Sodium 5-oxo-DL-prolinate

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

24 July 2001 to 26 July 2001

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: A non GLP study performed to standardised guidelines on a read-across substance with a sufficient level of detail to assess the quality of the submitted data.

Reason / purpose for cross-reference:

other: Target substance

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Deviations:

no

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: A stock solution was prepared at 100 mg/L in dilution water, mixed by agitation.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Age at study initiation: 2 to 24 hours old
Culture conditions: In 2-3 L glass vessels with approximately 1.8 L culture medium, by 21 °C (temperatures of 20-25 °C were tolerated), in an incubator, 16 h illumination, illumination strength max 20 µmol·m^-2·s^-1.
- Food type: A mix of Scenedesmus subspicatus and Chlorella vulgaris, with an algae cell density of > 10^6 cells/mL.
- Amount: ad libitum
- Frequency: 5 x weekly

ACCLIMATION
- Acclimation period: 2 hours in dilution water.

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Hardness:

Hardness as CaCO3 256 mg/L

Test temperature:

18 - 22 ± 1°C

pH:

ranged from 7.57 to 7.75

Dissolved oxygen:

8.10 mg/L

Nominal and measured concentrations:

Nominal concentration: 100 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: Glass beakers (5 cm x 8 cm).
- Fill volume: 50 mL.
- Volume of medium used: 20 mL
- No. of organisms per vessel: 5 for test material exposure vessels and 10 for reference substance vessels
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 2
- Reference substance concentrations: 0.58, 1.0, 1.8, 3.2, 5.8 mg/L.

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Dilution water according to EU Method C.2 (Acute Toxicity for Daphnia).
- Conductivity: 670 µS/cm
- Culture medium: M4 Elendt
- Intervals of water quality measurement: pH, dissolved oxygen concentration, temperature, conductivity and total hardness were measured prior to study initiation. DOC was determined in fresh media at 0 h and at 48 hours in old media. At the beginning of the test the water parameters (pH-value, dissolved oxygen concentration) were measured in one additional replicate per concentration and control. After 48 h the same water parameters were measured in all replicates per concentration and control.

OTHER TEST CONDITIONS
- Photoperiod: 16/8 hour light/dark.
- Light intensity: Diffuse light, maximum strength 20 µmol.m^-2.s^-1

EFFECT PARAMETERS MEASURED: The percentage immobility was determined in all test and control groups after 24 h and 48 h.

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

- Any observations that might cause a difference between measured and nominal values: The test material was clearly dissolved throughout exposure.
- Water parameters at 48 hours: pH ranged from 7.57 to 7.69, oxygen concentration ranged from 8.02 to 8.14 mg/L.

Results with reference substance (positive control):

- The EC50 result with the reference substance was within he prescribed concentration range of 1.0 - 2.5 mg/L.
- EC50: 2.0 (1.8 to 2.2).
- Other: EC10 1.3 and EC100 5.8.

Table 1: Percentage Number of Daphnids Immobilised after 24 and 48 hours of Exposure

Nominal Concentration (mg/L)	Replicates at 24 hours					Replicates at 48 hours
	1	2	3	4	Mean	1	2	3	4	Mean
100	0	0	0	0	0	0	0	0	0	0
Control	0	0	0	0	0	0	0	0	0	0

Validity criteria fulfilled:

yes

Conclusions:

Under the conditions of the study, no biologically significant effects were observed in daphnids exposed to the test material at 100 mg/L for 48 hours.

Executive summary:

The acute toxicity of the test material to aquatic invertebrates was determined in a 48 hour immobilisation test using Daphnia magna. Daphnids were exposed to the test material in a limit test at 100 mg/L, performed according to the standardised guidelines OECD 202 and EU Method C. 2. Under the conditions of the study, no biologically significant effects were observed in treated daphnids and the EC50 was estimated to be greater than 100 mg/L.

This study was conducted on the the read across substance sodium 5-oxo-L-prolinate.

