Yucca schidigera, ext.

Short-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2019-01-29 - 2019-01-31 (experimental phase)

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

under GLP

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2019

Report date:

2019

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Version / remarks:

OECD Guideline for Testing of Chemicals No. 202, adopted 13. Apr. 2004: ”Daphnia sp., Acute Immobilisation Test“

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Version / remarks:

Commission Regulation (EC) No. 440/2008, Method C.2. “Daphnia sp. Acute Immo-bilisation Test”, adopted 30. May 2008

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

Landesamt für Umwelt, Kaiser-Friedrich-Straße 7, 55116 Mainz, Germany

Test material

Test material information

Constituent 1

Reference substance name:

Yucca schidigera, ext.

EC Number:

607-033-5

Cas Number:

223749-05-1

IUPAC Name:

Yucca schidigera, ext.

Test material form:

solid: particulate/powder

Remarks:

fine beige

Details on test material:

Storage: Room Temperature (20 ± 5 °C)
Homogeneity: homogeneous

Specific details on test material used for the study:

The test item was stored in the test facility in a closed vessel at room temperature (20 ± 5°C)

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

- Concentrations: 0, 100 mg/L

Test solutions

Vehicle:

no

Remarks:

dilution water

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: A solution containing 100.5 mg/L in dilution water was prepared.
- Evidence of undissolved material (e.g. precipitate, surface film, etc.): none

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: water flea
- Strain/clone: Daphnia magna STRAUS Berlin
- Age at study initiation (mean and range, SD): between 0 and 24 hours
- Method of breeding: Daphnia magna is bred in the laboratory throughout the year. The animals are kept for the use in toxicity tests. They multiply by parthenogenesis, thus being genetically identical. The keeping is performed similar to the method described in the OECD guideline.
Vessels: preserving glasses, nominal volume 2 L
Medium: M4-Medium (recipe of ELENDT)
Food: green algae (Desmodesmus subspicatus)
Medium renewal: twice a week
Photo period: 16/8 hours, using neon tubes
Temperature: 20 ± 2 °C
- Source: Umweltbundesamt Berlin
- Feeding during test
none

METHOD FOR PREPARATION AND COLLECTION OF EARLY INSTARS OR OTHER LIFE STAGES, INCLUDING CULTURING CONDITIONS:
Selection of Daphnia
18 hours and 55 minutes before the start of the test, the adult animals were separated from the young. 40 minutes before test start, the adults were caught with the help of a glass tube, and the newborn daphnia (age < 24h) were sieved from the medium and im-mediately placed into a beaker containing dilution water. After the settling-in period, ani-mals which showed no apparent damage were used for the test.
Switching from M4-medium (husbandry) to Dilution water (test) has been shown not to cause any detrimental effects for test daphnia.

Study design

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Post exposure observation period:

none

Test conditions

Hardness:

2.502 mmol/L
250 mg CaCO3/L

Test temperature:

20.4 – 21.3 °C

pH:

7.7 - 7.9

Dissolved oxygen:

8.2 - 8.8 mg/L

Nominal and measured concentrations:

Nominal: 0, 100 mg/L
Measured (t = 0h): 0, 96.2 mg/L
Measured (t = 48h): 0, 103.1 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: beakers
- Type (delete if not applicable): open
- Material, size, headspace, fill volume: glass beakers, nominal volume 50 mL, tall shape, 20 ± 5 mL fill volume
- Volume of solution: 20 ± 5 mL
- Aeration: After preparation, the dilution water was aerated.
- Renewal rate of test solution (frequency/flow rate): none
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4
- No. of vessels per vehicle control (replicates): n/a

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16/8 hours, using neon tubes

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
Immobility: after 24 and 48 hours
Test item concentration, pH, O2: after 0 and 48 hours

VEHICLE CONTROL PERFORMED: not required

Reference substance (positive control):

yes

Remarks:

Potassium dichromate K2Cr2O7 (CAS No. 7778-50-9) was used as positive control in a current reference study.

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Effect concentrations 2

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

Effect concentrations 3

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Effect concentrations 4

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: none stated
- Immobilisation of control: none
- Abnormal responses:
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: none
- Effect concentrations exceeding solubility of substance in test medium: none

Results with reference substance (positive control):

- Results with reference substance valid? yes
- Relevant effect levels: 24h EC50
- Limit test: no
- Dose-response test: yes
- ECx: The 24h-EC50 value was determined as 2.05 mg/L. The value was within the requested range for the 24h-EC50 between 0.6 - 2.1 mg/L of potassium dichromate K2Cr2O7 as specified in the OECD guideline.

Reported statistics and error estimates:

As no significant immobilisation occurred, no statistical evaluation was performed.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The study was conducted under GLP according to OECD guideline 202 and EU method C.2 on the registered substance itself. The method is to be considered scientifically reasonable with no deficiencies in documentation or deviations from the guidelines, the validity criteria were met. Hence, the results can be considered as reliable to assess the toxicity of the test item resp. the registered substance towards daphnids.
The study was performed as a limit test at 100 mg/L. For the test concentration and the blank control, 20 Daphnia were exposed to the test item for 48 hours in a static test system. After 24 and 48 hours, the immobilised Daphnia were counted.
One of the animals was immobilised in the treatment. None of the animals was immobilised in the blank control. As no significant immobilisation occurs, no statistical evaluation was performed.
Potassium dichromate K2Cr2O7 (CAS No. 7778-50-9) was used as positive control in a current reference study to assure that the test conditions are reliable.
At the start and at the end of the test, the content of the test item in the test solutions was determined using measurement of total organic carbon (TOC). The measured concentration based on TOC measurement was 96 % of the nominal concentration at the beginning of the test and 103 % of the nominal concentration at the end of the test. Therefore, the determination of the results was based on the nominal concentrations.
The 48h EC50 was determined to be >100 mg/L..
Based on the obtained results, the registered substance does not need to be classified as toxic to the environment, neither acutely nor chronic, according to the Regulation (EC) No. 1272/2008.

Executive summary:

The study was conducted under GLP according to OECD guideline 202 and EU method C.2 on the registered substance itself. One valid experiment was performed.

One valid experiment was performed.

The study was performed as a limit test at 100 mg/L. For the test concentration and the blank control, 20 Daphnia were exposed to the test item for 48 hours in a static test system. After 24 and 48 hours, the immobilised Daphnia were counted.

One of the animals was immobilised in the treatment. None of the animals was immobilised in the blank control. As no significant immobilisation occurred, no statistical evaluation was performed.

Potassium dichromate K2Cr2O7 (CAS No. 7778-50-9) was used as positive control in a current reference study to assure that the test conditions are reliable.

At the start and at the end of the test, the content of the test item in the test solutions was determined using measurement of total organic carbon (TOC). The measured concentration based on TOC measurement was 96 % of the nominal concentration at the beginning of the test and 103 % of the nominal concentration at the end of the test. Therefore, the determination of the results was based on the nominal concentrations.

The following results were determined for the test item Yucca schidigera, ext. (species: Daphnia magna).

48h-NOEC ≥ 100 mg/L (nominal)
48h-LOEC > 100 mg/L (nominal)
24h-EC50 > 100 mg/L (nominal)
48h-EC50 > 100 mg/L (nominal)

The test item does not need to be classified as toxic to the environment, neither acutely nor chronic, according to the Regulation (EC) No. 1272/2008.