Strontium neodecanoate

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2015-07-06 to 2015-07-10

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study including analytical moitoring

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.1 (Acute Toxicity for Fish)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

signed 2011-02-07

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material (migrated information):
not applicable

Analytical monitoring:

yes

Details on sampling:

- Concentrations: The control media and each test concentration were sampled before the test. Additionally, the aged test solution at test end was sampled from each vessel.
- Sampling method: Exactly 20 mL of aqueous samples were taken.
- Sample storage conditions before analysis: Solutions were examined for soapy bubbles or particles floating on the surface. The samples were filtered (0.22 μm polyether sulphone membrane syringe filter) at room temperature (20-25°C), transferred into disposable 50 mL polyethylene vials (Scintillation vials, Sarstedt, Nuembrecht, Germany), acidified with 200 μL of conc. nitric acid (final concentration 1% HNO3) and stored refrigerated until further analysis.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: stock solution (800 mg/L) was prepared and stirred for 68 h at 700 rpm, followed by sonification for 25 minutes. The solution was filtered, i.e., the insoluble parts were separated from the aqueous phase, and sterilised by filtration through a 0.2 μm filter (Sartolab 150 Vacuum- PES-membrane filter (PES: Polyether sulfone)). Individual test solutions are prepared by diluting the filtered stock solution.
- Controls: consisted of dilution water. Purified local tap water was used as dilution water.

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

TEST ORGANISM
- Common name: zebrafish
- Species: Danio rerio (Teleostei, Cyprinidae)
- Source: test facility breed
- Length at study initiation (length definition, mean, range and SD): 2.0 ± 1.0 cm
- Feeding during test: Fish were not fed during the test as well as 24 h before the test start.

ACCLIMATION
- Acclimation period: at least 12 days prior to the test
- Acclimation conditions (same as test or not): fish were held under equivalent water quality and illumination conditions to those proposed for use in the test.
- Type and amount of food: fish were fed throughout the holding period with live brine shrimp (Artemia spp.) nauplii and ground flake food TetraMinR (Tetra Werke, Melle, Germany)
- Feeding frequency: once daily
- Health during acclimation (any mortality observed): only healthy fish without diseases and abnormalities were used in the study. Mortality of the batch was less than 5 % in the week preceding the start of the study.
- Purified local tap water was used as holding water.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Hardness:

total hardness (holding and dilution water): 1.1 mmol/L

Test temperature:

23.1 °C

pH:

between 8.41 and 8.70

Dissolved oxygen:

oxygen saturation: 88 to 97%

Salinity:

not applicable

Nominal and measured concentrations:

Nominal added strontium neodecanoate concentration: 46.1, 72.8, 117.1, 187.2, and 299.7 mg Strontium neodecanoate/L (pure substance, corresponding to 8.7, 13.7, 22.0, 35.2, 56.3 mg Sr/L).
Measured concentrations at the start and end of 96-h exposure period range from 100 to 118% of nominal test concentrations.

Details on test conditions:

TEST SYSTEM
- Test vessel: Full glass aquaria of 12 L nominal volume - filled with 10 L medium
- Aeration: slightly aerated via a glass capillary
- No. of organisms per vessel: 7 fish
- No. of vessels per concentration (replicates): 1 (no replicates)
- No. of vessels per control (replicates): 1 (no replicates
- No. of vessels per vehicle control (replicates): None
- The mean weight of fish resulted in a loading of 0.01 g/L test medium

