evidence of questionable convergence, the probit method was selected for reporting. When this criterion was not achieved, the Trimmed Spearman-Karber method was selected for reporting. The no observed-effect concentration (NOEC) was determined based on the absence of any mortality or sublethal effects.

Conclusions:

Based on nominal concentrations, the estimated 96 hour LC50 value for zebrafish exposed to sodium tungstate dihydrate was >200 mg/L, the highest concentration tested. The 96 hour slope of the concentrations-response line could not be calculated. The 96-hour no-observed-effect concentration (NOEC) was 200 mg/L, based on the lack of mortality and sublethal effects at this and the lower concentrations.

Reference 2

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

Guideline study. No analytical confirmation of test concentrations. Few details regarding test solution preparation.

Reason / purpose for cross-reference:

reference to other study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Qualifier:

according to guideline

Guideline:

OECD Guideline 204 (Fish, Prolonged Toxicity Test: 14-day Study)

GLP compliance:

not specified

Analytical monitoring:

no

Details on sampling:

N/A

Vehicle:

no

Test organisms (species):

Poecilia reticulata

Details on test organisms:

TEST ORGANISM
- Common name: Guppy
- Strain: No data
- Source: Ward's Natural Science
- Age at study initiation (mean and range, SD): > 4 weeks
- Length at study initiation (length definition, mean, range and SD): No data
- Weight at study initiation (mean and range, SD): No data
- Method of breeding: purchased
- Feeding during test
- Food type: Tetra Min flakes
- Amount: No data
- Frequency: Not fed during 96 h test, twice daily during 14 day test.


ACCLIMATION
- Acclimation period: 4 weeks
- Acclimation conditions (same as test or not): yes
- Type and amount of food: Tetra Min flakes, ad libitum
- Feeding frequency: twice daily
- Health during acclimation (any mortality observed): No mortality 7 days prior to the experiment

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

14 d

Remarks on exposure duration:

96 h test, followed by up to 14 day test with fish that survived the 96 hour one.

Post exposure observation period:

None

Hardness:

no data

Test temperature:

23.5 +/- 0.3 deg C

pH:

7.43-8.1 SU

Dissolved oxygen:

3.7-5.49 mg/L

Salinity:

not applicable

Nominal and measured concentrations:

Nominal- Control, 0.75, 1.5, 2.5, 3.75, 5.0, 7.5, and 9.0 g/L

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Type: open
- Material, size, headspace, fill volume: Plastic 8 L aquaria
- Aeration: none
- Type of flow-through (e.g. peristaltic or proportional diluter): semi-static
- Renewal rate of test solution (frequency/flow rate): Initial at 96 hours and then fish placed in entirely new aquaria with fresh solution every 4 days.
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): 2
- No. of vessels per control (replicates): 4
- No. of vessels per vehicle control (replicates): N/A
- Biomass loading rate: average 0.37 g/L


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Local tap water, aged and aerated 3 days before use
- Total organic carbon: No data
- Particulate matter: No data
- Metals: No data
- Pesticides: No data
- Chlorine: No data
- Alkalinity: N/A
- Ca/mg ratio: No data
- Conductivity: 0.399-5.29 mS/cm
- Culture medium different from test medium: no
- Intervals of water quality measurement: No data


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


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : Mortality, 24 h


TEST CONCENTRATIONS
- Spacing factor for test concentrations: 2
- Justification for using less concentrations than requested by guideline: N/A
- Range finding study
- Test concentrations: not specified
- Results used to determine the conditions for the definitive study: yes

Reference substance (positive control):

no

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

3.71 g/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

2.06 other: g W/L

Nominal / measured:

nominal

Conc. based on:

other: tungsten concentration

Basis for effect:

mortality (fish)

Duration:

14 d

Dose descriptor:

LC50

Effect conc.:

1.54 g/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

14 d

Dose descriptor:

LC50

Effect conc.:

0.86 other: g W/L

Nominal / measured:

nominal

Conc. based on:

other: tungsten concentration

Basis for effect:

mortality (fish)

Details on results:

- Behavioural abnormalities: Fish exposed to test substance were slower, and remained predominantly at the bottom of the tank, as compared to controls
- Observations on body length and weight: No data
- Other biological observations: No data
- Mortality of control: No data
- Other adverse effects control: No data
- Abnormal responses: No data
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: No data
- Effect concentrations exceeding solubility of substance in test medium: No data

Results with reference substance (positive control):

N/A

Reported statistics and error estimates:

LC50 values and confidence intervals were calculated individually for each exposure period with the Probit Analysis .Program version 1.5. NOEC and LOEC values were evaluated using ANOVA and one-sided Dunnett's test, Version 1.5. The 5% statistical significance level was accepted for statistical results.

Sublethal observations / clinical signs:

Additional results:

-Wet weight BCF for the test substance was calculated as 0.29 +/- 0.94 L/kg

-Dry weight BCF for the test substance was calculated as 1.57 +/- 0.5 L/kg

Validity criteria fulfilled:

not specified

Conclusions:

The 96 hour LC50 of sodium tungstate to P.reticulata was found to be 3.71 g sodium tungstate/L. The 14 day LC50 was found to be 1.54 g sodium tungstate/L. Confidence intervals were not presented in g/L. The dry weight bioconcentration factor was calculated as 1.57 +/- 0.5 L/kg.

Executive summary:

N/A

Description of key information

The 96-hr LC50 for Danio rerio found in a test conducted according to OECD 203, under GLP standards, and with analytical verification of the test concentrations was >181 mg sodium tungstate/L. This finding was supported by another test conducted with similar methodology, which found a 96-hr LC50 of 3.71 g sodium tungstate/L for Poecilia reticulata.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

3.71 g/L