Sodium pyruvate

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

Study period:

from 2018-04-10 to 2018-05-10

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)

Version / remarks:

2004

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Version / remarks:

2008

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPPTS 850.1010 (Aquatic Invertebrate Acute Toxicity Test, Freshwater Daphnids)

Version / remarks:

1996

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

Four replicate samples (3 mL per replicate) were taken from the test solution (100 mg/L) and from the control at the start and at the end of the test.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
The test solution used in the test was prepared by mechanical dispersion without using of any solubilising agent.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Waterflea
- Strain/clone: Straus
- Source: Laboratory of Hydrobiology (Central Agricultural Office, Directorate of Plant-, and Soil Protection) 2100 Gödöllő, Kotlán S. u. 3. Hungary
- Age at test start: Less than 24 hours old
- Feeding during test: no

ACCLIMATION
- Acclimation period: no, breeding conditions same as test conditions

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Post exposure observation period:

No

Hardness:

249 mg/L (as CaCO3)

Test temperature:

20.1 - 20.5 °C

pH:

8.02 – 8.30

Dissolved oxygen:

7.09 – 7.27 mg/L

Salinity:

Not applicable

Conductivity:

Not measured

Nominal and measured concentrations:

Nominal concentration: 100 mg/L
Measured concentration: 97.8 mg/L at the start and 102.9 mg/L at the end of the test (98 and 103 % of the nominal respectively)

Details on test conditions:

TEST SYSTEM
- Test vessel: Glass beakers
- Material, fill volume: glass, 40 mL medium
- Aeration: no
- No. of organisms per vessel: 5
- No. of vessels per concentration: 4
- No. of vessels per control: 4

TEST MEDIUM / WATER PARAMETERS
- Preparation of dilution water: ISO medium, according to OECD 202

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16 hours light (artificial illumination) and 8 hours darkness
- Light intensity: 651 lux

EFFECT PARAMETERS MEASURED
- Visual observation of immobility or mortality after 24 and 48 h of exposure

RANGE-FINDING STUDY
- Test concentrations: 100 mg/L nominal concentration
- Results used to determine the conditions for the definitive study: No immobility or any sub-lethal effect was detected in the test concentration and in the control group during the 48-h exposure period.

Reference substance (positive control):

yes

Remarks:

Potassium dichromate (K2Cr2O7)

Duration:

48 h

Dose descriptor:

EC10

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

other: EC20

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

LOEC

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

- Behavioural abnormalities: no
- Observations on body length and weight: no
- Other biological observations: no
- Mortality of control: no
- Other adverse effects control: no
- Abnormal responses: no
- Any observations that might cause a difference between measured and nominal values: no
- Effect concentrations exceeding solubility of substance in test medium: no

VALIDITY OF THE STUDY
- The immobilisation rate of the introduced Daphnia did not exceed 10 %. Immobility was not observed in the untreated control and no Daphnia were trapped at the water surface or showed any sign of stress.
- The dissolved oxygen concentration at the end of the test was more than 3 mg/L in control and test vessels.

All validity criteria were within acceptable limits and therefore the study was considered as valid.

Results with reference substance (positive control):

Date of the last study with reference item Potassium dichromate was: 28 February – 01 March 2018. The 24h EC50: 1.41 mg/L, (95 % confidence limits: 1.19 – 1.68 mg/L).

Reported statistics and error estimates:

A limit test was performed and toxic effects were not observed, therefore statistical analysis was not performed. The NOEC, LOEC and ECx values of the test item were determined directly from the raw data.

Table 1: Immobilisation of test animals

Test group	Replicate	Number of treated animals	Number of immobilised animals
			24 h	48 h
Control	1	5	0	0
	2	5	0	0
	3	5	0	0
	4	5	0	0
100 mg/L (nominal)	1	5	0	0
	2	5	0	0
	3	5	0	0
	4	5	0	0

Table 2: Test item concentration measured

Sampling date	Nominal concentration (mg Test Item/L)	Mean of the measured concentrations (mg Test Item/L)	Measured concentration in percentage of the nominal	Relative Standard Deviation [%] (n=4)
10 April 2018	100	97.8	98	1
12 April 2018	100	102.9	103	4

The test item was not detected in the control samples.

Validity criteria fulfilled:

yes

Conclusions:

The acute immobilisation of the test item to Daphnia magna was determined according to OECD guideline 202, EU Method C.2 and EPA OPPTS 850.10110 in compliance with GLP principles. The EC50 value after 48 h was determined to be > 100 mg/L (nominal).

Executive summary:

The acute immobilisation of the test item to Daphnia magna (STRAUS) was determined in compliance with GLP criteria according to OECD Guideline 202, EU Method C.2 and EPA OPPTS 850.1010. The study was conducted under static conditions over a duration of 48 hours. 20 test organisms were exposed to the test concentration and control. The test item solutions were clearly dissolved throughout exposure. The nominal test item concentration was: 100 mg/L. A reference test was carried out with potassium dichromate as reference item at least twice a year and the reference toxicity determined. The EC50 -value of the reference item at 1.41 mg/L after 24 h was within the prescribed concentration range of 1.0 to 2.5 mg/L according to AQS, DIN Guideline 38412 L 30. Water quality parameters of pH-value and dissolved oxygen concentration measured at 0 and 48 h were determined to be within the acceptable limits.The validity criteria of the test guideline were fulfilled. The EC50 value and EC10 value were determined to be above 100 mg/L after 48 h.

Description of key information

The 48-h EC50 of the substance was determined to be > 100 mg/L (nominal).

Additional information

The acute immobilisation of the test item to Daphnia magna (STRAUS) was determined in compliance with GLP criteria according to OECD Guideline 202, EU Method C.2 and EPA OPPTS 850.1010. The study was conducted under static conditions over a duration of 48 hours. 20 test organisms were exposed to the test concentration and control. The test item solutions were clearly dissolved throughout exposure. The nominal test item concentration was: 100 mg/L. A reference test was carried out with potassium dichromate as reference item at least twice a year and the reference toxicity determined. The EC50 -value of the reference item at 1.41 mg/L after 24 h was within the prescribed concentration range of 1.0 to 2.5 mg/L according to AQS, DIN Guideline 38412 L 30. Water quality parameters of pH-value and dissolved oxygen concentration measured at 0 and 48 h were determined to be within the acceptable limits. The validity criteria of the test guideline were fulfilled. The EC50 value and EC10 value were determined to be above 100 mg/L after 48 h (reference 6.1.3-1).