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: The tap water was sourced from the Schmallenberg district water production plants, mostly fed by small springs and percolation, and meets the hardness and pH recommendations of the OECD-Guideline 203. The purification included filtration with activated charcoal, passage through a lime-stone column and aeration until oxygen saturation. To avoid copper contamination, plastic water pipes are used by the test facility.
- Total organic carbon: 0.38 mg/L
- Total hardness: 1.1 mmol/L
- nitrate: 8.0 mg/L
- nitrite: 0.007 mg/L
- ammonium: <0.01 mg/L
- phosphate: 0.54 mg/L
- Chlorine: <0.02 mg/L
- Alkalinity: 2.0 mmol/L
- Ca/mg ratio: 10
- Conductivity: 235 µS/cm
- cadmium: <0.490 µg/L*
- chromium: <0.897 µg/L**
- copper: <4.63 µg/L**
- iron: <1.47 µg/L*
- manganese: <0.449 µg/L*
- nickel: <2.31 µg/L**
- lead: <1.17 µg/L*
- zinc: <0.717 µg/L*
- Culture medium different from test medium: NO
*<: value below the respective LOD; **<: value below the respective LOQ

OTHER TEST CONDITIONS
- Adjustment of pH: The pH of solutions in test vessel was not affected by the test substance and remained constant over the course of study.
- Photoperiod: 12 light / 12 dark

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
Mortality and abnormal behaviour were recorded after 3 h, 24 h, 48 h, 72 h and 96 h. Dead animals – if present – were eliminated from the vessels as soon as they were discovered.

TEST CONCENTRATIONS
- Range finding study: No effects at nominal concentrations of 1.01, 10.1 and 101 mg Strontium neodecanoate/L
- Test concentrations: nominal added strontium neodecanoate concentration: 46.1, 72.8, 117.1, 287.2, and 299.7 mg Strontium neodecanoate/L

Reference substance (positive control):

no

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 299.7 mg/L

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

mortality (fish)

Remarks on result:

other: (analytically verified)

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

>= 299.7 mg/L

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

mortality (fish)

Remarks on result:

other: (analytically verified)

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 56.34 mg/L

Nominal / measured:

nominal

Conc. based on:

element

Remarks:

Sr

Basis for effect:

mortality (fish)

Remarks on result:

other: concentration analytically verified

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

>= 56.34 mg/L

Nominal / measured:

nominal

Conc. based on:

element

Remarks:

Sr

Basis for effect:

mortality (fish)

Remarks on result:

other: concentration analytically verified

Details on results:

- Physical/Phatological symptoms and changes in behaviour:
Neither significant signs of disease nor stress such as discolouration or abnormal behaviour were observed up to a concentration of 187.2 mg strontium neodecanoate/L (nominal, pure substance). At the highest tested concentration (299.7 mg strontium neodecanoate/L (nominal, pure substance), a darker colouration was observed in three fish, six fish remained mainly at the bottom of the vessel and one fish stayed mainly near the water surface. The activity of the fish at the highest tested concentration was after 24 h lower than that of fish in other treatments or in the control. After 96 h, the fish were more active than after 24 h but still not as active as in other treatments or in the control.
- Range finding study: In the non-GLP range finding test with nominal concentrations of 1.01, 10.1 and 101 mg strontium neodecanoate/L. Effects on the mortality of fish could not be observed during the range-finder test at any of the tested concentrations.
- Mortality: Mortality of the fish was not observed in any of the treatments.

Results with reference substance (positive control):

A reference item was not tested as it is not required by the guideline.

Reported statistics and error estimates:

No fish died during the study, i.e., mortality was not observed in the control or in any treatment, including the highest test concentration. Therefore, a test statistic is not needed.

Validity criteria fulfilled:

yes

Conclusions:

Acute toxicity of strontium neodecanoate to Danio rerio was not observed in a 96-h OECD 203 test; the NOEC amounts to ≥ 299.7 mg strontium neodecanoate per litre whereas the respective LC50 is estimated with > 299.7 mg per litre (all nominal, analytically verified) the highest concentration tested.

Description of key information

Strontium neodecanoate has a low potential for acute toxicity to fish since mortality was not observed after 96 h up to 299.7 mg/L in an acute toxicity test.

Additional information

In a GLP-conform OECD 203 test, mortality was not observed after 96 h incubation up to the highest tested concentration of 299.7 mg strontium neodecanoate/L (nominal, analytical verified) [Teigeler, 2015].