Butanedioic acid, 2,3-dihydroxy- [R-(R*,R*)]-,C12-13-branched alkyl esters

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:

2017-04-24 to 2017-05-23

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:

no remarks

Deviations:

no

Principles of method if other than guideline:

none

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

none

Analytical monitoring:

yes

Details on sampling:

- Concentrations: 0; 4.27; 9.39; 20.7; 45.5; 100 mg/L nominal
- Sampling method: Analytical data are required by the guidelines for verification of test item loading rates as well as the stability of the test item over the entire test period. Analytical samples were taken from all test item loading rates and control at test start and after 24 hours from fresh and aged solutions and after 48 hours from aged solutions. For each sampling also a retain sample was taken.
- Sample storage conditions before analysis: All samples were stored deep frozen until they were transferred to the analytical laboratory.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
Based on the results of a non GLP range-finding test, the following nominal test item loading rates were tested in the main test: 4.27, 9.39, 20.7, 45.5 and 100 mg/L and control. 24 hours before test start the glass vessels were saturated with respective test item concentration.
All solutions were prepared by directly weighing the necessary amount of test item in 1000 mL test medium. These solutions were stirred for 48 h (at room temperature in the dark) and let settle down for 1 h (based on OECD Series on Testing and Assessment No. 23). In these solutions, oil droplets were observed at the surface of the solutions. After the settling the necessary volumes for the test were withdrawn via a Teflon tube from the medium level of each solution. The preparation procedure was repeated after 24 hours. About 50 mL of the prepared solutions were transferred to each test vessel.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna Straus, Clone V.
- Source: In-house culture.
- Age at study initiation (range): freshly hatched < 24 hours.
- Feeding during test: No.


ACCLIMATION
- Acclimation period: not mentioned
- Acclimation conditions (same as test or not): not mentioned.
- Type and amount of food: single cell green algae (Desmodesmus subspicatus, formerly Scenedesmus subspicatus).
- Feeding frequency: The animals were fed with at least three times a week.
- Health during acclimation (any mortality observed): No.

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Post exposure observation period:

Not applicable.

Hardness:

232 mg CaCO3/L

Test temperature:

19.8-21.3 °C

pH:

7.45-8.11

Dissolved oxygen:

>=7.5 mg/L

Salinity:

Not applicable.

Nominal and measured concentrations:

Nominal: 4.27; 9.39; 20.7; 45.5; 100 mg/L
nominal: 4.27 mg/L: measured: 0h: 0.0903 mg/L; 24 h fresh: 0.244 mg/L; 48 h aged: 0.0246 mg/L
nominal: 9.39 mg/L: measured: 0h: 0.152 mg/L; 24 h fresh: 0.299 mg/L; 48 h aged: 0.104 mg/L
nominal 20.7 mg/L: measured: 0h: 0.183 mg/L; 24 h fresh: 0.236 mg/L; 48 h aged: 0.0248 mg/L
nominal 45.5 mg/L: measured: 0h: 0.523 mg/L; 24 h fresh: 0.528 mg/L; 48 h aged: 0.158 mg/L
nominal 100 mg/L: measured: 0h: 1.44 mg/L; 24 h fresh: 0.338 mg/L; 48 h aged: 0.078 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: Glass vessel, 100 mL capacity, covered with a glass plate (thus reducing evaporation)
- Fill volume: 50 ml in each replicate
- Aeration: None.
- No. of organisms per vessel: 20 per loading rate in 4 replicates of 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4

TEST MEDIUM / WATER PARAMETERS
- Dilution water: not mentioned
- Intervals of water quality measurement: not mentioned

OTHER TEST CONDITIONS
- Adjustment of pH: No.
- Photoperiod: 16/8 h light/dark cycle.
- Light intensity: not mentioned

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
Immobility after 24h and 48h of exposure.

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 2.2
- Justification for using less concentrations than requested by guideline: Range finding study.

Range-finding study
A non-GLP range-finding test was performed with the following test item loading rates: Control, 100, 10.0 and 1.00 mg/L.
After 24 hours of exposure no immobilisation was in the control and the highest test item loading rate of 100 mg/L. No immobilisation higher than the allowed control immobilisation was observed at the test item loading rate of 1.00 mg/L. 15 % of the daphnids were immobile at 10.0 mg/L.

After 48 hours of exposure no immobilisation was observed in the control. 30 % immobilisation was observed at 1.00 mg/L and 40 % at 10.0 mg/L. In the highest test item loading rate of 100 mg/L 50 % of the daphnids were immobile.
After 24 hours in the test item loading rates of 10.0 and 100 mg/L the daphnids did partly swim at the water surface.
After 48 hours the same observations were made as after 24 h. Additionally in the test item loading rate of 100 mg/L white faces were observed at the water surface.

Reference substance (positive control):

yes

Remarks:

Potassium dichromate (historic (monthly data) of test institute)

Key result

Duration:

48 h

Dose descriptor:

EL50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

other: loading rate (Water Accommodated Fraction )

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

NOELR

Effect conc.:

20.7 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

loading rate (water accomodated fraction)

Basis for effect:

mobility

Details on results:

- Behavioural abnormalities: None reported.
- Observations on body length and weight: None reported.
- Other biological observations: None reported.
- Mortality of control: 5 % after 48 h
- Other adverse effects control: None reported.
- Abnormal responses: None reported.
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: No.
- Effect concentrations exceeding solubility of substance in test medium: Not applicable (WAF was tested).

Results with reference substance (positive control):

Historic (monthly) reference data of test institute for potassium dichromate:
EC50 (24 h) 1 mg/L according to OECD 202 and fall within the historical data generated with the reference item at the testing facility

Validity criteria fulfilled:

yes

Conclusions:

According to the results of the test, the EL50 (48 h) for immobilisation was supposed to be > 100 mg/L (nominal). The corresponding NOELR (48 h) was 20.7 mg/L (nominal).

Executive summary:

An acute immobilisation test with Daphnia magna (STRAUS) was conducted with the test item according to OECD 202. According to the results of the test, the EL50 (48 h) for immobilisation was supposed to be > 100 mg/L (nominal). The corresponding NOELR (48 h) was 20.7 mg/L (nominal).

Description of key information

An acute immobilisation test with Daphnia magna (STRAUS) was conducted with the test item according to OECD 202. According to the results of the test, the EL50 (48 h) for immobilisation was supposed to be > 100 mg/L (nominal). The corresponding NOELR (48 h) was 20.7 mg/L (nominal).

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

100 mg/L