Strontium hydrogen phosphate

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:

24-28 February 2014

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: The study was conducted according to the OECD 203 Guideline and complied with the principles of GLP.

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

Qualifier:

according to guideline

Guideline:

ISO 7346-1 (Determination of the Acute Lethal Toxicity of Substances to a Freshwater Fish [Brachydanio rerio Hamilton-Buchanan (Teleostei, Cyprinidae)] - Part 1: Static Method)

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: Guidance document on aquatic toxicity testing of difficult substances and mixtures, OECD series on testing and assessment number 23, December 14, 2000.

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

During the test singular 4.8 mL samples for possible analysis were taken from the limit concentration and the control at t=0 h, t=24 h and t=96 h. In addition, the filter containing undissolved residue was retained for possible analysis.

Vehicle:

no

Details on test solutions:

Preparation of test solution started with a loading rate of 100 mg/L applying a 2-day period of magnetic stirring followed by a filtration through a 0.45 µm membrane filter (rc55, Whatman). The obtained Water Soluble Fraction (WSF) was used as the limit concentration. The final test solution was clear and colourless.

Test organisms (species):

Cyprinus carpio

Details on test organisms:

TEST ORGANISM
- Common name: Carp
- Strain: Linnaeus
- Source: Zodiac, proefacc, "De Haar Vissen", Wageningen University and Research Centre, The Netherlands.
- Length at study initiation (length definition, mean, range and SD): 2.5 ± 0.1 cm (mean of ten fish)
- Weight at study initiation (mean and range, SD): 0.51 ± 0.09 g (mean of ten fish)
- Method of breeding: F1 from a single parent-pair bred in UV-treated water
- Feeding during test: No feeding from 24 hours prior to the test and during the total test period

ACCLIMATION
- Acclimation period: At least 12 days after delivery; following a 48-hour settling-in period the fish were allowed to acclimatise to the test medium without test substance for at least seven days
- Acclimation conditions (same as test or not): yes
- Type and amount of food: pelleted fish food (Cyprico Crumble Excellent (300-500 um), Coppens International bv, Helmond, The Netherlands)
- Feeding frequency: daily
- Health during acclimation (any mortality observed): In the batch of fish used for the test, mortality during the seven days prior to the start of the test was less than 5%.

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Post exposure observation period:

None

Hardness:

180 mg CaCO3/L

Test temperature:

21-22 ºC

pH:

7.5-7.8

Dissolved oxygen:

6.6-9.5 mg O2/L

Salinity:

Not applicable.

Nominal and measured concentrations:

The actual concentration was 12 mg Sr/l at the start of the test in the WSF prepared at a loading rate of 100 mg/l and remained stable during the exposure (99-105% of initial). This concentration was considered to be the maximum soluble concentration in the test medium.

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Material, size, headspace, fill volume: 15 litres, all-glass, containing 14 litres of test solution
- Aeration: none
- No. of organisms per vessel: 7
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1
- Biomass loading rate: 0.26 g fish/litre, i.e. 7 fish per 14 litres of test medium

TEST MEDIUM / WATER PARAMETERS
- Test medium: Adjusted ISO medium with a hardness of 180 mg CaCO3 per litre and a pH of 7.7 ± 0.3
- Source/preparation of dilution water: RO-water (tap-water purified by reverse osmosis; GEON Waterbehandeling, Berkel-Enschot, The Netherlands) with the following composition:
CaCl2.2H2O 211.5 mg/L
MgSO4.7H2O 88.8 mg/L
NaHCO3 46.7 mg/L
KCl 4.2 mg/L


OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16 hours photoperiod daily
- Light intensity: not stated

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : mortality at 3, 24, 48, 72 and 96 hours following the start of exposure. In addition, every afternoon from day 0 and every morning from day 1 to observe for any dead or severely distressed fish.
Dissolved oxygen content, pH and temperature: daily in all vessels with surviving fish, beginning at the start of the test (day 0).

TEST CONCENTRATIONS
- Test concentrations: WSF prepared at a loading rate of 100 mg/l

Reference substance (positive control):

yes

Remarks:

pentachlorophenol (PCP)

Duration:

96 h

Dose descriptor:

LC50

Basis for effect:

mortality (fish)

Remarks on result:

other: LC50 > maximum soluble concentration in test medium

Details on results:

No mortality or other clinical effects were observed in the control and the WSF prepared at 100 mg/l.
The actual concentration was 12 mg Sr/l at the start of the test in the WSF prepared at a loading rate of 100 mg/l and remained stable during the exposure (99-105% of initial). This concentration was considered to be the maximum soluble concentration in the test medium.

Acceptability of the test
1. No mortality was observed in the control at the end of the test.
2. Test conditions were maintained constant throughout the test.
3. The dissolved oxygen concentration has been at least 60% of the air saturation value throughout the test (>5 mg/l at 22°C).
4. The concentrations of the substance being tested have been at least 80% of the initial concentration throughout the test.

Results with reference substance (positive control):

The 96h-LC50 for carp exposed to PCP was 0.24 mg/l.

Validity criteria fulfilled:

yes

Conclusions:

The 96h-LC50 exceeded the maximum solubility of SrHPO4 in the test medium.

Executive summary:

A 96-h Acute Toxicity study in carp was performed with SrHPO4 according to OECD 203 and in compliance with GLP principles. The test substance solution was prepared as a water soluble fraction of a loading rate of 100 mg/L. The actual measured concentration of the WSF was 12 mg Sr/L at the start of the test and remained stable during exposure. No effects were observed and thus the 96h-LC50 was considered to exceed the maximum solubility of the test substance in medium.

Description of key information

A 96-h Acute Toxicity study in carp was performed with SrHPO4 according to OECD 203 and in compliance with GLP principles. The test substance solution was prepared as a water soluble fraction of a loading rate of 100 mg/L. Preparation of test solution started with a loading rate of 100 mg/L applying a 2-day period of magnetic stirring followed by a filtration through a 0.45 µm membrane filter. The actual measured concentration of the WSF was 12 mg Sr/L at the start of the test and remained stable during exposure. No effects were observed and thus the 96h-LC50 was considered to exceed the maximum solubility of the test substance in medium.

Additional information

Key value for CSA: 96h-LC50 is > the maximum solubility of the test substance in medium.