Reference 2

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

12 July 2016 to 07 September 2016

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:

no

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Deviations:

no

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: JMAFF 2-7-2-1 The guidelines related to the study reports for the registration application of pesticide

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source: Provided by sponsor
- Lot/batch No.of test material: 160224
- Expiration date of the lot/batch: 24 February 2019

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: Controlled room temperature (15-25 °C, below 70 RH%), protected from light

Analytical monitoring:

yes

Details on sampling:

- Concentrations: Analytical measurements were performed on samples of 100 mg/L nominal concentrations taken at the beginning and at the end of the experiment.
- Sampling method: HPLC
- Sample storage conditions before analysis: Controlled room temperature (15-25 ˚C, below 70 RH%), protected from light.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
A stock solution with a concentration of 100 mg/L (nominal) was prepared with test material and test medium (ISO Medium). As a limit test was carried out, further dilution of stock solution was not performed.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Age at study initiation: They were less than 24 hours old at the beginning of the test.
- Feeding during test: The animals were not fed during the test.

ACCLIMATION
- Acclimation period: There was no acclimatization because the water used was similar to the culture water. The same composition of reconstituted water was used for the tests and for breeding the test animals.


METHOD FOR PREPARATION AND COLLECTION OF EARLY INSTARS OR OTHER LIFE STAGES:
- Breeding: The Daphnia are bred in Ecotoxicological Laboratory of CiToxLAB Hungary Ltd. The health of the stock animals is continuously monitored by visual daily checking. Abnormal behaviour or significant decrease of population is recorded.

Test type:

static

Water media type:

other: Reconstituted water (ISO medium)

Limit test:

yes

Total exposure duration:

48 h

Hardness:

246 mg/L (as CaCO3)

Test temperature:

20.2 – 20.4 °C

pH:

7.48 – 7.83

Dissolved oxygen:

8.5 – 8.9 mg/L

Salinity:

No data

Conductivity:

No data

Nominal and measured concentrations:

Nominal: 100 mg/L
Measured: 103 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: Glass beaker
- Type (delete if not applicable): No data
- Material, size, headspace, fill volume: At least 5 mL test solution/animal
- No. of organisms per vessel: 5 organisms per vessel
- No. of vessels per concentration (replicates): Four
- No. of vessels per control (replicates): Four

TEST MATERIAL/SAMPLE PREPARATION
- A stock solution with a concentration of 100 mg/L (nominal) was prepared with direct addition of the test item, mixed into the test medium (ISO Medium) using ultrasonic bath for 5 minutes. As a limit test was carried out, further dilution of stock solution was not performed.

OTHER TEST CONDITIONS
- Adjustment of pH: No adjustment
- Photoperiod: The test was carried out in 16-hour light and 8-hour dark cycle.


VEHICLE CONTROL PERFORMED: Yes

RANGE-FINDING STUDY
- Test concentrations: 0.1, 1.0, 10, 100 mg/L
- Results used to determine the conditions for the definitive study: Yes. Because toxic response was not observed during the preliminary concentration rangefinding test, a Limit Test was carried out using only one test concentration (100 mg/L) and one control group in a static system. As the measured concentrations deviated by not more than 20 % from the nominal, the biological results are based on the nominal concentration.

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Key result

Duration:

24 h

Dose descriptor:

EC50

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

Key result

Duration:

48 h

Dose descriptor:

EC100

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

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:

The number of immobilised animals and the percentage of immobility were determined after 24 and 48 hours. No immobility was observed either in the treatment or control vessels. In addition to immobility, no abnormal behaviour or appearance of test animals was reported.

VALIDITY CRITERIA
All validity criteria were met during this study. in the control, including the control containing the solubilising agent, not more than 10 per cent of the Daphnia were immobilised or trapped at the surface of the water and the dissolved oxygen concentration at the end of the test in control and test vessels should be ≥ 3 mg/L of the air saturation value at the temperature used.

Results with reference substance (positive control):

- Results with reference substance valid: Yes; for the evaluation of the quality of the Daphnia clone and the experimental conditions, Potassium dichromate is tested at least twice a year to demonstrate satisfactory test conditions.
- EC50/LC50: The 24 h EC50 was 1.16 mg/L (95 % confidence limits 1.07 to 1.25 mg/L)

Reported statistics and error estimates:

No statistical analysis was performed because of the lack of toxic effects. The EC50, NOEC, LOEC and EC100 values were determined directly from the raw data.

