Dipotassium oxalate

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

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Qualifier:

according to guideline

Guideline:

other: DIN 38412 part15

Version / remarks:

1982

Principles of method if other than guideline:

- Principle of test: Determination of LC0 and LC100 value as measure of fish compatibility of the substance
- Short description of test conditions: First, the test item or the wastewater to be tested is filled into the aquarium in defined quantities so that the desired concentrations are obtained after filling up with test water to a final volume of 10L. The test solutions are mixed well; the ventilation is provided with the aid of a glass capillary during the entire experiment; the frequency of gassing is 1 to 3 bubbles per second. The oxygen content should not fall below 5 mg / L. The water temperature in the test should be (20 ± 1) ° C. In the same way, an experiment is carried out with water that has not been influenced by toxicity. A comparison test with a substance of known toxicity is also recommended. 10 fish are used per tank. The test time is 48 hours. Dead fish must be removed from the tank at least once a day.
- Parameters analysed / observed: Mortality

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

not specified

Details on test solutions:

The test item or the wastewater to be tested is filled into the aquarium in defined quantities so that the desired concentrations are obtained after filling up with test water to a final volume of 10L.

Test organisms (species):

Leuciscus idus melanotus

Details on test organisms:

TEST ORGANISM
- Common name: fish (orfe)
- Strain: Leuciscus idus melanotus [L.] = Idus idus melanotus HECK
- Source: specially bred in pond farms for experimental purposes
- Length at study initiation (length definition, mean, range and SD): 5 - 7 cm
- Weight at study initiation (mean and range, SD): 1.5 ± 0.3 g
- Maintenance of the brood fish: Maintenance
The fish are stored at (15 ± 5) °C in aerated drinking water that has been dechlorinated with activated charcoal, preferably under flow-through conditions. If static conditions are used, the water should be changed as often as possible. No more than 5 fish should be kept in 1L water. If a constant flow-through is not possible with short-term storage, the water in the pool must be sufficiently pumped around, filtered and exchanged. Long-term storage is not possible in this way.
10 to 20 mg of dry food for aquarium fish is added to each fish three times a week. The mortality during the keeping should not exceed 1% per week. The fish should be accommodated to the test conditions (temperature and composition of the test water) at least 3 days before the start of the test. They are fasted for two days before the test and during the test.


ACCLIMATION
- Acclimation period: at least three days
- Acclimation conditions (same as test or not): Same as test except for the temperature, flow-through conditions and the feeding frequency
- Type and amount of food during acclimation: 10 to 20 mg of dry food for aquarium fish is added to each fish three times a week.
- Feeding frequency during acclimation: Three times a week.
- Health during acclimation (any mortality observed): The mortality during the keeping should not exceed 1% per week.


FEEDING DURING TEST : No

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test temperature:

20 ± 1 °C

Dissolved oxygen:

at least 5 mg/L

Nominal and measured concentrations:

not specified

Details on test conditions:

TEST SYSTEM
- Test vessel:
aquaria
- Material, size, headspace, fill volume:
glass, 17L volume
- Aeration:
yes
- Type of flow-through (e.g. peristaltic or proportional diluter):
flow-through conditions were achieved by the aid of a glass pipette
- Renewal rate of test solution (frequency/flow rate):
n/a
- No. of organisms per vessel:
10
- No. of vessels per concentration (replicates):
n/a
- No. of vessels per control (replicates):
n/a
- No. of vessels per vehicle control (replicates):
n/a´

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: chlorine-free drinking water

- Total organic carbon: Ca/Mg-ion concentration 2.7 ± 0.5 mmol/L
- Ca/mg ratio: 4 to 1
acid capacity: 0.7 to 0.9 mmol/L
pH: 7 to 8
- Culture medium different from test medium:
No
- Intervals of water quality measurement:
n/a

OTHER TEST CONDITIONS
- Adjustment of pH:
yes

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
Mortality, intervals not reported, dead fish are removed after 24h at the latest

Reference substance (positive control):

not specified

Key result

Duration:

48 h

Dose descriptor:

LC0

Effect conc.:

250 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: Result from Juhnke (LWA NW)

Key result

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

325 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: Result from Juhnke (LWA NW)

Key result

Duration:

48 h

Dose descriptor:

LC100

Effect conc.:

400 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: Result from Juhnke (LWA NW)

Key result

Duration:

48 h

Dose descriptor:

LC0

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: Results from Lüdemann (WaBoLu Berlin)

Key result

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

160 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: Results from Lüdemann (WaBoLu Berlin)

Key result

Duration:

48 h

Dose descriptor:

LC100

Effect conc.:

250 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: Results from Lüdemann (WaBoLu Berlin)

Details on results:

not reported

Results with reference substance (positive control):

not reported

Validity criteria fulfilled:

not applicable

Conclusions:

In the present publication of Juhnke and Lüdemann (1978) 200 chemicals were tested in a short-term toxicity test to fish. Orfes (Leuciscus idus melanotus [L.] = Idus idus melanotus HECK) were used and exposed for 48h to test solutions made from chlorinated tapwater and the test item. The mortality was observed and the LC 50 value was given. Juhnke found a 48h LC50 of 325 mg/L whereas Lüdemann found the 48 h LC50 was 160 mg/L.

Executive summary:

In a 48 h acute toxicity study according to DIN 38412-15 (1982), orfes (Leuciscus idus melanotus) were exposed to Oxalic acid at different nominal concentrations under static conditions. The mortality of fish were determined and the respective LC0, LC50 and LC100 values were reported in a tabular form.

