Phosphoric acid, C14-15-branched and linear alkyl esters, potassium salts

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

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:

equivalent or similar to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

Name: Phosphoric acid, C14-15 branched and linear alkyl esters, potassium salts
CAS No.: 1893414-79-3
Physical state: white solid at 20 °C
Batch No.: PU61810016
Re-certification date of batch: 09 March 2018
Purity: 100 % (UVCB, lyophilized solid, water content 0.85 % (w/w))
Stability: stable under test conditions
Storage condition of test material: Room temperature, protected from light

Analytical monitoring:

yes

Details on sampling:

Analytical samples were taken from all test item concentrations 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. 500 µL samples were taken and stabilized with 500 µL methanol.

Vehicle:

no

Details on test solutions:

Based on the results of a non GLP range-finding test, the following nominal concentrations were tested in the main test: 1.00, 2.20, 4.84, 10.6 and 23.4 mg/L and control. 24 hours before test start the glass vessels were saturated with respective test item concentration. The necessary amount of test item for preparing the stock solution S1 was weighed on a weighing scoop and transferred to a volumetric flask. Test medium was added up to the bench mark and the solution was homogenised by shaking and treated with 5 minutes of sonication. Afterwards the solution was turbid and small white flakes were evenly spread. Lower test solutions were prepared by dilution of the appropriate stock solutions with test medium. The dilutions were clear and transparent. The preparation procedure was repeated after 24 hours. Approximately 50 mL of the prepared solutions were transferred to each test vessel.

Nominal concentration Test item solution Dilution solution Final volume Volume per test vessel Solution
[mg/L] [mg] No. [mL] [mL] [mL] No.
23.4 23.4 - - 1000 ~50 S1
10.6 - S1 455 1000 ~50 V1
4.84 - V1 455 1000 ~50 V2
2.20 - V2 455 1000 ~50 V3
1.00 - V3 455 1000 ~50 V4
0 - - - - ~50 Control

Test organisms (species):

Daphnia magna

Details on test organisms:

Daphnia magna Straus, Clone V, was used as the test organism. The animals are continuously bred in the laboratory and were originally purchased in a healthy condition from the Federal Environment Agency in Berlin/Germany. Daphnia magna was bred as single culture (1 daphnid per 100 mL) in Elendt M4 medium. The pH-value of the aerated water was within a range of 6.0 – 9.0. The dissolved oxygen was above 60 % saturation and the total hardness 140 - 250 mg/L (as CaCO3), corresponding to 7.8 - 14°dH. The animals were fed with single cell green algae (Desmodesmus subspicatus, formerly Scenedesmus subspicatus) at least three times a week. The daphnids were reared at a temperature of 20 ± 2 °C in a climatic chamber with 16 hours of illumination and 8 hours of darkness. The medium was changed three times per week. A pipette was used to separate the young daphnids from the adults. Freshly hatched daphnids less than 24 hours old were used for the test

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

Elendt M4 medium was used as test medium. At test initiation the total hardness was 12°dH (214 mg/L as CaCO3).

Test temperature:

Temperature: 19.0 – 20.6 °C

pH:

Elendt M4 medium was used as test medium. At test initiation the pH-value of the control (untreated test medium) was 7.83.

Dissolved oxygen:

Elendt M4 medium was used as test medium. At test initiation the dissolved oxygen concentration was 9.4 mg/L.

Salinity:

Elendt M4 medium was used as test medium.

Conductivity:

Elendt M4 medium was used as test medium.

Details on test conditions:

Test Conditions
Test procedure: Semi-static
Duration: 48 hours
Temperature: 19.0 – 20.6 °C
Oxygen concentration: ≥ 8.8 mg/L
pH-value: 7.77 – 8.08
Exposure to light: 16 hours photoperiod /8 hours darkness daily
Feeding: None
Test vessels: Four 100 mL glass beakers per concentration, each filled with ~50 mL, one additional replicate for pysicochemical
measurements without test organisms
Loading: ~10 mL of test solution for each animal
Aeration: None
Number of animals: 20 per concentration in 4 replicates of 5

Reference substance (positive control):

yes

Remarks:

potassium dichromate

Key result

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

7.96 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat. (dissolved fraction)

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

23.4 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat. (total fraction)

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 7.96 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat. (dissolved fraction)

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 23.4 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat. (total fraction)

Basis for effect:

mobility

Details on results:

Control immobilisation: The percentage of immobilisation should be ≤ 10 %. In this study the control immobilisation was 0 %.
Oxygen concentration: The dissolved oxygen concentration at the end of the test should be ≥ 3 mg/L in all test units. In this test, the dissolved oxygen concentration at the end of the test was ≥ 8.8 mg/L.

Results with reference substance (positive control):

Toxic Reference

In order to check the validity of the results, the toxicity of the reference item potassium dichromate was tested at 1.0 and 2.0 mg/L with 20 test organisms per test concentration. The results indicate an EC50 (24 h) of the reference item potassium dichromate between 1.0 and 2.00 mg/L. Since the results are in accordance with the requirements of the OECD guideline 202 and fall within the historical data generated with the reference item at the testing facility, the daphnids were suitable for the determination of the toxicological effects of the test item.

Reported statistics and error estimates:

The values for EC50 could not be determined since the immobilisation was below 50 % in the test. The NOEC was established based on the highest concentration at which the immobilisation is not higher than the allowed control immobilisation (≤ 10 % immobilisation).

Validity criteria fulfilled:

yes

Conclusions:

According to the results of the test, the EC50 (48 h) of the test item for immobilisation was supposed to be > 23.4 mg/L (nominal) respectively > 7.96 mg/L (actual). The corresponding NOEC (48 h) was 23.4 mg/L (nominal) respectively 7.96 mg/L (actual).

Executive summary:

In the Klimisch 1 GLP study the acute toxicity of the test item to daphnia was determined in a 48‑hour semi static test according to Part C.2 of the Commission Regulation (EC) No 440/2008 and the OECD Guideline for Testing of Chemicals No. 202 (2004). According to the results of the test, the EC50 (48 h) of the test item for immobilisation was supposed to be > 23.4 mg/L (nominal) respectively > 7.96 mg/L (actual). The corresponding NOEC (48 h) was 23.4 mg/L (nominal) respectively 7.96 mg/L (actual).

Description of key information

According to the results of the test, the EC50 (48 h) of the test item for immobilisation was supposed to be > 23.4 mg/L (nominal) respectively > 7.96 mg/L (actual). The corresponding NOEC (48 h) was 23.4 mg/L (nominal) respectively 7.96 mg/L (actual).