Validity criteria fulfilled:

yes

Conclusions:

Under the conditions of this Daphnia magna acute immobilisation study, the 24 h and 48 h EC50 value was > 100 mg/L (nominal), the 48 h EC100 value was > 100 mg/L (nominal), the 48 h No-Observed Effect Concentration (NOEC) was 100 mg/L (nominal) and lastly the 48 h Lowest Observed Effect Concentration (LOEC) was > 100 mg/L (nominal). The values obtained were based on the nominal concentration of the test material.

Executive summary:

The acute toxicity of the test material to Daphnia magna was investigated in a study conducted in accordance with the standardised guidelines OECD 202, EU Method C.2, the US EPA OPPTS 850.1010, guidelines for studies on the new chemical substance as required by the Chemical Substance Control Law (Japan) and JMAFF 2-7-2-1 under GLP conditions.

Acute toxicity of the test material on Daphnia magna was assessed in an acute immobilisation test, over an exposure period of 48 hours in a static test. Because no toxic response was observed during the preliminary range-finding test, a Limit Test was carried out using only one test concentration (100 mg/L) and one control group in the definitive test. The test concentration was analytically determined at the start and at the end of the experiment. Measured concentration was 103.2 mg/L at the start and 102.9 mg/L at the end of the test. As the measured concentrations deviated not more than 20 per cent from the nominal in all cases, biological results are based on the nominal concentration. Twenty animals, divided into four groups (glass beakers) of five animals each were used at the test concentration and for the control. All validity criteria were met during this study.

Under the conditions of this Daphnia magna acute immobilisation study, the 24h and 48h EC50 value was > 100 mg/L (nominal), the 48h EC100 value was > 100 mg/L (nominal), the 48h No-Observed Effect Concentration (NOEC) was 100 mg/L (nominal) and lastly the 48h Lowest Observed Effect Concentration (LOEC) was > 100 mg/L (nominal). The values obtained were based on the nominal concentration of the test material.

Description of key information

An experimental study and a Read-Across study were used to asses the short term toxicty of a test material to Aquatic Invertebrates.

No biologically significant effects were observed in daphnids exposed to the test material at 100 mg/L for 48 hours. The EC50 was greater than 100 mg/L.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

100 mg/L

Additional information

The acute toxicity of the test material to Daphnia magna was investigated in a study conducted in accordance with the standardised guidelines OECD 202, EU Method C.2, the US EPA OPPTS 850.1010, guidelines for studies on the new chemical substance as required by the Chemical Substance Control Law (Japan) and JMAFF 2-7-2-1 under GLP conditions. The study was assigned a reliability score of 2 in line with the principles for assessing data quality as defined by Klimisch (1997).

Acute toxicity of the test material on Daphnia magna was assessed in an acute immobilisation test, over an exposure period of 48 hours in a static test. Because no toxic response was observed during the preliminary range-finding test, a Limit Test was carried out using only one test concentration (100 mg/L) and one control group in the definitive test. The test concentration was analytically determined at the start and at the end of the experiment. Measured concentration was 103.2 mg/L at the start and 102.9 mg/L at the end of the test. As the measured concentrations deviated not more than 20 per cent from the nominal in all cases, biological results are based on the nominal concentration. Twenty animals, divided into four groups (glass beaker) of five animals each were used at the test concentration and for the control. All validity criteria were met during this study.

Under the conditions of this Daphnia magna acute immobilisation study, the 24h and 48h EC50 value was > 100 mg/L (nominal), the 48h EC100 value was > 100 mg/L (nominal), the 48h No-Observed Effect Concentration (NOEC) was 100 mg/L (nominal) and lastly the 48h Lowest Observed Effect Concentration (LOEC) was > 100 mg/L (nominal). The values obtained were based on the nominal concentration of the test material.

The supporting study (Noack 2001) is a non-GLP study performed in accordance with standardised guidelines. The study was assigned a reliability score of 2 in line with the principles for assessing data quality as defined by Klimisch (1997). Under the conditions of the study, no biologically significant effects were observed in daphnids exposed to the test material at 100 mg/L for 48 hours. The EC50 can therefore be estimated to be greater than 100 mg/L.