Potassium dicyanoargentate

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

yes

Remarks:

alternative culture medium

Principles of method if other than guideline:

The dilution water used for testing (and maintenance of stock cultures) was the EPA ‘Moderately Hard Water’ medium. This deviation from the OECD 202 Test Guideline is necessary as chelating agents, that are expected to interact with the test substance, are present in the Elendt’s M4 media recommended by the Guideline.

GLP compliance:

yes

Analytical monitoring:

yes

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: water flea
- Source: Brixham Environmental Laboratory continuous laboratory culture
- Age at study initiation (mean and range, SD): <24 hours old
- Feeding during test: No

Stock cultures were maintained in reconstituted water medium the same as the test dilution water at 20°C±2°C. Cultures were maintained in 1.6 L of medium in 2 L glass vessels with a photoperiod of 16 hours light: 8 hours dark with a 20 minute transition.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

153 mg CaCO3/L

Test temperature:

18.84-19.53°C

pH:

Range finding test: 8.29-8.50
Definitive test: 8.40-8.62

Dissolved oxygen:

Range finding test: 6.54-9.37 mg/L
Definitive test: 8.04-8.82 mg/L

Nominal and measured concentrations:

Range finding test
- Nominal: Control and 0.001, 0.01, 0.1, 1.0, 10 and 100 mg/L potassium dicyanoargentate
Definitive test
- Nominal: Control, 0.0043, 0.0094, 0.021, 0.045 and 0.10 mg/L potassium dicyanoargentate

Details on test conditions:

TEST SYSTEM
- Test vessel: 100 mL glass beaker covered with loose fitting glass lids
- Fill volume: 80 mL
- Aeration: No
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 2 in range finding test, 4 in definitive test
- No. of vessels per control (replicates): 2 in range finding test, 4 in definitive test

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: US EPA(1994) 'Moderately Hard Water'
- Total organic carbon: 2.43 mg/L
- Metals:Aluminium <10 µg/L
Arsenic <1.00 µg/L
Boron <100 µg/L
Cadmium <0.1 µg/L
Chromium <0.5 µg/L
Cobalt <1 µg/L
Copper <1 µg/L
Iron <30 µg/L
Lead <2 µg/L
Manganese <10 µg/L
Mercury <0.0100 µg/L
Nickel <1 µg/L
Silver <1 µg/L
Zinc <5 µg/L
- Pesticides:
Highest organophosphorous pesticides <0.02 μg/L
Highest organochlorine pesticides <0.05 μg/L
- Highest PCB <0.01 μg/L
- Alkalinity: 97 mg CaCo3/L

OTHER TEST CONDITIONS
- Photoperiod: 16 hours light: 8 hours dark with 20 minutes transition

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

0.05 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: Potassium dicyanoargentate concentration calculated from measured silver concentration. 95% CL 0.042-0.062 mg/L

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

0.022 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: Potassium dicyanoargentate concentration calculated from measured silver concentration. 95% CL 0.016-0.03 mg/L

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

0.058 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95%CL 0.050-0.070 mg/L

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

0.033 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95%CL 0.026-0.043 mg/L

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

0.002 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: Potassium dicyanoargentate concentration calculated from measured silver concentration.

Duration:

48 h

Dose descriptor:

LOEC

Effect conc.:

0.005 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: Potassium dicyanoargentate concentration calculated from measured silver concentration.

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

0.004 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

LOEC

Effect conc.:

0.009 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

EC100

Effect conc.:

0.095 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: Potassium dicyanoargentate concentration calculated from measured silver concentration.

Duration:

48 h

Dose descriptor:

EC100

Effect conc.:

0.1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

The mean measured concentration of silver during the definitive test ranged from 43 to 95% of the nominal silver concentration, the measured silver concentration was used to calculate the potassium dicyanoargentate concentration. Results are reported using both the calculated and nominal potassium dicyanoargentate concentrations.

Reported statistics and error estimates:

The 24 and 48-hour EC50 values and their 95% confidence intervals were calculted using Stephan's method.

Validity criteria fulfilled:

yes

Conclusions:

The 48-hour EC50 is 0.022 mg/L (measured) and 0.033 mg/L (nominal).

Executive summary:

A 48-hour static test was carried out according to OECD 202 test guideline, with deviation on the test medium, to determine the acute toxicity of potassium dicyanoargentate to Daphnia magna (Brixham 2012a). Four replicate tests at five concentrations of potassium dicyanoargentate and a control were performed. The 48-hour EC50, EC100, NOEC and LOEC are reported based on measured and nominal concentrations. The 48-hour EC50 is 0.022 mg/L (measured) and 0.033 mg/L (nominal).

Description of key information

The 48-hour EC50 for potassium dicyanoargentate to Daphnia magna is 0.022 mg/L (measured).

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

0.022 mg/L

Additional information

A 48-hour static test was carried out according to OECD 202 test guideline, with deviation on the test medium, to determine the acute toxicity of potassium dicyanoargentate to Daphnia magna (Brixham 2012a). Four replicate tests at five concentrations of potassium dicyanoargentate and a control were performed. The 48-hour EC50, EC100, NOEC and LOEC are reported based on measured and nominal concentrations. The 48-hour EC50 for potassium dicyanoargentate to Daphnia magna is 0.022 mg/L (measured).