Tripotassium hexacyanoferrate

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:

09-Aug-2019 - 18-Sep-2019

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)

Version / remarks:

1992

Deviations:

no

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

During the limit test samples for possible analysis were taken from the limit concentration and the control.
Frequency: at t=0 h and t=96 h
Volume: 4.8 mL
Storage: Samples were stored in a freezer (≤-15°C) until analysis at the analytical laboratory of the Test Facility.
Additionally, reserve samples of 4.8 mL were taken from all test solutions for possible analysis. If not already used, these samples were stored in a freezer (≤-15°C) for a maximum of three months after delivery of the draft report, pending on the decision of the sponsor for additional analysis.

Vehicle:

no

Details on test solutions:

Preparation of test solutions started with the highest concentration of 100 mg/L. No other treatment than vigorous shaking was needed to completely dissolve the test item in medium. In the range-finding test, lower test concentrations were prepared by subsequent dilutions of the highest concentration in test medium. Coloration of test solutions increased with increasing test item concentrations from colorless to yellow. All test solutions were clear at the end of the preparation procedure.

Test organisms (species):

Cyprinus carpio

Details on test organisms:

TEST ORGANISM
- Common name: Carp (Cyprinus carpio, Teleostei, Cyprinidae) Linnaeus, 1758.
- Source: ‘De Haar Vissen’, Zodiac proefacc., Wageningen University and Research Centre, The Netherlands.
- Length at study initiation: Range-finding test: 2.8 ± 0.2 cm, Final test: 3.1 ± 0.2 cm.
- Weight at study initiation: Range-finding test: 0.21 ± 0.05 g, Final test: 0.29 ± 0.09 g.
- Characteristics: F1 from a single parent-pair bred in UV-treated water.

HOLDING
Quarantine/Acclimatisation: At least 12 days after delivery.
Holding Medium: The same medium as test medium.
Feeding: Daily with pelleted fish food (Essence 0.5-0.8 mm, Coppens International B.V., Helmond, The Netherlands).
Validity of batch: 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%.

FEEDING DURING TEST
No feeding during the test period.

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Hardness:

180 mg/L expressed as CaCO3

Test temperature:

20 - 21 °C

pH:

7.4 - 8.2

Dissolved oxygen:

6.5 - 8.3

Salinity:

Not applicable

Conductivity:

Not applicable

Nominal and measured concentrations:

Nominal concentrations: 100 mg/L, the regulatory limit concentration.
Measured concentration: Measured concentrations were at the level of nominal throughout the test (i.e. 101 - 103% relative to the nominal concentration).
Based on these results, effect parameters were expressed based on analytically confirmed nominal concentrations.
It should be noted that a response was measured in the control samples at the start and at the end of the test. The origin of the detected response is unknown. Since the acceptability criteria were met, and no adverse effects were observed in the control or the limit
concentration, this response has no impact on the study results or conclusions.

Details on test conditions:

TEST SYSTEM
- Test vessel: 10 litres, all-glass, containing 8 litres of test solution.
- Aeration: The test solutions were not aerated during the test.
- No. of organisms per vessel: 7
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1
- Loading rate: 0.25 g fish/litre, i.e. 7 fish per 8 litres of test medium.

TEST MEDIUM / WATER PARAMETERS :
- Test Medium: The following salts (analytical grade) were added to tap water purified by Reverse Osmosis (RO-water, GEON Waterbehandeling, Berkel-Enschot, The Netherlands):
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 / intensity: A daily low light photoperiod of 16 hours at a light intensity of approximately 7 lux.
- Intervals of water quality measurement: Dissolved oxygen content, pH and temperature: Daily in all vessels with surviving fish, beginning at the start of the test (day 0).

EFFECT PARAMETERS MEASURED (96h-LC50) :
- Mortality and other effects: 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.

TEST CONCENTRATIONS
- Spacing factor for test concentrations: a single concentration was tested (100 mg/L).
- Justification for using less concentrations than requested by guideline: Based on the results of the range-finding test.
- Range finding study
- Test concentrations: 0.1, 1.0, 1, 10 and 100 mg/L.
- Results used to determine the conditions for the definitive study: yes.

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

- Behavioural abnormalities: no behavioral abnormalities were observed in the control and the limit concentration throughout the test.
- Mortality of control: no

Results with reference substance (positive control):

- Under the conditions of the present test, PCP induced no lethal effects in carp at 0.10 mg/L.
- The 96h-LC50 for carp exposed to PCP was 0.15 mg/L (95 % confidence interval between 0.10 and 0.22 mg/L).
- This effect was already reached within 24 hours of exposure. -
- Results with reference substance valid?: Yes

Reported statistics and error estimates:

No LC50 could be calculated because the test item proved to be non-toxic (LC50 > maximum concentration).

Validity criteria fulfilled:

yes

Conclusions:

In conclusion, the 96h-LC50 for carp (Cyprinus carpio) exposed to Potassium Ferricyanide was beyond the range of concentrations tested, i.e. exceeded the analytically confirmed concentration of 100 mg/L.

Executive summary:

In a 96-h acute toxicity study conducted according to OECD guideline 203 and GLP principles, carp (Cyprinus carpio) were exposed to Potassium Ferricyanide under static conditions at the following nominal concentrations in a limit test: 0 (blank control) and 100 mg/L. The measured concentrations were at the level of nominal throughout the test (i.e. 101 - 103% relative to the nominal concentration). Based on these results, effect parameters were expressed based on analytically confirmed nominal concentration. The test substance did not induce visible or lethal effects in carp at 100 mg/L. The 96h-LC50 was >100 mg/L. The study is considered to be reliable without restrictions.

Description of key information

The 96-h LC50 for acute toxicity to fish was determined to be >100 mg/L (analytically confirmed nominal exposure concentration).

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

100 mg/L

Additional information

In a 96-h acute toxicity study conducted according to OECD guideline 203 and GLP principles, carp (Cyprinus carpio) were exposed to Potassium Ferricyanide under static conditions at the following nominal concentrations in a limit test: 0 (blank control) and 100 mg/L. The measured concentrations were at the level of nominal throughout the test (i.e. 101 - 103% relative to the nominal concentration). Based on these results, effect parameters were expressed based on analytically confirmed nominal concentration. The testsubstance did not induce visible or lethal effects in carp at 100 mg/L. The 96h-LC50 was >100 mg/L. The study is considered to be reliable without restrictions.