The 48 h LC50 was > 100 mg test material/L. Juhnke determined a LC50 of 325 mg/L and Rüdemann reported a LC50 value of 160 mg/L.  No visible sublethal effects were reported under the conditions of the present test. 

Reference 2

Endpoint:

short-term toxicity to fish

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Justification for type of information:

REPORTING FORMAT FOR THE ANALOGUE APPROACH

1. HYPOTHESIS FOR THE ANALOGUE APPROACH
This read-across hypothesis is based on transformation of the target and source substances to common compounds (scenario1 of the RAAF). The target substance Dipotassium oxalate is a salt of the free acid Oxalic acid. The source substance Dipotassium oxalate dissociates in aqueous solutions thereby forming Oxalic acid and potassium ions. Both constituents are ubiquitously occurring and also an essential part of the intermediary metabolism. Based on the available data especially repeated dose toxicity or genetic toxicity, reproductive toxicity for Oxalic acid and potassium ions it can be deduced that Oxalic acid is the toxicity determining constituent. Potassium ions are considered to be less toxic due to their role in cell metabolism and the well established mechanisms to maintain the cellular ion equilibrium.

2. SOURCE AND TARGET CHEMICAL(S) (INCLUDING INFORMATION ON PURITY AND IMPURITIES)
Source: Oxalic acid, CAS 144-62-7
Target: Dipotassium oxalate, CAS 583-52-8

3. ANALOGUE APPROACH JUSTIFICATION
Please refer to the justification for read-across attached to Chapter 13

4. DATA MATRIX
Please refer to the justification for read-across attached to Chapter 13

Reason / purpose for cross-reference:

read-across source

Duration:

48 h

Dose descriptor:

LC0

Effect conc.:

250 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: Result from Juhnke (LWA NW)

Key result

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

325 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: Result from Juhnke (LWA NW)

Duration:

48 h

Dose descriptor:

LC100

Effect conc.:

400 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: Result from Juhnke (LWA NW)

Duration:

48 h

Dose descriptor:

LC0

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: Results from Lüdemann (WaBoLu Berlin)

Key result

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

160 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: Results from Lüdemann (WaBoLu Berlin)

Duration:

48 h

Dose descriptor:

LC100

Effect conc.:

250 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: Results from Lüdemann (WaBoLu Berlin)

Validity criteria fulfilled:

not applicable

Conclusions:

In the present publication of Juhnke and Lüdemann (1978) 200 chemicals were tested in a short-term toxicity test to fish. Orfes (Leuciscus idus melanotus [L.] = Idus idus melanotus HECK) were used and exposed for 48h to test solutions made from chlorinated tapwater and oxalic acid. The mortality was observed and the LC 50 value was given. Juhnke found a 48h LC50 of 325 mg/L whereas Lüdemann found the 48 h LC50 was 160 mg/L.

Executive summary:

There are no data about dipotassium oxalate regarding the short-term toxicity to fish but based on the read-across approach according to the RAAF scenario 1, i.e. that the target substance and the source substance form similar breakdown products, data are available for the target substance oxalic acid.

In a 48 h acute toxicity study according to DIN 38412-15 (1982), orfes (Leuciscus idus melanotus) were exposed to Oxalic acid at different nominal concentrations under static conditions. The mortality of fish were determined and the respective LC0, LC50 and LC100 values were reported in a tabular form.

The 48 h LC50 was > 100 mg test material/L. Juhnke determined a LC50 of 325 mg/L and Rüdemann reported a LC50 value of 160 mg/L.  No visible sublethal effects were reported under the conditions of the present test. 

Thus, based on the available information, dipotassium oxalate is also not considered to be to be toxci to fish under the conditions of the test.

Description of key information

- study according to DIN 38412 part 15 (1982), 10 fish (orfe, Leuciscus idus melanotus) per concentration (control) are exposed to the test item in different concentrations (exact values not reported) for 48h in 10L aquaria at a temperature of 20°C ± 1°C and an oxygen content of at least 5 mg/L. Dead fish were removed from the aquaria at least once a day. The test was performed in two different laboratories published by either Junhke or Lüdemann, respectively. The LC0, LC50 and LC 100 values were obtained for oxalic acid:Juhnke: LC0 = 250 mg/L; LC50 = 325 mg/L; LC100 = 400 mg/L. Lüdemann: LC0 = 100 mg/L; LC50 = 160 mg/L; LC100 = 250 mg/L. The obvious difference between the values could not be explained, thus, for precautionary reasons the more restrictive values from Lüdemann et al. were used for risk assessment, read-across, oxalic acid, RL2

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Dose descriptor:

EC50

Effect concentration:

> 100 mg/L

Additional information

No data are available for the target substance dipotassium oxalate. There are, however, data for the structurally similar substance oxalic acid. A justification for read-across is attached to Chapter 13.

In a 48 h acute toxicity study according to DIN 38412-15 (1982), orfes (Leuciscus idus melanotus) were exposed to Oxalic acid at different nominal concentrations under static conditions. The mortality of fish were determined and the respective LC0, LC50 and LC100 values were reported in a tabular form.

The 48 h LC50 was > 100 mg test material/L. Juhnke determined a LC50 of 325 mg/L and Rüdemann reported a LC50 value of 160 mg/L.  No visible sublethal effects were reported under the conditions of the present test.